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HUMAN CHARACTERISTICS and HANDLING STRATEGIES:
THE EFFECTS ON THE BEHAVIORAL AND PHYSIOLOGICAL
RESPONSE OF PIGS TO STUDENT HANDLERS

presented by

Madonna Eva Gemus I

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HUMAN CHARACTERISTICS and HANDLING STRATEGIES:
THE EFFECTS ON THE BEHAVIORAL AND PHYSIOLOGICAL
RESPONSE OF PIGS TO STUDENT HANDLERS
By

Madonna Eva Gemus

A THESIS
Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

MASTER OF SCIENCE

Department of Large Animal Clinical Sciences

1998

ABSTRACT
HUMAN CHARACTERISTICS and HANDLING STRATEGIES:
THE EFFECTS ON THE BEHAVIORAL AND PHYSIOLOGICAL
RESPONSE OF PIGS TO STUDENT HANDLERS.
By

Madonna Eva Gemus

Unpleasant handling of pigs can adversely affect the animal’s physiological and
behavioral response. The purpose of this study was to evaluate human characteristics that
improve pig handling. University students completed a survey assessing interpersonal
skills and were matched based on esteem score, gender and experience. Students (n=32),
moved pigs through a circuit with typical on-farm obstacles. Human and pig behavior
data, and time in the circuit was obtained from video recordings and observers. Salivary
cortisol, monitored in pigs and handlers, was measured by radioimmunoassay. Linear
regression analyses, was used for dependent variables time and cortisol. Human behavior
“problemsolv” was associated with less time (P3001), while “slapping” and
“problemsolv” were associated with a higher human salivary cortisol (P5005). Pig
response “escape” tended to increase time (P5001) and was strongly correlated with
“turn” (r=0.78). Time in the circuit and a stress indicator were affected by the qualitative

nature of the human-pig interaction.

It gives me great pleasure to dedicate this work
to Scott Benjamin,
and to my father and my mother,
Gerald and Madonna Gemus,
for their unfailing love, support, and encouragement.

iii

ACKNOWLEGMENTS

I would like to extend my thanks and gratitude to graduate committee members, Drs.
Adroaldo J. Zanella, Raymond F. Nachreiner, Joel Aronoff and Frederik J. Derksen, for
their guidance and assistance. I would especially like to extend my sincere and heartfelt
gratitude to Dr. Adroaldo J. Zanella, my mentor and major professor, for his guidance,
friendship, and assistance above and beyond the work entailed within this project.

I would also like to thank those in the Behavior Lab, the Swine Barn, and the PALE
pavilion within the Department of Animal Science, especially Telmo Oleas, Amy Martin,
Mandy Gendron, Scott Benjamin, and Elisette Rivera, Al Snedegar, Marshall Williams,
and Gerri McCully.

In addition, Dr. Paul Bartlett was invaluable in his support and advice on statistical
analysis, as were Dr. Susan Ewart, Dr. Loic Dejardin and Ms. Angela Corley for their
advice in completing the Master of Science program and the manuscript.

Finally, I would like to thank Dr. Frederik Derksen for his confidence in the process
of academic freedom and his encouragement during this project encompassing both
human and animal ethology.

Partial funding for this project was provided by a grant through the Animal Health

Diagnostic Lab.

iv

TABLE OF CONTENTS

LIST OF TABLES ................................................................................. vii
LIST OF FIGURES ................................................................................. ix
INTRODUCTION .................................................................................... 1
CHAPTER 1
LITERATURE REVIEW ........................................................................... 4
Handler Characteristics ........................................................................ 4
The Foundation of Personality ........................................................... 4
Personality and the Stoclqoerson ......................................................... 5
Developing Personality and Behavior ................................................... 7
Self-esteem .................................................................................. 8
Human Behavior ................................................................................. 9
Problem Solving Behavior: The Human Endowment ................................ 10
Measuring Personality, Self-Esteem and Problem-Solving Behavior ............. 12
Behavior of the Stockperson ............................................................ 13
Pig Behavior in Response to the Handler ................................................... 15
Handling of Pigs .......................................................................... 19
Spatial Memory in Pigs .................................................................. 20
Handler to Pig Vocal Interaction ...................................................... 21
Handler Posture .......................................................................... 21
Stress Response in Humans and Pigs ....................................................... 21
Physiological Response to Stress ...................................................... 22
Physiological Indicators of Stress ...................................................... 24
Behavioral Response to Stress in Animals ............................................ 26
Environmental Enrichment .............................................................. 28
Human-Pig Interaction ....................................................................... 28
Quantity and quality of handling ....................................................... 30
Summary ....................................................................................... 32
HYPOTHESIS ................................................................................. 35
MATERIALS and METHODS ............................................................. 36
Study Population ........................................................................ 36
Circuit Design ............................................................................ 38

Animals .................................................................................... 44

Experimental Protocol .................................................................. 44
Behavior ................................................................................... 46

Human Behavior ................................................................... 46

Pig Behavior ........................................................................ 49

Cortisol Analysis ........................................................................ 51
Validation Studies ........................................................................ 53
Statistical Analyses ...................................................................... 59
Definition: All Pigs and Focus Pig ............................................... 59
Dependent variable analysis ...................................................... 60
Independent variable analysis ..................................................... 62
RESULTS ....................................................................................... 64
Study Population .......................................................................... 64
DescriptiveResultsM ..64

AND VA of Handler Charactenstzcs .............................................. 65

Human Salivary Cortisol ................................................................ 67

Pig Salivary Cortisol ..................................................................... 68
Descriptive Analysis ................................................................ 68
Time in the Circuit ........................................................................ 69
Handler Behavior ......................................................................... 71
Correlation Amoung Human Behaviors .......................................... 71
Eflects of Handler Behavior on Human Salivary Cortisol ..................... 73

The Eflect of Human Behavior on Pig Salivary Cortisol ...................... 73
The Efl'ect Human Behavior on Time in the Circuit ............................ 74

Pig Behavior ............................................................................... 75
Correlation among Pig Behaviors ................................................ 76
Regression Analysis of Pig Behavior .................................................. 76

Pig Salivary Cortisol ................................................................ 78
Time in the Circuit ................................................................... 78
DISCUSSION .................................................................................. 80
The Study Population .................................................................... 80
Self-esteem ............................................................................ 80

Gender ................................................................................ 82

Human Cortisol ...................................................................... 82
Handler Strategies ........................................................................ 84
Human Behavior and Pig Biological Response ................................. 84

Pigs Behavioral Response .......................................................... 86
Selection of Stockpeople ................................................................ 88
CONCLUSION ................................................................................ 90
APPENDIX .................................................................................... 92
LIST OF REFERENCES ...................................................................... 97

vi

LIST OF TABLES

TABLE 1. Human behaviors categorized and defined ......................................... 48
TABLE 2. Pig behaviors categorized and defined .............................................. 50
TABLE 3. Measures of cortisol retention using cotton rolls, cotton buds and

control samples from tube 1 (T1) and tube 2 (T2) ............................................. 54
TABLE 4: Basal salivary cortisol (nmol/l) determined from 5 different pigs and three
samples collected within a two minutes time period ........................................... 57
TABLE 5. Descriptive statistics of variables of human behavior ............................ 65

TABLE 6. AN OVA computation of self esteem and rate of human behavior
of the All Pigs data and the data set restricted to Focus Pig .................................... 66

TABLE 7. AN OVA computation of gender and rate of human behavior
of the All Pigs data and the data set restricted to Focus Pig Only ............................ 67

TABLE 8. AN OVA computation of mean human cortisol (nmol/l) levels and
categorical variables using All Pig data and Focus Pig only data set ........................ 68

TABLE 9. ANOVA analysis with CORTAUC (% change nmol/l°min)
and categorical variables for All Pigs data set and restricted data set
for Focus Pigs Only ................................................................................. 69

TABLE 10. AN OVA computation with mean and standard error of
HANTIME (minutes) and categorical variables ESTEEM, REPEATS,
Human gender (HGENDER), and Pig gender (PGENDER) variables ....................... 71

TABLE 11. Correlation analysis of HANTIME, PROBSOLV and RTHVOCAL
with rates of human behavior using the All Pigs data set ...................................... 72

TABLE 12. Regression analysis of mean and standard error of

human cortisol HCORT (nmon) and rate of handler behavior

for All Pigs data and the restricted

Focus Pig Only data set ............................................................................ 73

vii

TABLE 13. Regression analysis with dependent variable CORTAUC
(percent increase of cortisol by time (minute)) and human behavior for
All Pigs and the restricted Focus Pig Only data sets ........................................... 74

TABLE 14. Regression analysis of HANTIME estimated coefficient (i SE) and
different rates of All Pigs and Focus Pigs Only handler behavior ............................ 75

TABLE 15. Descriptive analysis of pig behavior variables for the All Pig data set ....... 75

TABLE 16. Correlation between pig behavior variables escape, turn, low grunts,
high grunts, and squeal to other rates of pig behavior for ALL PIGS data set .............. 77

TABLE 17. Regression analysis of mean cortisol HCORT (nmon) and rate of pig
behavior for All Pigs data and the restricted Focus Pig data set .............................. 78

TABLE 18. Regression analysis of HANTIME estimated coefficient (i SE)
and using All Pigs data and restricted Focus Pig Only data set ............................... 79

viii

LIST OF FIGURES

FIGURE 1. A schematic diagram of a student handler with three pigs in circuit .......... 40
FIGURE 2. Schematic diagram of a circuit containing three obstacles. .................... 40
FIGURE 3. Study area within MSU PALE pavilion ........................................... 41
FIGURE 4. Study area within MSU PALE pavilion ........................................... 41
FIGURE 5. Saliva collection ....................................................................... 43
FIGURE 6. Student handler moving pigs through the circuit ................................. 44
FIGURE 7. Cotton roll and cotton buds used for saliva collection ........................... 50
FIGURE 8. Serial dilution curve .................................................................. 54
FIGURE 9. Mean salivary cortisol at 4 minute intervals pre and post circuit .............. 56

FIGURE 10a. Cortisol concentration (nmol/l) without adjustment for basal levels ....... 61

FIGURE 10b. Cortisol concentration with adjustment for basal levels at percent increase
over basal cortisol concentrations ............................................................... 61

INTRODUCTION

The stockperson is the person most saliently identified with stewardship of livestock.
However, the role of the stockperson has changed over the last 50 years from one of sole
ownership of diverse independent family operations to that of an employee responsible
for one particular aspect of an industrialized, specialized and management-oriented,
production unit.

Attrition of hog farms has accelerated since 1980, reducing the total number of hog
farms by ahnost 77% (Boehlje et al., 1998). This reduction has also resulted in a shift in
pork production from the traditional farming regions of the Midwest to other parts of the
nation and world. These recent dramatic changes within the swine industry have shifted
the responsibilities of the stockperson from the owner-operator to that of the employee. A
large majority of these employees, however, do not originate from traditional farm
backgrounds (Martin, 1996) and oftentimes lack adequate pork production experience.

Traditionally, research targeting the pig industry has investigated disease control,
optimal pig space, nutrition, environment and genetics. However, to improve production

efficiency and animal welfare, technologies are best captured when incorporated by good

2

stockpeople. In support of this observation there is a growing amount of scientific data on
the factors that may influence the relationship between humans and animals (Seabrook,

1994; Hemsworth et al., 1986; 1992; 1994). Knowledge of this interaction may have
considerable implication on the welfare status of farm animals, and subsequently their
productivity. Seabrook (1984) determines that the stockperson, when handling the pig,
should give their livestock charges favorable stimuli and use negative stimuli only when
adopting the “boss” animal position. Positive handling, as defined by Seabrook (1984),
included touching and patting when handled, hand feeding and verbal communication.

Moving pigs prior to shipping improves overall willingness to move during the
handling process, whereas animals are more reluctant to leave a pen when left for long
periods of time within a barren environment (Abbott, 1997). In the smaller and
conventional systems, pigs move from the hot nursery to a cold nursery to a grower barn
and then finally into the finishing unit. Contrary to what we might expect, the
specialization of the industry has increased the time a pig will spend in the same pen. Pigs
are moved into combination “nursery-grower—finisher” units and remain in that pen for up
to 180 days before being handled again, increasing the fear response and likelihood that
pigs will be reluctant to leave the pens.

Communication between the sender and the receiver is not restricted between
members of the same species. Auditory, olfactory and visual signals are used when pigs
communicate and respond to humans (Grandin, 1993; van Putten, 1980). Therefore a vital
part of animal husbandry is to understand the behavioral patterns used by pigs. Thus
problem solving must be considered a necessary skill of all effective modern

stockpersons.

3

At present there is little scientific research identifying characteristics of experienced
and inexperienced stockpeople. Based on our current knowledge of the swine industry
and our present understanding of human behavior, the purposes of the present study are
threefold. The primary aim is to qualitatively evaluate human characteristics, self-esteem
and gender, and human behavior that improve the handling of pigs. Beyond that, the
study is designed to document human-pig interaction during handling in a simulated “on-
farm” environment. The final aim is to provide a quantitative foundation for the

establishment of criteria for selecting effective stockpeople.

LITERATURE REVIEW

The purpose of this review is to present research on the personality and behavioral
characteristics of the stockperson. The review and integration of relevant literature in
personality and social psychology is followed by a presentation of a traits that offer a
general framework for prediction of human behavior. The review also explores pig
behavior, indications of stress in both humans and pigs and ways in which the behavior
and productivity of livestock is interconnected with of action and handling ability of the

stockperson.

Handler Characteristics

The Foundation of Personality

Gordon (1963) defined personality as the enduring characteristics of the traits that
temper the individual behavior throughout their lives. Personality traits are defined “as a
characteristic of an individual that exerts pervasive influence on a broad range of trait
relevant responses” (Ajzen, 1986). Although humans are complex individuals, the

research consensus is that most of the individual differences can be summarized in terms

5

factors and a few examples of trait pairs that are representative of each of these factors
(Norman, 1963; Digrnan and Inouye, 1986) are as follows:

Extrovert: talkative-silent, frank-secretive, adventurous-cautious,

high esteem-low esteem.

1. Emotional stability: calm-anxious, poised-nervous, neurotic-secure.

2. Agreeableness: good natured-irritable; gentle-headstrong;

cooperative— negativistic.

3. Conscientiousness: tidy-unkempt, responsible-irresponsible

4. Openess: imaginative-simple, intellectual-non-reflective

These personality factors are expected to be manifested in behavior (Ajzen, 1988).
To use examples cited by Aj zen, people who are extroverted are expected to talk more
Openly; thus it is likely that the extrovert will speak more frequently in a group setting

and ask others for advice or assistance more freely.

Personality and the Stockperson

Seabrook (1972) conducted one of the pioneer efforts utilizing personality scores as a
basis for successful stockpersonship within the dairy industry. In this study, Seabrook
followed twelve, single-operator, dairy herds of similar genotype, building design, and
feeding program for a period of 6 years. Analysis of herd records revealed interesting
information of the effect of different stockpeople, with similar resources, on milk
production (liters/cow/day) and cow behavior. This study showed that substituting the

stockrnan of high producing farms with another stockrnan might result in a drop in milk

6
yield. Alternatively, changing the stockrnan of low producing farm usually resulted in a

marked increase in nrilk yield. Cows managed by the stockrnen of high producing farms
came into the parlor more easily than those farms with lower production. When the
stockrnen were assessed, by various techniques, for personality traits, Seabrook found the
stockman associated with high production yields and easily managed cows were
confident in their vocation yet introverted. This early interpretation of the high achieving
stockperson as “the confident introvert” suggests a correlation between the personality
traits and the positive interaction of the person with their animals. In a later longitudinal
study, Hemsworth et al., (1981a) evaluated the achievement of 12 different stockpeople
from farms with similar resources. The results suggest that the behavioral response of
sows to the presence of the human is positively associated with the reproductive
efficiency of the sows. He concluded that successfirl stockpeople are conscientious,
caring, eager to learn, humble and have good observational skills of pig behavior.

' Further work (Gonyou et al., 1986; Seabrook, 1991) revealed characteristics common
to good stockpeople including confidence, independence, consistency, low aggression
and stability. In a more recent study using a 16-trait personality test, Ravel et al., (1996)
performed a psychodemographic profile of 86 stockpeople from swine farms in Quebec.
Demographic data were obtained through interviews. The study population were
predominantly male and the participant criteria consisted of the stockperson solely
responsible and working within farrowing units. In general terms, all stockpeople
working in these farrowing units were high scoring on emotional stability, conformity,
self-discipline, and introversion. Based on the aforementioned research (Gonyou et al.,

1986; Seabrook, 1991; and Ravel et al., 1996), a personality composite of the stockperson

7

may be characterized as introverted, emotionally stable, serious, conscientious, reserved

and controlled.

Developing Personality and Behavior

Although evidence for genetic effects of behavior is available in lower animals
(Lagerspetz, 1979), these effects are determined by controlling the environment and
through selective breeding. Thus, due to ethical restraints, evidence determining genetic
effects for human behavior is not plentiful. The exception to this is population research
consisting of monozygous twins who share a common environment. Behavior between
twins provides evidence for genetic variability in human behavior. One such investigation
(Rushton et al. 1986) consisted of more than 500 pairs of monozygotic and dizygotic
twins who completed a questionnaire that assessed five personality variables: altruism,
empathy, nurturance, assertiveness and aggressiveness. Rushton et al., reported higher
correlations for the monozygotic twins for each variable. Further analyses from this data
indicated that approximately 50 percent of the variance for each variable was due to
hereditary causes, presenting evidence that behavior was heritable.

Some behaviorists, however, would argue that behavior is acquired through
experience, conditioning and learning. According to Hinde, (1987) there is a repertoire of
behaviors that is established through learning and individuals emulate the behavior of
other members of the society or subculture in which they live in attempt to gain social
acceptance. Baumrind (1971) investigated personality traits of children under different
parenting methods and determined that mother-child interactions, particularly maternal

warmth and maternal control, were good predictors of acquired attributes such as social

8

responsibility, independence, achievement orientation, vitality and energy level of the
child. For example, authoritative parenting, which is high in warmth and values both
autonomous self-will and disciplined conformity, resulted in children possessing
attributes such as social responsibility, independence, achievement orientation,
fiiendliness, and popularity. The attributes of independence and achievement orientation
were discovered to continue well into adolescence (Baumrind, 1991). In contrast, children
of authoritarian parental rearing, which values power and is lower in warmth, have been
observed to be withdrawn, unhappy, anxious, insecure when interacting with peers, and

obtained poorer grades in high school (Dombusch et al., 1987).

Self-esteem

Self-esteem, the evaluation of oneself, consists of a range of extremes from the
feeling of complete worthiness as a valuable member of society to the feeling of
worthlessness and valueless (McMartin, 1995). According to Pope et al. (1988), self-
esteem can be evaluated in several different areas such as: 1) social self: the person’s
feeling about himself as a friend to others, 2) academic self: the person’s evaluation and
standard of their performance as a student, 3) family self: a person’s feelings about being
valued and making contributions within the family unit and being secure in the love and
respect received fiom parents and siblings, 4) body image: a combination of physical
appearances and capabilities based on the satisfaction of both the way his body looks and
performs, ie athletic ability, and finally 5) global self-esteem: a overall general appraisal
of the entire self reflecting such feelings as “I’m a good person” or “I like most things

about myself” (Rosenberg, 1965).

9

Generally, when a person experiences success or failure, he assesses that
performance against an inner standard. Self-esteem is an evaluation of the information
contained in the self-concept and is derived from a child’s feelings about himself (Pope et
al., 1988). When the perceived and the ideal selves are a good match, the self-esteem will
be good (Higgins, 1987). Based upon this knowledge William James (1890) offered a
simple, profound, well-established, formula for self-esteem: Self-esteem =
Successes/Pretensions. Pretensions are the expectations we place upon ourselves.
Therefore, when successes exceed expectations, higher self-esteem results.
Notwithstanding, a person who does not excel in sports is not likely to feel unsuccessful
if that person does not value athletic skill (Pope et al., 1988).

According to Hinde (1987), respect from others has become essential to the sense of
self-esteem. The primary relationship within a group is highly significant in the
development of humans. Closely related to this is a person’s sense of belonging to or
frustration within a larger group within which that person closely identifies. This identity
to a group is an important contribution to one’s self-esteem, whether the group is a
nation, a tribe, 3 political entity (Campbell, 1965) or for our research, part of an animal

handling class.

Human Behavior

The premise of behavior, based on ethology, is the idea that behavior is pre-
programmed (Geen, 1990) and aggressive behavior such as butting, clawing, biting,

kicking, and slapping, are motor patterns reacting to aggression stimulus (Lorenz, 1966).

10

A simplistic yet basic premise is that aggression is the result of two variables (Geen,
1990). One variable is the state of the person in which one is capable of aggressing and is
ready to aggress. The other variable is that the situation elicits the aggressive behavior.
As with behavior in general, the state of the person, may be a result of a biologically
inherited aggressive temperament or a result of past learning. Lorenz (1966) maintains
that the aggression drive in humans is still a “hereditary evil of mankind”.

Montagu (197 3) and others argue that aggression is instead a learned response. A
review of studies investigating learned aggression in older children (Crowell, 1986) noted
that the interaction in families with aggressive children was characterized by the
exchange of negative, hostile behaviors whereas the interaction in families with non-
aggressive children tended to be mutually positive and gratifying for the parents and
children. Hinde (1991) explains that the individual is establishing a repertoire of
behaviors to be used in various situations, providing general capabilities which can then
be adapted by humans to further expand the repertoire of successful behaviors as new
events arise. Regardless of the debate, both the biological make-up and learning explain

behavior in humans and both play a role in creating the conditions for human behavior.

Problem Solving Behavior: The Human Endowment

Problem solving is defined as a generation of alternative responses and cognitive
strategies as well as decision making and behavior to find a solution (Anderson, 1993;
1996). Bransford and Stein (1984) suggest five components to problem solving: identify,
define, explore, act, and learn. The first component or step in problem solving is to

identify that a problem exists. The effective learner tends to recognize a problem, and

ll
gathers more information while inhibiting the tendency to respond either on the first

impulse or to do nothing. According to Anderson (1993), effective learners have greater
confidence (self-esteem) in their ability to control their environment and view the act of
identifying a problem as a good thing. Less effective learners and thus less successful
problem solvers tend to be impatient, impulsive and quick to give up if a solution is not
immediately apparent (Rotter, 1966).

Many problematic situations are ambiguous and inadequate in suggesting the proper
strategy or direction. Therefore after the problem has been identified, the problem must
be defined by thinking about all aspects of the situation, separating relevant from non-
relevant information, and to identify goals and specify maj or issues (Bloom and Broder,
1950). Bransford et a1. (1986), in a review of the literature, suggest that the successfirl
problem solvers tended to translate the difficult and unfamiliar terms into simpler, more
concrete terms, often substituting an illustration for a vague concept and then working
with the problem in tangible terms. Less successful problem solvers tend to take less time
to encode the initial problem information, accepting the vague concepts and ignoring the
unfamiliar ones (Bloom and Broder, 1950).

The definition of the problem then leads to the exploration of possibilities, and the
subsequent addition, deletion and modification of those possibilities. For example, the
effective learners tend to use different strategies when trying to achieve goals and are
further able to incorporate the appropriate “repair” strategies (Bransford et al., 1986).

After the problem has been identified and explored, the person must act on the
deemed strategies and look at the results of those actions. For example, Moser and Levy-

Leboyer (1985), observed people as they attempted to use a malfunctioned, coin-

12

operated, telephone. In one condition, an instruction on retrieving lost money was
provided, in another, no information was provided. The researchers observed that
aggressive behavior i.e. hitting, kicking, and slamming the phone was greater among

those with no information than those with information.

Measuring Personality, Self-Esteem and Problem-Solving Behavior.

Thus far this review has emphasized two theoretical perspectives that have
implications for understanding stockperson characteristics and actions. One involves the
role of the personality in predicting subsequent behavior and the second focuses on the
behavior of the handler in unfamiliar and unpredictable settings.

My

When self-awareness is heightened, the consistency between self-evaluation of
personality and overt behavior is increased (Ajzen 1988). In his text, Ajzen cites
examples of how heightened awareness during evaluation of personality can improve the
consistency between the overt behavior and the personality score. In one study, actual
punishment behavior using administration of shocks and the attitudes scores toward
punishment were highly predictive when a mirror was present during the actual
administration of shocks (correlation of 0.57 and 0.58 in repeated studies). In contrast,
respondents filing self-reports may unknowingly or knowingly misreport their behavior
and attitudes in a positive bias, especially in cases of socially desirable behaviors such as

high self-esteem.

13

SELf-Estzcm

Rosenberg (1965) developed a ten-item self-report scale as a measure of global
attitudes toward the self among adolescents. This scale, the reliability and validity of
which was examined based upon a normal distribution, was found to be a useful
unidimensional measure of attitude toward self (Carmines and Zeller, 1979) within
populations of similar age. If however, age varied substantially, this measure became
multidimensional and less reliable. Another hypothesis explained by Ajzen (1988) is that
consistency in behavior is greater when the situation exceeds the level of competence. In
one particular study, behaviors reflecting aggressiveness and withdrawal were observed
within emotionally challenged children. The participants were challenged with situations
that were either within their competency or exceeded their competency. Consistency of
behavior was higher when challenged beyond competency, suggesting that under stress,
humans are more likely to resort to a known, familiar repertoire of behavior.

Problem solving

In evaluating problem solving research has not yet discovered a conclusive
evaluation that easily distinguishes the differences between effective from less effective

problem solvers. Bransford et al. (1986), however, did discover that less effective learners

frequently experienced difficulties with each of the IDEAL components.

Behavior of the Stockperson
Earlier work on stockperson behavior in handling of pigs (Hemsworth and Brand et
al., 1981a; Hemsworth and Barnett et al., 1981b; Hemsworth et al., 1986; and Dryden et

al., 1986) investigated those behaviors commonly used by stockpeople and classified

14

these behaviors as non-aversive or aversive based upon the fear response of the pig. Fear
response was defined by withdrawal of the pig from the human (Hemsworth and Brand et
al., 1981a) or was measured based on the time required for the pig to approach and
interact with the handler or the experimenter (Hemsworth and Barnett et al., 1981b). On
farms where the sows were less fearful, the sows were also less restless, quieter, and
when comparing production measures reared a larger number of piglets than sows housed
in aversive conditions (Hemsworth and Brand et al., 19813). Where aversive handling
was used, breeding animals, both gilts and boars, approached humans less often,
exhibited retarded maturation rates to sexual development, and possessed higher plasma
corticosteriod levels (Hemsworth et al., 1986). Negative or aversive handling of pigs was
represented by such aggressive behavior as slapping, kicking, pushing and use of an
electric prod (Dryden et al, 1986).

Aggression levels, based on personal interviews and observation measures during
handling of piglets, were assessed for stockpersons on a large, multiple site, swine unit
(Seabrook, 1994). The aggression scores of 56 employees ranged from a low of 2.4 to a
high aggression score of 7.6. A significant correlation was discovered between higher
aggression scores and reports that working with pigs was frustrating or the feeling that
present job responsibilities did not allow enough time to handle pigs in a pleasant
manner. Comments made in this study, by the stockpeople with higher scores include: “It
is a highly frustrating job’, ”It ’s not easy being nice when they are going the wrong
way. or “ The pressure is great so I lose my temper.”

Whether a certain behavior is considered to be aggressive may depend on expression

of pain, occurrence of injury, or the actual intention. Individuals that elicit aversive

15

responses should not be defined as aggressive based solely on behavior indicators of pain
or escape. Piglet castrations, which most stockpersons would not consider aversive, elicit

pain responses such as vocalization and tail wagging (Noonan et al., 1994).

Pig Behavior in Response to the Handler

Stimuli fiom social interaction with conspecifics include the interacting forms of
behavior such as submission and dominance, and these sign-stimuli are recognized by
respective conspecifics (Gray, 1987).

Auditory communication

Vocal signals are an important means of communication in the pig, and can be
simply divided into two main categories of low and high tonal vocalization. Fraser (1974)
investigated the tone, length, and frequency of vocalization of juvenile pigs in response to
an isolation treatment. The study reported that short (0.25 to 0.4 seconds) low-tonal
grunts were associated with overall low frequency of vocalization. Moreover, long grunts
(>0.4 seconds) and squeals were associated with greater overall vocalization and
increased locomotor activity. At high levels of excitement, vocalization tend to be longer,
louder and of higher tonality, and can be classified as high grunts and squeals (Kiley,
1972). According to the Canadian Council on Animal Care (1993), the squeal, a more
intense and higher pitched vocalization, is described as one of the key signs of pain and
distress in pigs.

Kiley (1972) recognized that pig communication is not easily categorized and

suggests that vocalizations of pigs are part of a continuum of sound that functions as an

l6

analogue system reflecting the “level of excitement”. Apparently, similar tonal
vocalization can communicate both pleasure and distress in pigs. For humans
understanding pig vocalization must include a combination of auditory cues and observed
activity. Recent research (von Borell and Ladewig, 1992) concurring with the earlier
results of Fraser et al., (1974) demonstrated that high-pitch vocalization and increased
locomotor activity were correlated. Moreover, this study revealed that a greater frequency
of grunts and squeals were oflen accompanied with escape attempts.

Olfactog communication

Olfaction in pigs is important in establishing social hierarchy, reproductive status,
and individual recognition among pigs (Meese and Baldwin, 1975; Fraser and Broom,
1990). When pigs are first introduced to a novel environment, they nose and root
inanimate objects. If the environment includes unacquainted pigs, they will initially push
and touch the pigs until finally a fight ensues resulting in pigs standing face to face
followed by attacks predominately to the ear (Fraser and Broom, 1990). Studies in
olfactory communication (Meese and Baldwin, 1975) reveal that the pig can distinguish
the urine of one pig from another and that aggressive interaction was reduced when pigs
were deprived of their olfactory bulb. McClone and Morrow (1988) showed that when
urine containing pheromones from a handled or stressed pig was sprayed on fighting pigs
there was an increase in submissive behavior. This was confirmed by Vieuille-Thomas
and Signoret (1992) in another study which determined that, at a feeder space, the
presence of urine from a stressed animal would result in avoidance of that feeder space by

other pigs.

17

Visual Acuig

Similar to olfactory cues, visual cues involved in social recognition (Ewbank et al.,
1971), may also contribute to the formation of stable hierarchies and reduction of
aggressive interactions. Pigs have been shown to possess color vision and are able to
discriminate between wavelengths of light differing by only 25mu (Klopfer, 1966). In a
review article Grandin, (1988) states that pigs have a natural tendency to move toward an
illuminated area but will balk if the light is cast into the pig’s eyes or if there are shadows
cast in the alley or chute. She also notes that pigs have visual depth perception, which can
result in balking when approaching a puddle or a change in floor surface.

The flight zone of an animal is that space surrounding the animal that will elicit
avoidance or escape behavior when physically encroached upon. If the stockperson stands
within the flight zone, pigs will move away fiom the stockperson, whereas pigs will cease
to flee when the stockperson retreats from the flight zone (Grandin, 1987). Results from
Muira et al (1996) investigating the flight zone and withdrawal response of the pig to
humans, showed that the blind spot of the pig is at an angle of 90°-105° behind the pig,
leaving 255° to 270° of vision. According to Muira et al., no escape behavior was
observed while the human kept beyond a distance of 1.2 m from the pig. It should be
noted however, that animals may engage in forms of behavior, which are neither

approach or avoidance behaviors.

l8
Breed and Genetic Variabilig

Not all animals respond to the same stress or novel stimuli in a predictable manner.
One study by von Borell and Ladewig (1992) demonstrated a high degree of behavioral
variability between pigs, yet a consistent adrenal response to adrenocorticotropin
hormone (ACTH) treatment within individual pigs over a 14—week testing period.
Behaviorally, those individuals with a greater adrenal response were consistently more
excitable with increased vocalization, locomotion, and escape attempts.

Individual differences, not environmentally determined, but showing a genetic
relationship have been demonstrated in mice (Benus et al., 1991). Mice, raised in
identical situations, were divided into those who cope in an active manner and those who
cope in a passive manner. Active copers respond to social and non-social stressful
situations using the sympathetic system, which is physiologically characterized by
increased blood pressure and higher levels of catecholamines and corticosteriods.
Conversely, the passive copers respond to similar stimuli predominately
parasympathetically which is associated with low blood pressure, and lower levels of
catecholamines and corticosteriods. The behavior of the active copers tends to be more
aggressive, exhibiting a higher number of escape attempts and a predisposition to develop
routines. In a similar study, Hessing et al. (1993) divided pigs into two groups, resisting
and non-resisting, based on the piglets’ compliance to being held on their backs.
Resembling the active and passive coping strategies of mice, resisting pigs were more
likely to be more aggressive and consistently showed more escape attempts over time.

Yet Jensen and Forkman et al., (1995) have criticized this work stating that the

19
distribution of escape attempts of resisting and non-resisting pigs tends to be unimodal

with rather low consistency over time.

Breed of the pig also affects behavior during handling. One study showed that
Yorkshire hogs required more time to load than Pietrain (Marshal-Nimis and Rempel,
1986) and it is thought that Landrace pigs with long ears often balk because they have
difficulty seeing (Grandin, 1987).

Hemsworth and Barnett et al. (1990) determined fearfulness in gilts on the basis of
avoidance behavior such as the flight response and whether or not the gilts physically
interacted with the experimenter. Fear response in gilts was determined to be moderately

heritable.

Handling of Pigs

Lambooij and van Putten, (1993) simulated handling for transport by placing pigs in
a circuit containing various obstacles. Because social isolation is stressful for pigs, each
test pig was accompanied by some of it’s pen mates through the circuit containing
obstacles such as ramps, darkened areas, single file runs, and frmnel crowd pens. Pigs
were also coaxed forward with an electric prod. Using an increased heart rate as an
indicator of stress, ascending a ramp was determined to be more stressful than electric
prodding or descending the ramps. At a loading ramp angle of 30° heart rates reached
220-240 beats per minute. Mayes and Jesse (1980) also found that heart rate was greater
when a pig climbed a ramp compared to descending it. They also discovered that the pig
will stop or lie down when their heart rates exceeds 220 beats per min. The difficulty

seems to be primarily psychological for pigs inexperienced in climbing a ramp. The pig

20

may perceive the ramp as a wall. The animals refuse to try to climb and will turn their
bodies sideways to the ramp. By decreasing the ramp angle to 15°, loading became easier
for inexperienced animals.

This same study by Mayes and Jesse (1980) revealed that when a pig was prodded it
attempted to escape by moving forward or running back into the middle of a group of
pigs. Pigs were often observed attempting to return to the pen they had most recently left.
Pigs would also still turn back towards an opening, even if it was only 5 cm wide. In
addition, pigs were observed balking and turning around when the handler attempted to
drive them down an alley where people were visible ahead. They would often balk and

refuse to enter a crowd pen or single-file race if people were seen standing next to it.

Pigs will follow other pigs and maintain both body and visual contact (van Putten
and Elshof, 1978). While moved into the single file race and through the funnel, all pigs
attempted to move at the same time. However, pigs moved more readily if the handler
detected the animals closest to the single-file race entrance and moved that pig into the

race opening first, instead of pushing a large group of pigs from behind.

Spatial Memory in Pigs

Although there is very little research dedicated to spatial memory in pigs, studies
have investigated spatial memory in red deer and cattle. Rushen (1986) noted that deer
were able to associate an aversive stimulus to one arm of a maze. In another study, cattle
appeared to have difficulty in reversing a previously learnt spatial association between an

aversive stimulus (Grandin et al. 1994). In a more recent experiment, Mend] et al. (1997)

21

determined that pigs were able to search for food sources and remember the location

across 10 minute and 2 hour retention intervals.

Handler to Pig Vocal Interaction

Animals respond to human vocalization (McConnell, 1991), thus the use of the voice
is a useful means of interaction with animals. According to Seabrook and Bartle (1992),
talking to animals is a reflection of the stockperson’s empathy toward pigs and
stockpeople with less empathy and high aggression scores spent less than 15 minutes per

day talking to the animals in their charge.

Handler Posture

Hemsworth et al. (1989) reported that a human standing in an erect posture was more
threatening to breeding pigs than a human in a squatting posture. Muira et al., (1996),
examined the influence of human posture and movement on the approach and escape
behavior of weanling pigs. By measuring the time taken by the pig to approach a dummy
in a standing position, stooping position, or lying face down, this research determined
that the pigs spent significantly more time in close proximity of the dummy lying down

than in the standing erect posture.

Stress Response in Humans and Pigs

Stress is generally considered the physical and psychological state in response to

emotional or environmental stimuli. When humans and animals are confronted with an

22

environmental change, adaptation involves a range of behavioral and physiological
responses that function to maintain homeostasis. Therefore the individual’s perception of

whether the experience or environment is stressful may vary.

Physiological Response to Stress

Animals confronted with a challenging situation due to increased physiological or
psychological demands, respond to stress through the use of three major biological
systems: autonomic systems, neuroendocrine systems and behavior (Moberg, 1987).

Response of the autonomic nervous system is part of Cannon’s (1929) proposed
flight or fight response to stress. The emergency reaction is due to the sympathetic
nervous system acting in conjunction with catecholamine hormones, norepinephrine and
epinephrine, secreted fiom the adrenal medulla. The function is to alter biological
systems (cardiovascular, gastrointestinal, musculo-skeletal and immune) such that there is
increased heart and respiratory rate, shunting of blood supply from the viscera to the
muscles and the brain and margination of lymphocytes to improve healing. The response
of the autonomic system is so rapid, that plasma hormonal concentration return to basal
levels very quickly, making adrenaline and noradrenaline difficult to interpret in a clinical
setting.

The “general adaptation theory” as described by Selye (1952) states that after the
fight or flight response there follows a stage of resistance during which resistance to the
original stress increases but the resistance to new stress is lowered. If stress is prolonged,
glucocorticoids are released from the adrenal cortex under the control of ACTH fi'om the

anterior pituitary gland. ACTH has received attention in stress research because it is

23

released during a variety of stressful situations such as injury, social interaction, physical
restraint and transportation and may modulate biological systems such as reproductive,
growth and immune response (Guyton, 1996). ACTH secretion is largely controlled by
corticotropin releasing hormone (CRH), and the presence of hormones, neurotransmitters
and receptors common to the endocrine, immune and CNS. It is believed that these
systems interact in a coordinated manner (Gray, 1987). CRH, identified in the limbic
areas of the brain (hypothalamus, thalamic nuclei, amygdala, and hippocampus), plays a
role in activating endocrine, physiological, neurochemical and behavioral responses
typically observed in stress responses (Vale et al., 1981). CRH activates the
hypothalamic-pituitary-adrenocortical (HPA) axis, sympathetic and adrenomedulary
system (Brown and Fisher, 1985) stimulating synthesis and release of the adrenal
glucocorticosteriods: corticosterone and cortisol.

The glucocorticoids promote the transformation of non-sugars into sugars
(gluconeogenesis) and increased glycogen storage, providing easily mobilized sources of
energy. Glucocorticoids are also anti-inflammatory agents, delaying the growth of new
tissue, inhibiting formation of antibodies, lowering lymphocyte counts (Vining and
McGinley 1986). Other stress induced changes include marked inhibition of body growth,
reduced production of spermatozoa, reduced secretion of testosterone by the testis and
delay or complete suppression of puberty. Chronic release of glucocorticoids results in
disruption of menstrual in primate females or disruption of the heat cycle in non-primate
mammals, decreased uterine weight and failure to ovulate or implantation of the fetus due
to a negative feedback reducing the secretion of follicle stimulating hormone (F SH)

(Guyton, 1996). Hemsworth et al. (1989) demonstrated lower reproductive efficiency in

24

gilts and young boars subjected to aversive handling three times per week over a period
of 12 weeks. The boars were slower to reach puberty, complete matings and had smaller
testis, while the gilts exhibited lower fertility rates when compared to breeding stock
handled in a pleasant manner.

Unlike the short half-life of catecholamines, corticosteriod levels in plasma and
saliva, can have a half-life of approximately 20 minutes (Blackshaw and Blackshaw,
1989). While cortisol concentrations tend to be episodic in pigs, humans cortisol levels
are less episodic (Guyton, 1996). In clinical studies using human subjects, it was noted
that the response between individuals varies. Some people show a brisk increase in
cortisol secretion whereas others show little or no response. Moreover, if an individual is
again exposed to the same stressor, psychological distress may be reported but is not
usually accompanied by continued endocrine change (Pollard, 1995). This relatively

quick adaptation to initial stressors is widely acknowledged.

Physiological Indicators of Stress

Salivgy Cortisol

Assessment of cortisol has frequently been used as an indicator of hypothalamic-
pituitary adrenal (HPA) activity. Cortisol is a small, hydrophobic molecule present in all
bodily fluids.

The stress of venipuncture has been shown to increase cortisol levels whereas saliva
sampling has not (Vining and McGinley, 1986; Kirschbaum and Hellharnmer, 1989). The
limitations of various criteria used to assess welfare are widely recognized. The

measurement of cortisol in saliva provides a reliable tool for investigation of

25
hypothalamus-pituitary-adrenal axis activity. Cortisol is the main glucocorticoid

hormone, in both humans and pigs, being produced by the adrenal cortex. It is released in
response to various biochemical agents and pyschosocial stimuli (Kirschbaum and
Hellharnmer, 1989). Fortunately, saliva flow rate does not effect saliva cortisol levels
(Hubert and de Jong-Meyer, 1989).

The reliability of using saliva instead of blood as a body fluid to determine the free
fiaction of low molecular weight hormones, such as steroids, has been well established
(Walker, 1989). The measurement of cortisol in saliva offers several advantages over
blood sampling: saliva is easily collected using non-invasive methods; it is non-stressful
to collect; easy to perform; and plentiful in supply (Cooper et al., 1989; Kirschbaum and
Hellharnmer, 1989; Parrott and Misson, 1989; Cook et al 1996; Fenske, 1997).

Salivary cortisol indicates the free, biologically active concentration of this particular
glucocorticoid and is positively correlated with plasma levels. Cook et al., (1996)
compared efficacy of salivary cortisol analyses for assessment of the HPA response to
exogenous ACTH stimulation as compared to serum cortisol measurement. Significant
correlations were established between serum and salivary cortisol values. Moreover,
salivary "free" cortisol may prove to be a better indicator of stress than "total" cortisol
measured in blood samples due to lower variation of cortisol-binding globulin (CBG)
found in salivary cortisol. Less than 90% of circulating plasma cortisol is bound to a
major binding protein called CBG plasma proteins (Parrott and Mission, 1989). In
humans, approximately 4.0 % of cortisol in humans is unbound. In pigs, the levels of

cortisol in saliva are approximately 10% of the total plasma cortisol (Cook et al., 1996).

26

Since salivary cortisol is not bound to proteins, this concentration level was not altered
when measuring cortisol in women using oral contraceptives (Walker, 1989).

Saliva is produced by three major groups of salivary glands: the parotid;
glossopharyngeal, submandibular and sublingual glands; and several accessory glands
distributed throughout the oral mucosa. The accessory glands secrete saliva continuously
and are under local control. The major gland's secretion is mediated mainly by
parasympathetic activity in response to physical, chemical and psychological stimuli.

How steroids enter in the saLva

Vining and McGinley (1986) reviewed two mechanisms which have been postulated
for the transference of steroids from plasma to saliva: A) Inna-cellular diffusion, which
takes place into the lipid-rich cell membranes of acinar cells or into the cells lining the
gland as a result of lipid solubility of steroids; and B) Ultrafiltration, the process by
which unbound steroid fractions may be carried by water which passes between the tight
junctions between acinar cells. Both processes allow only the passage of unbound

steroids.

Behavioral Response to Stress in Animals

The physiological response of an animal may be a coping strategy in stressful
situations and not necessarily evidence of a harmful effect of the stimulus or an indication
that the animal is experiencing distress (Moberg, 1987). Therefore, changes in adrenal
cortical responses must be correlated with a change in coping strategies and animal

behavior.

27

Behavioral response of stress in animals may include the occurrence of destructive,
stereotypic, inactive, and escape behavior (Fraser and Broom, 1990). Despite the obvious
indication, these behaviors are not necessarily harmful for the animal but may be helpful
in enabling the animal to cope with stressors.

Conflict behavior in animals may include both destructive and normal behavior.
Destructive behavior are those causing mutilation to other animals such as feather
pecking in poultry or tail biting in pigs (Broom, 1993). Stereotypic behavior is behavior
repeatedly performed by animals without apparent purpose including tail chasing in dogs
and sham chewing in pigs. This displacement activity or coping behavior (Broom et al.,
1995), may be a response to aversive situations. Displacement or redirected behavior
performed in an abnormal frequency may also include such normal behavior as
grooming, feeding and sleeping. Willingharn (1956) found that in mice, a normal
behavior such as grooming was one of the major responses to fear stimuli. Other
“normal” behaviors such as lying down and massaging of penmates were increased for
pigs kept in barren environments (van Putten, 1980). It is suggested that these strategies
have been shaped by evolution as adaptive measures to fitness-threatening situations with
which animals are confronted in their natural environment (Wechsler, 1995).

This may explain why there is little evidence to confirm a relationship between
abnormal behavior and production performance (von Borell and Hurrrik, 1991) or
evidence that stereotypic behavior is detrimental to animal health status. Wiepkema et al.,
(1987) reported that veal calves housed individually and showing stereotypic behavior

had a lower incidence of abomasal ulceration.

28

Animals use various strategies to counteract aversive situations. Hemsworth et al.,
(1996) showed that daily injection was not physiologically stressful to pigs, speculating
that the pig’s ability to physically withdraw fi'om those injecting, enabled the animals to

cope without activating the hypothalamic-pituitary-adrenal axis.

Environmental Enrichment

Environmental enrichment through the use of toys or other investigative materials
may be another method used to maintain homeostasis during stressful situations. Dantzer
et al., (1983) have shown that pigs able to chew a chain in a conflict situation have lower
plasma corticosteriod concentrations. Pearce et al., (1989) found that pigs handled
aggressively during rearing were significantly more fearful of humans than pigs handled
in a positive manner. However, pigs housed in enriched pens reduced their fear regardless
of the handling treatment. In the enriched environment, the positively handled pigs

showed more exploratory behavior.

Human-Pig Interaction

Within pig production there are many opportunities for the stockperson to interact
with the pig, particularly with the breeding stock and the young pig. Indications of a good
stockperson are based upon the individual’s knowledge and understanding of livestock
behavior and physiology, application of pertinent skills, sensitivity and recognition of
abnormal behavior and the ability to prioritize responsibilities based on animal welfare

(English et a1, 1988). Research indicates that the productivity of the animal is related to

29
different, positive or negative, interactions used by stockpeople (Hemsworth et al., 1981a,

1986a, 1986b, 1987, Gonyou et al., 1986). There are specific human characteristics, such
as personality and attitude, common to good stockpeople (Hemsworth et al., 1989, 1994,
Seabrook 1990 and Ravel et al., 1996)

One of the first research studies in the area of interaction between pigs and the
stockperson was a study of 12 one-person operated commercial sow herds under single
ownership, which were similar in terms of location, buildings, genotype, herd size,
feeding and management advice (Hemsworth et al., 1981b). Despite similarities, the
reproductive performance between herds varied more than 20.0 percent. To explain the
differences, sows from each herd were tested for their withdrawal response to an
experimenter’s hand reaching to touch the side of the sow’s snout. The sows were also
tested individually for time taken to approach the experimenter. In these tests, gilts and
first parity sows were more cautious to interact with the experimenter. Using productivity
records corrected for parity, researchers observed a significant correlation between
increased avoidance behavior of sows with the experimenter to a lower number of total
live born piglets per sow. Since the sows responded in a similar manner to the
stockperson as the experimenter, the results from this study suggest that the reproductive
performance of sows is associated with the relationship developed between the
stockperson and the breeding stock.

Factors that may influence this response are the quantity and quality of animal
handling by the stockperson. Handling may involve physical, visual, auditory and

possibly olfactory contact between the stockperson and the livestock.

30
Quantity and quality of handling

Studies in poultry demonstrate that regular handling by humans increased approach
to humans (Jones and F aure, 1981), improved growth and feed efficiency (Gross and
Siegel, 1979: Jones and Hughes 1981; Hemsworth et al., 1989), and increased resistance
to pathogens (Gross and Siegel, 1990). In further studies, general fearfirlness and fear of
humans was negatively associated with production parameters in laying hens (Jones and
Hughes, 1986). Regular handling, known to reduce chicken’s fear of humans (Jones and
Faure, 1981), has also been associated with improved feed conversion efficiency,
resistance to infection and growth rate in young layer and broiler chickens (Gross and
Siegel, 1979; Jones and Hughes, 1981; and Gross and Siegel, 1990). Conversely,
Freeman and Manning (1979) found that regular handling depressed growth rate in layer
chickens.

There is evidence that the mechanism responsible for the depression in performance
is likely to be a chronic stress response (Hemsworth et al., 1992). A study to measure
behavior and growth performance in growing pigs, Hemsworth et al., (1981a)
demonstrated that a handling regime consisting of regular aversive treatments, which
consisted of a brief shock using an electric prod, resulted in increased avoidance of pigs
to the handler and reduced growth rate in juvenile pigs.

Even pigs that are subjected to daily husbandry procedures such as injection are
likely to respond with a lower corticosteriod response when compared to those pigs
treated in an aversive manner. Hemsworth et al., (1996) subjected pigs to 4 treatment
groups daily for three weeks. One group was handled in a positive manner, patting and

stroking, the second group was handled in a neutral manner with minimal handling, the

31
third group was subjected to aversive handling such as an electric prod and the fourth

group was injected intramuscularly with saline. Pigs aversively handled showed higher
corticosteriod, ambulation and adrenal gland weights and had a higher number of escapes
when compared to the injection group.

In a series of studies, juvenile pigs were exposed to two different treatments: a
positive treatment involving the stroking of pigs as the pig approached the experimenter
and a negative treatment involving forcing the pig away with either slapping or electrical
shock whenever the pig approached the experimenter. The treatments were imposed three
times per week from 11 to 22 weeks of age (Hemsworth et al., 1981a and 1987) and from
7 to 13 weeks age (Gonyou et al., 1986). In all three experiments, the unpleasantly treated
pigs showed a fear response to the handler, had higher glucocorticoid levels, and
exhibited significantly slower growth rates than pigs treated positively.

Handling of pigs early in life reduced the fear of humans in pigs at a later age
(Hemsworth et al., 1986a). However, there are inconsistencies in the handling of pigs
throughout the lifespan of the pig. Hemsworth and Barnett (1992) showed that the initial
effects of early human contact on subsequent behavior may disappear with time or that
the effects of present human handling may outweigh earlier handling.

Other work measured the behavioral and physiological response in juvenile pigs to
three treatments (Hemsworth et al., 1987). In this study, the treatments consisted of the
positive treatment of stroking the pig’s head, the negative or unpleasant treatment of
slapping the pig or an electrical shock as the pig approached the experimenter. The third,
an inconsistent treatment, was a combination of positive to negative treatments imposed

at a ratio of 1:5. The three treatments were imposed for three minutes each, three times

32

per week from 7 to 13 weeks of age. Unpleasant and inconsistent handling treatments
resulted in an overall lower growth rate and feed conversion (P <0.05), higher
corticosteriod levels and less approach behavior when compared to those pigs in the
exclusively positive treatment group.

Hemsworth et al. (1994) investigated stimulus generalization in pigs to humans,
testing the pig’s ability to discriminate between handlers. In this study, two handlers of
different height and body weight used varied handling regimes. Handler #1, a male of 1.7
m and 65 kg, used predominantly negative behavior at a ratio of negative to positive
interactions of 4:1, while handler #2, a female of 1.55 m and 59 kg, used a predominately
positive to negative interaction ratio of 4:1. A third handler who had little previous
exposure to either group of pigs later moved the pigs down a corridor. The pigs of the
negative handling group were most difficult to move by the third handler, as measured by
the mnnber of balks by pigs and number of negative interactions required to move pigs
through. This study proposed that in situations where pigs were handled in two markedly
different manners, the behavioral response to the negative manner will extend to other

humans.

Summary

The view of the stockperson is most saliently identified with stewardship of the
livestock. However, it is only in the last ten years that the interconnection of the
stockperson with animal welfare and productivity has received scientific attention in an

effort to provide quantitative information. This review describes the ways in which

33

human pyschosocial and physiological characteristics and behavior might influence the
physiology and behavior of livestock.

Much of the behavior of the stockperson toward domestic animals is based on both
human personality traits, innate and learned behavior. A personality composite of the
stockperson may be characterized as introverted, emotionally stable, serious, and
conscientious.

A compilation of such traits can be found in those with good self-esteem. Self-
esteem enables people better able to tolerate uncertainty, incongruity, ambiguity, or
inconsistency with new experiences and more readily solve encountered problems, which
in turn reduces frustration and anxiety.

When a problem solver reaches a state in which no adequate problem-solving
information available, the problem solver will revert to a repertoire of information that
will produce success, provide positive reinforcement and facilitate effective behavior,
thereby increasing self-esteem. Self-esteem is a variable studied within human ethology
and has been a useful tool in predicting human behavior.

Investigations of those behaviors commonly used by stockpeople were classified as
non-aversive or aversive based on the fear response of the pig. Animals use various
strategies to counteract aversive situations.

The response of pigs during handling may provide the stockperson with important
information of pig welfare and stress. Vocal signals, simply divided into two main
categories of low and high tonal pitches, are important means of communication in the
pig. Low pitched vocalization is generally associated with less locomotion and thereby

less stress, while high pitched vocalization such as squealing, is associated with increased

34
locomotion and stress of the pig. Olfaction in pigs is important in establishing social

hierarchy, reproductive status, and individual recognition among pigs. Investigation
behavior that includes nosing and rooting and avoidance of an area also provides an
indicator to the handler of the novelty or enviromnental stressor.

When moving pigs, the stockperson can use the pig’s vision to establish a flight zone
to elicit avoidance response of the pigs when physically encroached upon. Ethological
understanding of the pig’s natural tendency to move toward an illuminated area, yet balk
if the light is cast into the pig’s eyes or causing shadows in the passageway, provides
basic information on how to prepare the loading area before attempting to move pigs.
Pigs also have visual depth perception which results in approaching a puddle or a change
in floor surface with caution.

An animal’s response to the stress may vary depending on genetic predisposition,
novelty of the stimuli and previous experience. Animals confronted with a challenging
situation due to increased physiological or psychological demand, respond to stress by the
autonomic systems, neuroendocrine systems and behavior coping strategies.

When prolonged, stress due to social interaction, physical restraint and transportation
stimulates the release of glucocorticoids from the adrenal cortex. This glucocorticoid
release, under the control of ACTH from the anterior pituitary gland, may modulate
biological systems such as reproductive, growth and immune response

Measuring of cortisol, the main glucocorticoid hormone in humans and pigs, via
saliva sampling is easily collected an a non-invasive, non-stressful manner. Saliva
sampling also provides "free" unbound cortisol, a better indicator of stress than "total"

cortisol measured in blood samples.

35
Within pig production there are many opportunities for the stockperson to interact

with the pig. An indication of a successful handler is based on the ability of an individual,
by application of their skills, to optimize the productivity potential of the livestock.
Research indicates that the productivity of the animal is related to different, positive or
negative, interactions used by stockpeople. These interactions, when perceived as
aversive by the pig, invoke a fear response by the pig decreasing efficiency of handling.
There is also evidence that the mechanism responsible for the depression in productivity
performance is likely to be a chronic stress response of negative or aversive handling

techniques.

HYPOTHESIS

The overall purpose of the study were three fold.

1) To qualitatively evaluate human characteristics and behavior that improve the
handling of pigs.

2) To document human-pig interaction during handling in simulated “on-farm”
environment.

3) To establish criteria for selecting effective stockpeople.

Based on information from the purpose and a pilot study on human to pig interaction
the following hypothesis was tested:
Stockpeople who use a higher proportion positive problem solving tactics while

moving pigs through an obstacle circuit will minimize the stress responses of the pig.

36

MATERIALS and METHOD

Study Population

Of 140 animal science students enrolled in an animal handling come at Michigan
State University, 113 (81% response rate) completed a questionnaire and self-esteem
scale survey (see Appendix 1). The purpose and the design of the study were described
and the students were invited to complete a questionnaire and survey during 15 minutes
of class time.

Open questions were used to obtain the gender, age, ethnicity, community
demographics, and prior experience with domestic pets and experience handling
livestock. Due to the diverse backgrounds of students enrolled in animal science, it was
expected that there would be both experienced and inexperienced pig handlers. Forty
students were selected to participate in the study. Eight people failed to attend the
allocated lab times and therefore were not included in the study.

The survey, developed by human psychology researchers at Michigan State
University and used in a campus wide study of 4,000 freshman students, uses the

Rosenberg (1965) Self Esteem Scale which obtains information regarding a person’s

37

38

sense of self-esteem, competence, resilience, trust and warmth in a relationship. The scale
is composed of 58 statements concerning an individual’s evaluation of himself or herself
(e. g. “On the whole, I am satisfied with myself”). Subjects rated the extent to which they
agreed with each statement using S-point scales on which 1=strong disagreement and
5=strong agreement. The ratings for statements were later summed, with negative
statements reverse coded. Higher scores represented higher levels of self-esteem and
lower scores representing lower levels of self-esteem.

In this study, the self-esteem scores ranged from 1.0 to 5.0 with the scores of 1.0 to
3.8 representing the group and scores of 4.6 to 5.0 represented the group.

The scores of the subjects of this study were compared and found to be a
representative sample of the campus wide population (Aronoff, personal communication).
Students selected to continue in the study were chosen from the highest and lowest 33%
percentile scores and both groups were matched based on gender, day of study, and time.

Prior to moving pigs, all students were shown the direction to move the pigs and the
position of each obstacle was identified and the reason pigs would perceive this area as an
obstacle was explained. Each student handler was instructed to move three pigs through
the circuit (Figure 2). The students were given a pig board or gate (Figure 3) and were
allowed to use whatever method or gestures they perceived necessary to perform the task,
within the normal range of pig welfare. There were no time restrictions, however if the
task was not completed after eight minutes, the students were asked if they preferred to

continue or to resume the experiment.

39
Circuit Design

The study was held at the Michigan State University Pavilion for Animal and
Livestock Education (PALE) facility (Figure 3). The pavilion arena (2100 square meters)
was illuminated under artificial ceiling lighting. The flooring material throughout the
arena (20 cm depth) was a mixture of sand and topsoil. The study was conducted over
two days (Tuesday April 22"" and Thursday April 24'”) consisting of three time intervals
(10:20 am, 12:40 pm. and 3:00 pm.) on each day.

A circuit (Figure 4), composed of metal gates (1.8 meter length by 1.0 meter height),
measured approximately 9.1 meters on the inside diameter and 11.0 meters on the outside
diameter. The width of the passage area for handler and pigs ranged from a bottleneck
0.43 meters to 2.25 meters depending on the placement of the obstacle. The length of the
passage area contains solid white plastic panels (0.9 meters ) to obscure the pig’s view
outside the passage. The circuit contained 3 obstacles similar to an on-farm or pig
transportation situation. One obstacle included a wooden ramp with 0.9 meters on both
rise, 1.63 meters in length, 0.43 meters in height and 2.5 cm cleats placed every 8-9 cm.
The second obstacle was a square black garbage bag, 2.4 square meters, representing a
slightly slippery floor surface and the third obstacle was a narrow passage region or
bottleneck 0.43 meters in width. On day one, the first obstacle was a wooden ramp
followed by the black garbage bag and then the bottleneck. To minimize the learning
affect by the pigs which were studied twice, the circuit was reversed on day two (2 days
later) with the bottleneck, garbage bag and ramp as first, second and third obstacles

respectively (see Figure 2).

40

Figure l. A schematic diagram of student handler wearing green coverall, black
Wellington boots and holding a gate before three pigs.

 

Figure 2. Schematic diagram of a circuit containing three obstacles. A wooden ramp
with a 27 ° angle, a black garbage bag as a slippery surface, and a narrow passage
(bottleneck) region. The circuit is designed to observe pig behavior, human-pig
interaction and human behavior while pigs are moved by the student handlers.

Symbols:

Direction of pig flow on first day of study (Tuesday) with ramp, garbage bag and
bottleneck respectively.

Direction of pig movement on second day of study (Thursday) with bottleneck,
garbage bag and ramp respectively.

. Placement of human observers for pig recording of pig behavior.

I Placement of video cameras for human-pig interactive recording of behavior.

a

99

 

.....w,

Holding and sampling pens

42

Figure 3. Photograph of study area within the PALE pavilion at MSU.

 

43

Figure 4. Photograph of pigs in sampling pens within PALE pavilion at MSU.

 

Animals

Sixty pigs of mixed genotype (Large White/Landrace/Hampshire) were used in this
experiment. They were either castrated males (n=26) or females (n=70). The animals
weighed between 70 kg to 90 kg. Prior to the experiment pigs were housed 15 to 16 pigs

per pen in a conventional temperature control facility with concrete slatted flooring.

Experimental Protocol

On evenings prior to both days of the study, the pigs were individually identified
with large numbers (approximately 30 to 40 cm), using wax crayon markings, on their
back and both flanks. In addition, saliva samples were collected two days prior to the
study to allow the pigs to become accustomed to the samplers and procedures of saliva
collection. Since pigs can discriminate based on colour alone (Klopfer, 1966), importance
was placed on the consistency of appearance of each person handling the pigs. Therefore,
the person who sampled prior to the study were the same people who sampled the pigs
during the study and green coveralls and black rubber Wellington boots (Figure 3) were
worn by both the samplers and the student handlers. The wax markings were touched up
each morning of the study to ensure clear identification of pigs.

At 7:30 am on each day of the study, pigs were loaded onto a trailer and transported
0.3 km to the PALE facility and allowed to rest and adjust to the new flooring material
and penning (13.0 sq. meters) with their penmates for 3 hours prior to the experiment.
Pigs were off feed during the study and ad libitum water was made available in the

holding pens. Groups of 3 pigs, randomly selected from penmates, were moved into

45

smaller sampling pens at 3.6 sq. meters (Figure 4) 30 minutes prior to moving through
the circuit returning to the holding pens once sampling was complete. Of the 54 pigs that
moved through the circuit on day one, 35 pigs repeated the circuit on day two, however

no pigs repeated the circuit with the same group of three pigs.

Figure 5. Photograph of research assistant using a cOtton swab
to collect pig saliva, within the sampling pens.

 

46

Figure 6. Student handler, wearing coveralls, moving pigs through the
circuit using gate provided while observer records the pig’s behavior.

 

Behavior

Human behavior, pig behavior, and human-pig interaction was documented using
direct observation, focal sampling and continuous recording. The recording medium were
video and audio tapes. Circuit entry and exit points were standardized and time in the
circuit was recorded for the duration of each pig and the handler. Time was documented

using a stopwatch and verified against time recorded on videotape.

Human Behavior
Human behavior and human-pig interactions were documented using 4 black and

white 8 mm video cameras (Panasonic) fitted with a wide angle lens strategically placed

47

at each obstacle and at the entry and exit to the circuit. The cameras were positioned at a
height that allowed a fiontal view of the human in relation to the pig at both at the
beginning of the obstacle and while crossing the obstacle. The cameras were connected to
a time-lapse video recorder. Another hand-held cam-recorder was used to follow the
handlers, to increase recording of interaction and to record vocalization of the handler.
Behavioral observations
Audio and video tape recordings of pigs and humans were analyzed by focal
sampling and continuous recordings. Self-esteem scores of handlers were not known
when tapes were evaluated. Each human behavior element was recorded into a behavior
analysis computer. Recording of information was as follows:
a) video recordings were briefly reviewed to determine the amount of time the
stockperson required to complete the circuit.
b) video recordings were viewed repeatedly to gain familiarity, to determine the
nature of interactions observed and identify the pig receiving the behavioral element.
A bout criterion interval of 2 seconds was used to separate one interaction or
behavioral element from another.
c) observed interactions terms were defined (Table 1).
d) a focus pig was determined within the three pigs. The target pig was defined
as the pig which received at least 30 percent more behavioral interaction by the
handler, often times the most difficult to handle, than the other two pigs.

e) Check sheets were used to transcribe observations.

48

Table 1. Human behaviors categorized and defined.

 

 

 

 

 

 

 

 

 

 

 

 

Human Description
Behavior
VARIABLE
Bumping: Use of the body or gate to exert abrupt and short lasting pressure to
BUMP the pig, followed by release of pressure or the handler to step'back
slightly.
Pushing: Use of the body or gate to exert a constant pressure on the pig to
PUSH move pig in forward direction.
Blocking: Use of the body or a gate placed perpendicular to the pig, providing
BLOCK an immobilized barrier, to prevent pigs from retreating or escaping.
Gating: Use of the gate, by handlers, placed between the handler and the pigs
GATE to direct movement of the pig.
Parallel Gate is positioned parallel to the body of the pig.
Gating:
PARGTE
Slap: Contact or striking with the hand on the pig’s body. The action is
SLAP made by a full flexion fi‘om the elbow.
Slap head: Striking the pig’s head using the hand, gate or feet.
SLPHD
Vocalization: Verbal communication directed to the pigs; includes whistling,
HVOCAL talking, booting, pishing.
Pat: Contact with hand on the pig’s body. The action is made by a fill]
PAT flexion of the wrist.
Problem Cumulating behaviors by handlers such that the individual and
Solving: different variables are summed in the first 50 seconds of the
PROBSOLV HANTIME and the repeated behaviors are not included in the

 

calculation.

 

i) BOLD TYPE is the variable of human behavior used for statistical analysis

Reliability of behavioral Qta

Repeatability procedure: To ensure consistency in behavioral elements recorded the

following steps were taken.

a) hand-written recordings of number of bouts of interactions with each pig

during each task, and the nature of the interaction were carried out tape in a 12 hour

mode (12 fields/second).

 

49

b) hand-written recordings of number of bouts of physical interaction with each
pig during each task viewing tape was observed in in normal mode (60 fields/
seconds).

c) repeat recording of behavioral elements on check sheet viewing tapes in
normal mode until repeatability was greater than 85% in each elemental behavior.

d) intra-observer reliability was calculated using the Pearson product moment
correlation coefficient for a linear relationship on two data sets from five videos of
randomly selected handlers. This calculation was repeated for the three frequent
behavioral elements of pushing, gating, and slapping with coefficients of 0.923, 0.842

and 0.854 respectively, with the average of 87.3%.

Pig Behavior

Three “observers”, positioned inside the circuit, recorded pig behavior continuously
using an audio tape recorder. The categories were previously defined according to the
author’s definition and observers were trained using a video clip from a pilot study. The
following behavior categories were recorded (Table 2).

Information from the audio tapes were transferred to a computer program (Observer,
Noldus Information Technology). A hard copy of pig behavior was generated from the
program and used to determine the consistency of observers by comparing timing and
occurrence of pig behavior to videotapes. Vocalization could not be compared to non-
audio tapes. The average reliability of the observers recording behavioral events of each

pig, 92.6 %, was established by the mean of simply dividing the number of corrections

50
made by the video observer into the total number of behavioral elements listed on the

print out.

Table 2. Pig behaviors categorized and defined.

 

 

 

 

 

 

 

 

 

 

Pig Behavior Description
Variable
Balking: Resisting forward movement while standing firmly and leaning
BALK against the handler or gate.
Freeze: Standing motionless, independent of the presence of the
FRZE handler, while looking forward. Bars are pricked.
StOp: Pig has stopped motion (walking), may investigate
STOP surroundings
Rooting: Rubbing the rooting disc into and on the flooring surface while
ROOT in a standing position.
Lying down Lying or sitting passively lasting for more than five seconds
and without pig performing another behavior.
Nosing: Rubbing of the rooting disc against materials such as obstacles,
NOSE penning and human feet. Includes pigs standing still or
walking.
Turning around Pig turns around to change field of vision or to prior to moving
TURN in the opposite direction. or to
Escaping Pigs moves away from the obstacle, past the handler toward
ESC the begimring of the circuit
ESC:TURN The pig must turn in order to reposition itself to move in the

opposite direction and to move past the handler. Escape to turn
ratio is a calculation of the number of escapes by an individual
pig divided by the number of times the pig turned around.

 

 

 

 

 

 

 

 

Elirninative Urination and defecation

behavior

Vocalizations

1) Low grunt low tonal calls, associated with rooting or nosing an object
LOGRUN

2) High grunt high pitched tonal sounds, pig is generally excited.
HIGRUN

3) Squealing intense high pitch vocalization, pig is generally resisting
SQUEAL handling. In case of doubt, behavior is recorded under

HIGRUN.

 

i) Other categories include walking (WALK) and running (RUN) were not included in the
analysis because these variables were states whereas the other variables were counted as events.
ii) BOLD TYPE depicts the category of pig behavior used in statistical analysis

5 1
Cortisol Analysis

To obtain human saliva samples, students were asked to void their own saliva into a
Petri dish (Day 1) and a conical tube (Day 2) and to place the lid on that container. The
sample was then given back to the research assistant who placed the container on ice. The
human samples were taken concurrent to the pig saliva samples.

Pig saliva was collected from pigs using cotton buds (Q-tips, Johnson and Johnson)
on day one and using cotton dental rolls on day two. To retrieve the dental rolls fi'om the
pigs’ mouth, approximately 30 cm length of no wax dental floss (Johnson & Johnson)
was tied at the center of the (Figure 7). The pigs were allowed to chew the buds and rolls
for about a minute. The first saliva sample, the basal level, was taken in the pen prior to
moving pigs into the circuit. The second sample (time zero) was taken immediately on
completion of the circuit, and the third, fourth, and fifth samples were taken at 10
minutes, 20 minutes and 30 minutes past time zero respectively. Cotton buds and rolls
containing saliva were placed into 15 ml conical tubes, sealed and placed on ice until
moved into a -20° C freezer. The samples were later thawed and centrifuged at 2500 rpm
for 5 rrrinutes to collect saliva from the buds and rolls and to separate saliva from

particulate matter. Saliva samples were kept at -20° C until assay.

 

52

Figure 7. A polypropylene tube containing a cotton roll (left) and suspended with dental
floss. The second tube (right) contains 5 cotton buds tied together and suspended using
dental floss.

 

All saliva samples were thawed and centrifuged at 3000 g for 5 minutes. Saliva was
decanted into aliquots, frozen and kept at ~20°C until assay was processed. Salivary

cortisol was then measured by radioimmunoassay procedure using an assay for saliva

53
samples (Diagnostic Products Corporation Coat-A-Count Cortisol Determinations in

Saliva, September, 1992).

Human cortisol (HCORT) was determined by the mean concentration (nmol/l) of all
samples. Pig cortisol was calculated based on the area under the curve on percent increase
from basal level (CORTAUC) at four intervals, time zero, 10, 20, and 30 minutes post

completion of the circuit.
Validation Studies

Fluid retention of cotton rolls and cotton buds

Complete extraction of saliva collected from the cotton collection material was
important to ensure sufficient volume of saliva for RIA assay. To measure the fluid
retention of the cotton (dental) rolls and the cotton buds, twenty pp conical tubes
containing 2 ml of water were weighed. Ten cotton rolls and 10 bundles of 4 cotton
buds were immersed into the tubes allowing absorption of the water. The rolls and
buds were then suspended within the tubes, centrifuged at 3000 g for 5 minutes,
removed fi'om container and fluid retention was calculated against the final weight.
The cotton dental rolls retained 1.4% of the fluid, while the swabs retained 7.3 % fluid,

likely due to the paper material of the Q-tip stick.

Non-specific binding of cortisol in the cotton rolls and cotton buds
To determine the non-specific binding of cortisol to the material, 12 m1 of

standard cortisol solution (see dilution above) was divided into 3 sets (rolls, buds and

54

control) of 2 tubes. Two cOtton rolls and two bundles of cotton buds were immersed in
2 ml of standard cortisol solution . The two controls contained only solution. The rolls
and buds were suspended within 15 ml conical tubes (see Table 3) and all samples,
including controls, were centrifuged for 5 min at 3000 g. 200 pl of standard solution
were pipetted, in duplicate, into coat-A-count cortisol RIA kit (DPC) and the
manufacturer protocol was followed (Coat-A-Count cortisol determinations in saliva,
Diagnostics Products Corporation, September 4, 1992). The results of the assay (see
Table 3) depicts cortisol retention for the cotton buds and cotton rolls. Reduction of

standard concentration resulted in a higher coefficient of variation and linearity is lost.

Table 3. Measures of cortisol retention using cotton rolls, cotton buds and control

samples from tube 1 (T1) and tube 2 (T2).

 

 

 

 

 

Expected Rolls Buds Control

standard solution ‘ T1 T2 T1 T2 T1 T2
(nmol/l)

13.8 16.0 18.5 16.8 15.5 13.2 14.9

6.9 8.6 8.3 11.0 17.0 8.0 9.4

2.76 3.3 8.8 5.0 5.8 2.2 2.8

 

 

 

 

c) Dilution curve of cortisol samples (Figure 8).

100 ml of saliva was collected over 2 hours beginning at 6:00 am from five non-
experimental pigs and one human, when free cortisol is at peak levels (Baldwin and

Stephens, 1973; Cooper et al., 1989; Zanella, 1992). Saliva samples were serially

diluted using stripped saliva (species specific).

 

55

Charcoal double stripped saliva
60 ml of saliva was collected from 5 pigs and from 3 humans. Samples were
placed in flasks containing 2 g of sieved charcoal (Fischer C-1776 Carbon

Decolorizing Alkaline Norit-A) and mixed using a rotation mixer. Saliva was left

mixing overnight at 4 0C. On the following day the charcoal was separated from the
plasma by spinning down at 3000 g for 20 min. The human and pig saliva recovered
was mixed with 4 g of sieved charcoal and left mixing for a further period of 1 hour.
The solution was then spun at 3000 g for 20 min and the saliva collected was re-spun
at 20,000 g for 30 minutes. The saliva recovered was passed through filters and

standard solutions were prepared following the protocol described.

Interassay coefficient
The inter-assay coefficient of variation for controls (std/mean x 100) on thirteen
assays at 15.4 nmon concentration and 3.4 nmol/l concentration was 11.29 and 17.05
percent respectively.
The intra-assay coefficient of variation on 28 duplicate samples was 8.38 percent.
Intra-assay calculations were based on the following formula:
(2 (d/u x 100)2/2N)”2
where d = the difference between duplicate estimates

p. = the mean of the duplicate estimates
N = the number of duplicate samples

56

Figure 8. Serial dilution of pig and human salivary cortisol (nmol/l) based on the
percent of stock high cortisol saliva sample.

0 salivary cortisol concentration (nmol/l)

 

 

 

 

 

 

 

 

FIPig Saliva *Human Saliva ]
25 ________________________________________
20 ----- — ———————————————————————————————
15 ————————————— ~ ------------------------
1° ________________ / _____________
5 r/i/ ““““““““““““““““
ILL/f
0 L ——~——-— Q/

 

0 12.5 25 Si) 100
percent of original dilution of high cortisol concentration saliva

Spiked saliva samples (stock cortisol solution)

Hydrocortisone (Sigma, N0. H-4001) was kept as a stock A = lug/ml solution in
EtOH. Stock A was diluted 1 in 5 (stock B) which had 200 ng/ ml.

Stock A and B were pipetted into pp conical tubes. The tubes were dried down
under N2, The samples were vortexed and incubated at room temperature for 30
minutes. Samples were aliquoted in eppendorf test tubes.

Standard cortisol solutions, quality control (QC), were as follows:

QC1= 13.8 nmon (30ul A + 6ml of stripped saliva)

QC2= 6.90 nmon (15ul A + 6ml of stripped saliva)

57
QC3= 2.76 nmon (30ul B + 6ml of stripped saliva

QC4= 1.38 nmon ( 15 ul B + 61111 of stripped saliva)

Basal cortisol

To establish a salivary cortisol depletion curve and to validate basal levels of
salivary cortisol levels and control responses to handling in juvenile pigs, saliva
samples were collected using cotton buds. Five barrow penmates ranging from 150 to
200 pounds were selected and identified using a marking stick crayon and sampled on

three consecutive days at approximately 4:00 PM.

Inter-pig variation of salivary cortisol.

On day one pigs were mock sampled for salivary cortisol by taking three saliva
samples within a 1 minute period. On day two, basal levels were determined by
taking three saliva samples within a maximum 2 minute time period. The inter assay
coefficient of variation (std/mean X100) of saliva samples taken from 5 pigs within
one minute are 26.6%, 47.0%, 8.4%, 41.7%, 0% (Table 4 )

Table4. Basal salivary cortisol (nmol/l) determined from 5 different pigs and three
samples collected within a two minutes time period.

 

 

 

 

 

 

 

 

 

 

Cortisol Pig 1 Pig2 Pig 3 Pig 4 Pig 5
(nmol/l)
Mean 4.33 5.33 13.67 7.33 4.0
Std 1.15 2.51 1.16 3.06 0.0

 

58
Determining Sampling Intervals

To establish a salivary cortisol depletion curve (Figure 9) and to validate basal
salivary cortisol levels and control responses to handling in juvenile pigs, saliva samples
were collected fi'om five barrows. Samples were taken at four minute intervals beginning
12 minutes prior to moving through a circuit. At time zero, the pigs were moved out of
their pens, into the aisle, along the aisle, over a ramp, across a black plastic bag and
returned to their pens. The time to complete the circuit was recorded and another saliva
sample was taken. The sampling continued every four minutes until 40 minutes post
circuit completion. Samples were placed on ice immediately post collection and stored at
-20°C until analysis using direct radioimmunoassay (DPC). The peak cortisol
concentrations results are depicted in Figure 9.

Figure 9. Mean salivary cortisol of pigs at 4 minute intervals from 12 minutes prior to
circuit to 40 minutes post completion of the circuit.

Mean salivary cortisol (nmolli) of 5 pigs at 4 minute intervals pre (0) and post (0') circuit

20

 

 

[I +l-SEM —pre circuit e-post circuit |

,5 TTTTT T

10 ll
1 1 1
54441.. .

~12-8-4 0 0'4 81216202428323640
sampling time in four minute intervals

 

 

salivary cortisol (nmolli)

 

 

 

 

59
Statistical Analyses

PROC GLM, PROC MIXED and PROC CORR were used from SAS software
library SAS INSTITUTE Inc. SAS/STAT Guide for Personal Computers, (Version 11.6
Cary, North Carolina: SAS Institute Inc., 1994). Descriptive analyses were computed for
range, mean and standard deviation for dependent continuous variables whereas estimated
coefficient, standard error of the coefficient and P-values were constructed for categorical
data, and dependent and independent continuous variable data. Non-normality was
determined by using normal probability plots. Human behavior and pig behavior were
separately correlated using a Pearson’s Product Correlation analysis with both All Pigs
data and the data set restricted to the Focus Pig Only. This analysis was used to determine
associations and discern similar behavioral elements. Regression analysis for dependent
variable human cortisol CORTAUC was conducted using a 2 level PROC MIXED model
for independent variables, pig and human behavior, with a random effect for the handler.
A 2 sample Students t test was used to compare cortisol measure of pigs repeating the

circuit. Significance was established at P _<_ 0.05.

Definition: All Pigs and Focus Pig

During the study it was noted that while moving a group of pigs, handlers often dealt
with one pig more than the other two. This particular pig, usually resistant to moving
through the circuit, became the focus of the handler. It was considered that congruent

analysis of the interaction between the handler and this pig would provide a direct

60

breakdown of the association with human behavior and pig physiology and behavior. To
investigate the nature of interactions of handler to one pig, in addition to all pigs, the data
was analyzed using a congruent, restricted data set (Focus Pig, =23) and the complete

data (All Pigs, n=32).

The criteria of the Focus Pig include:
1) There is a maximum of 1 Focus Pig per handler.
2) Behavioral elements by the handler toward the Focus Pig exceed behavioral
elements toward the other pigs by at least 30 percent.
3) HANTIME must exceed one minute.
4) There is a minimrun of 15 behavioral elements by the handler toward the Focus

Pig.

Dependent Variable Analysis

HANTIME Analysis

The handler’s time in the circuit is considered the time taken to move pigs in the
circuit. Pigs tend to move in a group and it is expected that pig-pig interactions may
influence the time in the circuit. Since the last pig to exit the circuit preceded the handler,
the handler time encompassed time in the circuit for three pigs and a handler. Handler
time analysis (HANTIME) was conducted using a general linear regression bivariate

model for the average of three pigs.

61
Seven handlers did not complete the circuit with all three pigs. Five of the handlers

discontinued moving pigs due to frustration or exhaustion. Of the other two groups, one
pig jumped out of the circuit and in the second group a pig showing typical signs of

respiratory distress was removed.

HCORT and CORTA UC Analysis

Measuring Human Cortisol (HCORT)

During the two days of the study, student handlers (n=32) provided 160 saliva
samples, of which 102 samples were measurable using Direct RIA of cortisol. Since 47 of
the missing 58 measures were on day one, the most likely cause is the type of container
used for saliva collection. The containers used by handlers to provide a sample a 2 ml
petri dish on day one and a 12 ml conical tube on day two. It is considered that the
shallow and smaller volume of the dish may have limited sample volume provided by the
handlers compared to the conical tubes.

Further data analysis revealed that a maximum of 19 handlers had submitted
measurable samples within the same interval (i.e. post to 10 minutes or 10 to 20 minutes).
Therefore, it was decided to take the mean of measurable samples (minimum of two
measures per handler) to determine a human cortisol concentration per handler (n=28).
This mean value is reasonable for human cortisol measures since, unlike the pigs that do
not know when the stressful episode with be, a human subject anticipates moving pigs
and therefore basal levels may be higher than post handling. In addition, humans tend to
have a more stable circadian rhythm (Guyton, 1991 ), without the episodic spikes reported

in juvenile pigs (Ruis et a1, 1997).

62

Regression analysis was conducted using a general linear model for categorical and
continuous independent variables.

Measuring Pig Cortisol Levels (CORTAUC)

To establish the change in concentration levels of cortisol for an individual pig over
time, area under the curve (% change'min), a statistically valid method (Matthews et al.,
1990) was identified and calculated for each pig. Since the time in the circuit varied
between handlers, HANTIME was excluded from the calculation. The time factor was
standardized to 30 minutes (x-axis) to included 4 serial measures of cortisol (see Figure
11b): immediately post HANTIME (time zero) and 10, 20, and 30 minutes later. For the
y-axis, salivary cortisol concentration levels (nmon) were adjusted for individual pig
basal levels by calculating the serial measures as a percent difference in cortisol
concentration from the basal salivary cortisol concentration (see Figure 11b).

Regression analysis was conducted using a PROC MIXED 2 level model including a
random effect variable for handler for continuous independent variables. ANOVA

calculations were used for categorical variables.

Independent Variable Analysis

The time in the circuit varied between handlers and subsequently frequency of

behavioral elements increased as time increased. Therefore human and pig behavior is

determined in rates, calculated based on frequency of behavior per time unit.

Figure

63

10a, 10b. Two separate line graphs over the four 10 minute sampling
intervals for a group of three pigs moved by handler. The top figure demonstrates cortisol
concentration (nmol/l) without adjustment for basal levels. The bottom graph
demonstrates cortisol concentration with adjustment for basal levels at percent increase

over basal cortisol concentrations

Handler 424

salivary cortisol concentration (nmolli)

 

150

 

 

F

I s—pig 23 +pig 18 +pig 21 I

 

 

 

10 20 30
sample time (minutes) post circuit

Handler 424

% increase of basal salivary cortisol concentration

 

 

 

 

 

 

 

sampling time (minutes) post circuit

RESULTS

Study Population

Descriptive Results of Handler Characteristics

The self esteem scale scores for the 115 survey participants, 74 females and 29
males, ranged from 1.0 to 5.0 (mean=4.09; SD=0.754). Selected subjects, 20 females and
13 males, were based on high and low self-esteem scores and gender and stratified based
on lab times. Esteem scores ranged fiom 1.0 to 5.0 (n=32; mean=4.009; SD=1.109).
Scores of the low self esteem group ranged from 1.0 to 3.8 (n=18; mean=2.987;
SD=0.822) and scores of the high self esteem group ranged fiom 4.6 to 5.0 (n=l4;

mean=4.859; SD=0.128).

Descriptive Results of Handler Behavior
The descriptive analysis of human behavior is shown in Table 5. The definitions of

these behavior variables are listed on page 45.

65

Table 5. Descriptive statistics of variables of human behavior for complete data set.

 

 

Continuous N* Mean S D Minimum Maximum
Variable

GATE 32 1.32 0.022 0 0.089
BLOCK 32 0.017 0.02 0 0.137
PAT 32 0.010 0.02 0 0.125
BUMP 32 0.017 0.028 0 0.187
VOCALIZE 32 0.02 0.069 0 0.333
PUSH 32 0.03 0.041 0 0.272
SLAP 32 0.038 0.07 0 0.373
SLPHD 32 0.004 0.01 0 0.061
PARGTE 32 0.0003 0.0017 0 0.011
PROBSOLV" 32 5.5 1.43 2 10.0

 

I"Denotes the mean values of handler behavior toward the group of three pigs.
"Denotes cumulative sum of different variables in the first 50 seconds of HANTIME

ANO VA of Handler Characteristics

Effects of Self Esteem on Handler Behavior

When handler self esteem scores were compared to frequency of handler behaviors in
both All Pigs and Focus Pig Only data bases (Table 6), rate of slapping SLAP (P=0.06)
in the restricted focus pig data set was higher in handlers who scored lower on self
esteem. Conversely, those with lower self esteem scores were less likely to block

(BLOCK) the focus pig (P=0.09).

66

Effects Of Gender On Handler Behavior

There was little influence of gender on human behavior, with one exception; male
handlers in this study showed an increased tendency (PUSH, P=0.08) of pushing the

focus pig when compared to the female handlers (Table 7).

Table 6: Mean values and significance based on ANOVA computation of self esteem and
rate of human behavior of the All Pigs data and the data set restricted to Focus Pig.

 

 

Data Set All Pigs ‘ Focus Pig "
Continuous Low High low high
Variable (n=14) (n=18) P value (n=9) (n=14) P value
GATE 1.51 1.21 0.39 2.505 1.75 0.39
BLOCK 0.74 1.19 0.13 0.88 1.97 0.09
PAT 0.28 0.83 0.21 0.26 1.20 0.31
BUMP 0.69 1.23 0.17 1.16 2.61 0.17

HVOCAL 0.81 1.81 0.51 0.00 0.37 0.19

PUSH 2.15 1.50 0.24 5.16 3.48 0.29
SLAP 2.90 1.76 0.33 7.37 2.37 0.06
SLPHD 0.35 0.20 0.36 0.23 0.41 0.52

PARGTE 0.00 0.034 0.27 0.00 0.04 0.39

 

 

PROBSOLV 4.87 6.00 0.06 4.88 5.78 0.20

 

a) n=32 handlers; b) n = 23 handlers
I”Denotes cumulative mm of different variables in the first 50 seconds of HANTIME

67

Table 7: Mean values and significance based on AN OVA computation of gender and
rate of human behavior of the All Pigs data and the data set restricted to Focus Pig Only.

 

 

Data Set All Pigs ‘ Focus Pig Only'
Continuous Male Female P value Male Female P value
Variable (n=12) (n=20) (n=9) (n=14)
GATE 1.29 1.37 0.83 2.43 1.79 0.24
BLOCK 0.71 1.16 0.14 1.23 1.74 0.54
PAT 0.85 0.43 0.36 0.62 0.96 0.33
BUMP 0.76 1.13 0.36 1.85 2.16 0.88

HVOCAL 0.74 1.75 0.50 0.14 0.27 0.78

PUSH 2.33 1.46 0.12 5.51 3.21 0.08
SLAP 2.26 2.26 0.99 4.17 4.43 0.90
SLPHD 0.16 0.33 0.30 4.32 0.23 0.19
PARGTE 0.00 0.03 0.34 0.02 0.00 0.34

PROBSOLV 5.25 5.65 0.52 5.33 4.88 0.81

 

 

 

a) n=32 handlers; b) n = 23 handlers
I”Denotes cumulative sum of different variables in the first 50 seconds of HANTIME

Human Salivary Cortisol

AN OVA for the dependent variable human cortisol (HCORT, n=28) was conducted
using a general linear model with independent variables regarding pig and human
behavior.

Categorical Variables with the Dependent Variable Human Cortisol:

AN OVA of HCORT using the independent categorical variables are presented in

68
Table 8. The major finding was the strong positive association of high cortisol found in

males handling the focus pig (P=0.001).

Table 8: AN OVA computation of mean human cortisol (nmol/l) levels and categorical
variables using All Pig data and Focus Pig only data set.

 

 

 

Data Set All gigs ‘ Focus Pig Only”
Categorical N HCORT SEM :I: P value N HCORT SEM P
Variable mean mean i value
ESTEEM
Low 13 10.2 0.41 0.30 9 9.75 1.67 0.43
High 15 8.36 0.27 12 8.05 1.32
RPTS
no 46 9.94 0.56 O. 16 9 9.81 1.96 0.40
once 38 8.37 0.61 12 8.01 1.25
HGENDER
Male 11 11.32 0.41 0.06 9 12.07 1.55 0.001
Female 17 7.89 0.27 12 6.32 0.89
PGENDER I
Male 26 8.61 0.81 0.61 5 7.52 1.32 0.51
Female 70 9.47 0.58 16 9.17 1.30

 

 

 

(a) n=67; (b) n=21

Pig Salivary Cortisol

Descriptive Analysis

The minimum, maximum, mean and standard deviation CORTAUC was min; 783.33
% change°minute, max; 21675.0 % change'minute, mean; 5062.0 % change'minute and
SD; 3913.0 % change°minute.

Bivariate Analysis: Effect of Class Variables on Salivgy Cortisol

Results of AN OVA for the COR TA UC, (n=85) was conducted using a general linear

mode with categorical variables (Table 9). The major finding was the significantly higher

69

CORTAUC (P=0.05) in the 37 pigs that had not repeated the circuit. This was confirmed

using a Student’s t-test comparing cortisol levels from the 31 pigs repeating the circuit to

the cortisol levels determined from day one and day two (P=0.02).

Table 9. ANOVA analysis with CORTAUC (% change nmol/l'min) and
categorical variables for All Pigs data set and restricted data set for Focus Pigs Only.

 

 

 

 

 

Data Set All Pigs ‘ Focus Pig Only”
Categorical N CORTAUC SEM P N CORTAUC SEM P
Variable mean i value mean i value
ESTEEM
Low 15 5141.90 632.81 0.72 9 6623.89 1314.10 0.36
High 17 4767.01 559.30 14 5105.60 749.00
RPTS
no 51 5598.00 546.62 0.13 11 7111.67 1071.02 0.02
once 37 4300.91 633 .21 12 4405.42 732.65
HGENDER
male 12 5198.86 786.87 0.59 9 5116.48 548.27 0.47
female 20 4770.32 477.56 14 6074.64 1061.77
PGENDER
male 25 4652.60 619.13 0.52 6 6777.5 1953.14 0.38
female 63 521 1.69 529.83 17 5319.31 650.73
a)n=85;b)n=23

Time in the Circuit

Descriptive Statistics

The variable HANTIME is representative of the handler time in the circuit. Since the

handler does not precede the pigs they were moving and because the correlation between

individual PIGTIME and HANTIME was high (P=0.000), HANTIME was assigned as

the time of completion for both All Pigs and Focus Pigs data set.

70

The minimum HANTIME was 0.80 minutes and the maximum was 13.75. The mean

HANTIME was 4.48 minutes with a standard deviation of 3.71 minute.
Association of Categorical Variables with Time in the Circuit:

Results of regression analysis of the dependent variable HANTIME with categorical
variables for ESTEEM, HGENDER, and RPTS are presented in Table 10.

Esteem MGCM

Handlers with high self-esteem were not significantly different with the time required
to move All Pigs (P=0.60) and Focus Pigs Only (P=0.70) from those handlers scoring
lower in self esteem. In addition, male handlers were not significantly (All Pig; P=0.80;
Focus Pig Only; P=0.47) faster moving pigs through the circuit than were the female
handlers.

Rgpeat Pigs

All Pigs data results reveal that pigs which repeated the circuit on day two (RPTS)
were not different (P=0.60) from pigs moving through the circuit for the first time.
Analysis using the Focus Pig Only data set demonstrates that pigs repeating the circuit

have a tendency of less time in the circuit (P=0.10).

71

Table 10. AN OVA computation with mean and standard error of HANTIME (minutes)
and categorical variables ESTEEM, REPEATS, Human gender (HGENDER), and Pig
gender (PGENDER) variables.

 

 

Data Set All Pigs ‘ Focus Pig Only "
Categorical N HANTIME SEM P N HANTIME SEM P
Variable mean :i: value mean i value
ESTEEM
Low 15 4.88 1.16 0.60 9 4.75 1.31 0.49
High 17 4.17 0.78 14 4.72 0.89
REPEATS
No 58 4.90 0.79 0.12 11 5.51 1.19 0.05
Once 38 3.84 0.45 12 4.02 0.86
HGENDER
Male 12 4.25 0.73 0.80 9 4.05 0.78 0.47
Female 20 4.61 0.97 14 5.16 1.09
PGENDER
Male 26 4.15 0.71 0.52 6 3.35 0.98 0.58
Female 70 4.60 0.45 17 5.21 0.90

 

 

 

a)n=32;b)n=23

Handler Behavior

Correlation Amoung Human Behaviors:

As presented in Table 11, correlations were determined among the physiological
stress of handlers (HCORT), time required to move pigs (HANTIME), and behavior and
handler strategies. Note: Correlation and P values are represented in Table 11 for the All
Pigs data set, while correlation and P values will be included in the text for the focus pig
data set). HCORT was inversely associated with HANTIME (r= -0.37, P=0.05). The
variable Problem Solve (PROBSOLV), was moderately positively correlated with
HCORT (r=0.43) and negatively correlated with HANTIME (r= -O.37). Human behaviors
BLOCK (r=0.37, P=0.04) and HVOCAL (r=0.34, P=0.05) were also correlated with

PROBSOLV. Analysis using both data sets showed negative association between

72
directive behavior such as GATE with PROBSOLV (F -0.47, P=0.007; r= -0.43,

P=0.04; All Pigs and Focus Pig respectively). PARGTE, an ineffective position of
holding the gate while moving pigs, was slightly positively associated with HANTIME
(r=0.303; r=0.440, P=0.10; P=0.10, All Pigs and Focus Pig data sets respectively). There
was a negative correlation of HCORT with HANTIME (r= -0.37, P=0.05) and
corroborated in the Focus Pig sample (r= -0.42, P=0.06).

The strongest correlation among handler behaviors is HVOCAL and BLOCK
(r=0.73, P=0.000). Review of the videotapes reveal that blocking is used by the handler
to prevent the pig from retreating back toward the start of the circuit or at least opposite
of the obstacle, and if successfirl prevents the pig(s) from escaping. Furthermore, using
the Focus Pig set, there is a significant association between HVOCAL and SLPHD
(r=0.44, P=0.03) and PUSH and GATE (r=0.42, P=0.05).

Table 11. Correlation analysis of HANTIME, PROBSOLV and RTHVOCAL with rates
of human behavior using the All Pigs data set.

 

 

 

 

Continuous HANTIME PROBSOLV RTHVOCAL

Variable
All Pigs data r P value r P value R P value
GATE -0.187 0.31 -0.467 0.007 -0.162 0.37
BLOCK -0.220 0.23 0.372 0.04 0.729 0.0001
BUMP -0.294 0.10 0.226 0.21 0.065 0.72
HVOCAL -0.306 0.09 0.338 0.05 1.00 0.00
PUSH 0.100 0.59 -0.014 0.45 0.070 0.70
SLAP -0.292 0.10 0.144 0.43 0.196 0.28
SLPHD 0.223 0.22 0.271 0.13 0.081 0.66
PARGTE 0.303 0.09 0.278 0.12 -0.075 0.68
PAT -0.1 12 0.54 0.207 0.25 0.1 14 0.53
PROBSOLV -0.3 88 0.03 1 .00 0.00 0.338 0.05
HCORT -0.373** 0.05 0.426“ 0.02 0.263 0.17

 

 

 

71L PIGS, n=32; "n=23; r denotes correlation value

73

Effects of Handler Behavior on Human Salivary Cortisol

As presented in Table 12, behavior that was associated with a significant increase in
HCORT was human behaviors SLAP (P=0.05) and PROBSOLV (P=0.0001) and pig
behavior BKWD (P=0.048).
Table 12. Regression analysis of mean and standard error of human cortisol HCORT

(nmol/l) and rate of handler behavior for All Pigs data and the restricted Focus Pig Only
data set.

 

 

Data Set All Pigs ‘ Focus Pig Only'

Variable Variable

Human Estimate :tSE P value Human Estimate :1: SE P
Behavior ' Behaviorb value
BLOCK -20.5 63 .94 0.75 BLOCK -67.7 36.7 0.81
PAT -15.8 42.8 0.71 PAT -49.7 33.9 0.16
SLAP 0.51 0.25 0.05 SLAP 0.20 0.19 0.29
PROBSOLV 1 .14 0.47 0.0001 PROBSOLV 0.97 0.62 0.13

 

 

 

 

' denotes All Pigs, n=15; ° denotes Focus Pig Only; bold type denotes P5005

The Effect of Human Behavior on Pig Salivary Cortisol

As presented in Table 13, a tendency was shown for association between the human
behavior, patting (PAT) and increased pig salivary cortisol (P=0.10). This is supported in
the Focus Pig Only analysis which reveals a significant increase in cortisol concentrations
with a higher rate of patting (P=0.03). In contrast, when handlers increased bumping,
(BUMP), while handling the target pig, there was a significant reduction in CORTAUC

levels (P=0.05).

74

The Effect Human Behavior on Time in the Circuit (Table 14)

Although most human behavior had no significant effect on HANTIME, handlers
using a variety of behavioral elements in the first 50 seconds of circuit time
(PROBSOLV) significantly reduced the time in the circuit (P=0.03). Other behaviors
bumping, slapping and vocalization, at best, demonstrated a tendency (P5010) for less
time in the circuit while an increase in rate of parallel gating was mildly associated to an
increase of time in the circuit (P=0.09). Confirming that finding, the association of

parallel gating (PARGTE) using Focus Pigs Only data also showed a tendency toward

increased time in the circuit (P=0.10).

Table 13. Regression analysis with dependent variable CORTAUC (percent increase of
cortisol by time (minute)) and human behavior for All Pigs and the restricted Focus Pig

 

 

Only data sets.
All pigs a Focus Pigs Only b
Variable Estimate i SE P value Estimate :1: SE P value
Human Behavior
GATE - 195.74 315.93 0.54 - 234.23 425.48 0.59
BLOCK - 255.97 309.94 0.41 - 438.21 441.97 0.33
PAT 534.19 325.57 0.10 847.50 367.86 0.032
BUMP - 272.18 238.87 0.26 - 492.14 238.87 0.05
HVOCAL - 90.17 100.32 0.37 - 1262.57 947.28 0.20
PUSH 135.37 165.50 0.42 - 102.95 210.19 0.63
SLAP 14.53 101.27 0.89 82.85 125.79 0.52
SLPHD 89.80 658.71 0.89 39.59 822.46 0.97
PARGTE 23.87 4115.2 0.99 992.00 4946.5 0.84

 

 

 

75

 

 

 

PROBSOLV 220.38 245.75 0.37 270.74 422.58 0.53

 

a) n= 85 pigs; b) n=23 pigs
Table 14. Regression analysis of HANTIME estimated coefficient (:I: SE) and different
rates of All Pigs and Focus Pigs Only handler behavior.

 

 

 

 

 

Data Set All pigs‘ Focus Pig Only"
Variable Estimate :I:SE P value Estimate i SE P value
Handler Behavior

GATE 2603.0 2500.3 0.30 17.8 1672.2 0.99

BLOCK -3590.7 2907.4 0.23 - 49.1 1744.7 0.98

PAT -1219.0 1981.1 0.54 189.6 1629.2 0.90

BUMP - 3678.5 2183.4 0.10 - 847.9 1009.5 0.41

HVOCAL - 995.4 563.9 0.09 - 2771.4 3808.4 0.47

PARGTE 46035.1 26398.8 0.09 30412.5 18084.3 0.1 1

PUSH 864.0 1584.0 0.59 72.3 820.0 0.93

SLAP - 1211.4 723.3 0.10 - 456.9 493.1 0.36

SLPHD 6644.1 5303.4 0.22 - 2533.2 3194.6 0.44

PROBSOLV - 51.756 22.46 0.03 - 30.8 27.4 0.27
Pig Behavior

Table 15. Descriptive analysis of pig behavior variables for the All Pig data set.

 

 

Variable NM Mean S D Minimum Maximum
TURN 96 0.03 0.025 0 0.13
BKWD 96 0.014 0.012 0 0.035
FREEZE 96 0.003 0.006 0 0.04
BALK 96 0.008 0.016 0 0.113
ESCAPE 96 0.005 0.009 0 0.041
ROOT 96 0.01 0.014 0 0.067
NOSE 96 0.02 0.02 0 0.09
LOGRUN 96 0.02 0.027 0 0.12
HIGRUN 96 0.007 0.01 0 0.07

 

 

76

 

SQUEAL 96 0.02 0.038 0 0.18
ESC:TURN 67 0.202 0.042 0 0.83

 

 

"Denotes pig specific values of pig behavior

Correlation among Pig Behaviors

Using data (Table 16) the Pearson’s correlation analysis determined a significant
positive correlation (r=0.374, P=0.000) between the avoidance behaviors ESC and
TURN. Significant and mild correlation of ESC with pig vocalizations were LOGRUN
(r=0.20), HIGRUN (r=0.30) and SQUEAL (r=0.26) while TURN was significant and
moderately correlated to SQUEAL (r=0.34). Explorative behavior NOSE was highly
significant, yet a low negative correlation to both RTESC (r= -0.25, P=0.01) and TURN
(r= -0.20, P=0.05). Significantly positive correlated with TURN were ROOT (r=0.20)
and LOGRUN (r=0.25).

The pig measure ESC:TURN ratio was, on average, 3.4 turns to 1 escape or an
ESC:TURN ratio of 0.29. The ESC:TURN measure was moderately correlated to
vocalizations HIGRUN (r=0.40) and SQUEAL (r=0.24).

Vocalizations LOGRUN, HIGRUN and SQUEAL were investigated for possible
correlation with other pig behaviors. In addition to strong associations with TURN AND
ESC, there was substantial correlation among pig vocalizations of LOGRUN with
HIGRUN (0.37) and SQUEAL with HIGRUN (0.24). Inspectorial behavior such as
ROOT and FRZE (r=0.20; r=0.24, respectively) were associated with LOGRUN.

Using restricted Focus Pig Only data set, correlation analysis of pig behavior with
measures of pig cortisol (CORTAUC) revealed significant association with vocalization
HIGRUN (r=0.49, P=0.02) and a tendency toward LOGRUN (r=0.35, P=0.10). Similar

to ALL PIGS analysis, TURN is strongly associated with RTESC (0.52, P=0.01) and

LOGRUN (r=0.50, P=0.01) and vocalizations HIGHRUN is strongly associated to

LOGRUN (0.54, P=0.008).

Table 16. Correlation between pig behavior variables escape, tum, low grunts,

high grunts, and squeal to other rates of pig behavior for ALL PIGS data set

(correlation; P value).

 

 

Variables
Human ESC TURN LOGRUN HIGRUN SQUEAL
Behavior
ESC 1.0; 0.00 0.374; 0.0002 0.204; 0.05 0.304; 0.003 0.260; 0.009
TURN 0.374; 0.0002 1.00; 0.00 0.251; 0.01 0.120; 0.25 0.333, 0.001
ESC:TURN 0.824; 0.0001 0.036; 0.77 0.174; 0.16 0.399; 0.0008 0.240; 0.05
BALK 0.171; 0.10 -0.053; 0.61 0.204; 0.21 -0.03; 0.72 0.040; 0.67
ROOT 0.132; 0.20 0.200; 0.05 0.172; 0.09 0.100; 0.33 -0.135; 0.19
BKWD -0.120; 0.24 0.077; 0.46 0.068; 0.51 0.014; 0.89 0.108; 0.29
FRZE 0.014; 0.89 0.076; 0.46 0.242; 0.02 -0. 129; 0.21 0.031; 0.76
NOSE -0.249; 0.01 -0.200; 0.05 0.076; 0.46 0.081; 0.43 0.093; 0.37
LOGRUN 0.204; 0.05 0.251; 0.01 1.0; 0.00 0.370; 0.0002 0.164; 0.1 1
HIGRUN 0.305; 0.003 0.120; 0.25 0.370; 0.0002 1.00; 0.00 0.244; 0.02
SQUEAL 0.264; 0.009 0.338; 0.0009 0.164; 0.1 1 0.244; 0.02 1.00; 0.00

 

n= 96; bold type denotes P3005

Regression Analysis of Pig Behavior

Human Saliva (Table 17)

Pig Behavior, ESC:TURN, was inversely near significance (P=0.06) to human

cortisol concentrations. Interestingly, pig behaviors associated with reduced HCORT

included other avoidance behavior TURN (P=0.036) and ESC (P=0.016) as well as

 

78
investigatory behavior ROOT (P=0.004). Analysis from Focus Pig Only data revealed no

significant association to HCORT.

Table 17. Regression analysis of mean cortisol HCORT (nmon) and rate of pig behavior
for All Pigs data and the restricted Focus Pig data set.

 

 

Data Set All Pigs ' Focus Pig Only "
Independent Variable

Pig Behavior‘ Estimate iSE P value Estimate 3: SE P value
ESC -296.1 114.8 0.02 -117.5 0.19 0.19
TURN - 104.1 47.2 0.04 -34.4 33.1 0.31
ESCTURN - 3.9 2.0 0.06 - 3.8 2.9 0.18
BALK -43.3 88.1 0.63 263.36 153.4 0.10
ROOT -240.4 77.0 0.004 -130.16 67.2 0.07
LOGRUN -100.4 55.0 0.08 -28.4 40.7 0.49
HIGRUN -l30.69 111.4 0.25 6.98 41.9 0.83
SQUEAL 6.82 47.5 0.89 41.0 22.9 0.08

 

 

 

8) denotes All Pigs, n=67; b) denotes Focus Pig Only; bold type denotes P5005

Pig Salivary Cortisol
Pig vocalization HIGRUN, was associated with a tendency (P=0.075) using the All
Pigs data and a significant increase (P=0.019) in CORTAUC levels with the Focus Pigs

Only data set.

Time in the Circuit (Table 18)
The variable HANTIME was significantly associated with independent variables for

pig behavior. Avoidance behavior of pigs, such as turning and escaping, (TURN and

79
ESCAPE) significantly increased the time in the circuit (P=0.005, for both behavior).

Focus pig data supports such behavior as significantly highly associated with increased
time in the circuit (TURN, P=0.002, and ESC, P=0.008). A ratio of escape to turn was
significantly associated (ESC:TURN, P=0.000) with an increase in HANTIME

Pig vocalization, low grunting and high grunting, (LOGRUN and HIGRUN) were
significantly associated with longer time in the circuit (P=0.000). Motion behavior in
pigs such as walking (WALK, P=0.002) was significantly associated with less time in the
circuit.

While rooting (ROOT) was significantly associated (P=0.01) with an increase of
HANTIME, another investigatory behavior, nosing (NOSE), was significantly associated
(P=0.02) with a decrease in HANTIME.

Table 18. Regression analysis of HANTIME estimated coefficient (t SE) and using All
Pigs data and restricted Focus Pig Only data set.

 

 

 

Data set All Pigs Focus Pig Only

Independent

Variable Estimate iSE P value Estimate :1: SE P value
Pig Behavior‘
TURN 1.65 0.54 0.005 1.23 0.54 0.0024
BKWD - 0.52 1.59 0.75 - 0.24 1.16 0.83
FRZE 3.99 2.54 0.13 - 0.64 1.71 0.71
BALK - 1.31 1.10 0.24 - 0.99 1.98 0.62
ESC 4.36 1.43 0.005 2.91 0.99 0.008
ROOT 2.60 0.97 0.01 1.33 0.86 0.13
NOSE - 1.57 0.62 0.02 - 0.42 0.86 0.63
LOGRUN 2.10 0.57 0.0009 0.65 0.48 0.19
HIGRUN 4.18 1.19 0.001 0.87 0.52 0.11
SQUEAL 0.49 0.47 0.30 - 0.04 0.31 0.91
ESC:TURN 0.87 0.52 0.0007 286.3 166.1 0.1 1

 

 

 

DISCUSSION

The discussion is presented in subsections that allow methodical review of findings
based on the three purposes of this study. The first aim of this study was to provide
information, based on characteristics of the study population, on the nature of interactions
which humans are likely to perform when handling pigs. Secondly, this study attempted
to determine the success of different handler strategies by observing the interrelationship
of behavioral and physiological response of pigs. The last objective was to provide
scoring or a scale, derived from the present study, to deduce methods of selection and

training of stockpeople.

The Study Population:

Human Characteristics and the Interactions Used by Handlers

Self-esteem

In general, the self-esteem score used in this study was not a strong variable in
predicting behaviors used by handlers when interacting with pigs with two exceptions.

First, those handlers who scored lower in self-esteem while handling the focus pigs were

80

81
mildly associated with an aggressive behavior of slapping. Hemsworth et al., (1989)

points out that behavior such as slapping and kicking, regardless of infliction, was
considered aversive by pigs. Slapping, by humans, is generally considered an aggressive
behavior (Crowell, 1986) and may be a result of frustration experienced by those of a
lower self-esteem while moving the often non-compliant focus pig. At the other end of
esteem score, the restricted focus pig data set also revealed an association between higher
self-esteem and blocking behavior. Those of higher self-esteem may be less likely to
revert to aggressive behavior or perhaps blocking, whether learned or part of the problem
solving behavior repertoire, will thwart fi'ustrating events such as escape behavior by
pigs. Thus, frustration and aggressive behavior such as slapping are reduced.

The fact that a global personality scale was not highly predictive of individual human
behavior is not surprising. There was a shift toward the higher self-esteem scores that
may be explained by the fact that respondents may misreport their behavior and attitudes
in a positive bias on self reports, especially in cases of socially desirable behaviors such
as self-esteem (Ajzen, 1988). A review of the personality literature reveals that
correlations between characteristics and behaviors relevant to those characteristics are
often nonsignificant (Ajzen, 1988). According to Ajzen, personality is derived flour a
genetic component diverged with the individual’s experiences, creating a complex
human. This complexity makes it difficult to predict single or overt human behaviors
based on a questionnaire assessing personality traits. Rather, predictions of behavioral
tendencies are made based on the average person’s experience or past behavior in a

similar situation. These behavioral observations are referred to as base rate data

82
(Baughman and Welsh, 1962; Ajzen, 1988). Utilization of this data allows us to better

predict and measure human behavior

Another factor to consider is that people are generally expected to act in accordance
to their intentions (Ajzen, 1988). While the present study measured self-esteem against
dependent variables time and cortisol, the handlers were instructed simply to move pigs
without consideration of time in the circuit. Therefore the handlers intentions or
pretensions may have been different from those measured (time and cortisol) in the study.

Gender

For the most part, gender did not predict behavioral approaches used by males contra
behavioral approaches used by females. Based on a national survey of pig stockpeople,
women constitute only 3% of that workforce (Miller, 1996), therefore there is a paucity of
information on female pig handlers. Although anecdotal, it is a belief among many pig
producers that women’s personalities are better suited for working in the environment of
the farrowing house. These same beliefs may suggest that males and females are suited
for working in separate phases of pig production and that selecting a stockperson may be
gender based. Our research would submit that when compiling the biological response of
juvenile pigs, such as behavior, time in the circuit, and cortisol, there is no difference
between males and females.

Human Cortisol

Human cortisol was associated with less time in the circuit and an increase with
human behaviors slapping and problem solving. Almost any type of physical or mental
stress can lead to an increase in cortisol (Guyton, 1996). Unpredictability and suspense

are effective stimuli for an activation of the adrenal system (Hubert and de long-Meyer,

83
1989). An increase in problem solving behavior in the first 50 seconds of time in the

circuit would likely be both physically and psychologically stimulating. Similarly,
slapping, considered an aggressive behavior, suggests a confrontation between the
handler and the focus pig, resulting in higher cortisol response. It is well documented that
the adrenal response of human subjects includes an anticipatory stimulus. In a number of
studies, Kirschbaum and Hellhammer (1989) investigated the changes in salivary cortisol
levels under psychological stimulation. Using a suspense film (“Psycho”) as a stressor in
humans to measure both actual and anticipatory adrenal response, this group determined
that only anticipation stress was a good predictor of cortisol concentrations. Similar
results were obtained in a study with young police officers facing a violent group of
football fans. In this case however, cortisol concentration in these police officers was
elevated both in anticipation of and during confrontation.

Surprisingly, human cortisol response to pig avoidance and investigatory behavior
was inversely associated with behaviors escape, escztum, and rooting. The focus pig data
confirms this negative association with rooting, although with less significance. The
present study also found an association between low grunts and lower human cortisol.
According to (Hafez and Signoret, 1969) low grunts are an indication of rooting in pigs.

In a review paper, Kirschbaum and Hellhammer (1989) explained that in mild
stressful situations not only the “stressor” but also the personality factors are important
determinants of salivary cortisol response. These authors support the theory of personality
factors by citing a study whereby children watched either a scary fihn or a control film.
The study found that highly anxious children showed increased cortisol concentrations

during both a scary (stress) film and a control film, while children with low anxiety did

34
not respond to either the stress or the control film with an elevated cortisol levels. The

determination of higher salivary cortisol values obtained by RIA for men when compared
to women is in agreement with one study published where males subjects had higher

basal cortisol values than women participants (Cooper et al., 1989).

Handler Strategies:

Interrelationship of the Behavioral and Physiological Response of Pigs

There are two main factors to which pigs respond when handled: the response to the
handler and environmental stressors such as the facilities, and the relationship or physical
position to other pigs. In addition to observing and documenting human to pig
interaction, another objective of the study was to emulate an on-farm environment by

providing an opportunity for pig to pig interaction and documentation of the responses.

Human Behavior and Pig Biological Response

The aggregation of handler behavior, problem solving, was strongly associated with
less time in the circuit. These findings corroborated with the hypothesis derived from an
earlier pilot study. Based on the preliminary pilot data, it was expected that the
unpredictability of pig behavior would constitute more problem solving or an increase in
behavioral elements necessary for success in moving pigs through the circuit in less time.
Problem solving involves decision making and the generation of alternative responses,

strategies, and behaviors needed to find a solution (Anderson, 1996).

85

Generally, analysis of individual handler behavior against covariances, time and
cortisol, revealed individual handler behaviors were not significant in reducing time in
the circuit, however, while moving the focus pigs, patting may be classified as a stressor
and bumping may be associated with lower pig cortisol. In contrast to other work, a
distinct category for non-aversive (pleasant) and aversive (unpleasant) behavior based on
time and cortisol, was not obvious. Such findings are contrary to a previous study
conducted by Hemsworth et a1, (1989) comparing fear and stress indices of sows to
predefined categories of human behavior. Hemsworth et al., (1989) found that the
stockperson behavior toward pigs was a good predictor of plasma cortisol and fear
response. The unpleasant behavior category containing hits, slaps, and kicks were more
aversive to pigs than the category of stockperson behavior containing pats and strokes. A
criticism of this study is the experimental bias as the human behaviors were pre-classified
based on intuitively accepted allocations of patting and stroking as pleasant behaviors and
slapping, kicking, and hitting as unpleasant behaviors. The confederates recorded the
amount of time each stockperson spent with each pig, and the number of bouts of
physical interaction within each classification of pleasant or unpleasant behavior.

Human behavior blocking and vocalizing were highly correlated and problem
solving was moderately correlated with both blocking and vocalizing. Blocking requires
body and hands to prevent pigs from moving backwards or escaping, thus it is a likely
that vocalization is an alternative and cognitive strategy for handlers to maximize the

success of driving pigs through the circuit.

 

86

Pigs Behavioral Response

Avoidance behavior turn and escape were strongly associated with higher time in the
circuit. Pigs perceive a person standing erect to be more threatening than one squatting
(Muira et al., 1996), however, a certain level of fear is desired and therefore it is
appropriate to stand when driving pigs. According to Gray (1987), escape and avoidance
are indices of fear. The causal stimuli of this fear can be based on intensity or novelty,
and may arise from social interaction, evolutionary danger or conditioned fear stimuli.
The pig will turn back and attempt escape when there is fear of unfamiliar conditions
such as change in floor material (Grandin, 1980), a funnel into a single race or a ramp
(van Putten and Lambooij, 1993) or interaction with another pig. It was noticed that if
one pig in the group escaped past the handler within the first 50 seconds of time in the
circuit, there were a significant increase in multiple escapes by pigs in that group. This
may be a learned success response by the pig, whereby as the more the pig succeeds, the
more persistent the pig is in its subsequent attempts and with some handlers, the pig
invariably wins.

Avoidance may not be the only expression of fear. High grunts emitted fiom the
focal pig were significantly associated with higher cortisol measures. Squeals and high
grunts were correlated to both escape and the esczturn ratio. This suggests that as the
esczturn ratio increases so does stress indicator, vocalization. This observation concurs
with research showing that high pitched vocalization was accompanied with escape
attempts (von Borrel and Ladewig, 1992). Based on data from the present study, it was
not evident if pig vocalization preceded the escape. Social species that collaborate in

defense against predators, such as pigs and humans, vocalize quite often when caught or

87
hurt (Broom, 1993). If fearful, an animal may squeal, emit high grunts, or remain silent

and immobile (e. g. freezing). It is important to note that vocalization may not have been
stimulated by handler interaction alone, but also from pig-pig interaction.

Nosing, an orientation behavior was inversely associated with turning and escape and
resulted in decreased time in the circuit. Orientation response is behavior that allows the
animal to investigate and observe the stimuli and as fear and avoidance behavior
responses wane, the animal will approach the stimulus and explore the area. Once the
animal is firlly acquainted, the exploratory behavior will be terminated and the animal
will move forward (Gonyou, 1993). Gonyou states that animals should be allowed to
investigate the surroundings without being forced. Additionally, orientation behavior is
argued to be negatively correlated with time since fear is related to low levels of
ambulation and exploratory behavior is related to high levels of ambulation (Whimbey
and Denenberg, 1967).

Based on analysis, pig behavior rooting was associated with an increased time in the
circuit. Although not supported statistically, observation of video tapes suggest that
rooting was not exclusively a exploratory behavior but a stereotypic activity used by the
pig as a stress coping mechanism often followed by an attempt to escape. Broom et al.
(1995) investigated coping ability of sows in different housing systems, and deemed an
excess of “normal” activities as drinking, rooting or chewing as stereotypic behavior.

Validation studies confirmed the reliability of the methods of salivary cortisol
collection, detection of free cortisol and the sensitivity of radioimmunoassay procedure
(see pp 51-56). However, in consideration of the minimal response of cortisol as an

indication of human and pig behavior, three plausible rationales are described. First, pigs

88

have an episodic circadian rhythm, as seen with the considerable inter-individual pig
differences as shown in Table 5, which may have skewed the overall results. Secondly,
mean basal cortisol levels of pigs in the present study were lower than levels referenced
in the literature (Zanella and Unshelrn, 1994). The pigs in this experiment were found
either rooting the flooring material or lying down close to each other. This may have had
a calming effect on the pigs both before and after the circuit, as environmental enrichment
aids animals in dealing with stressful situations and tends to reduce general fearfulness
(van Putten, 1988). The dirt and peat floors of the circuit and holding pen area would
sufficiently provide enough environmental enrichment to improve the coping capability
and reduce stress. The last and most likely reason is that, as mentioned previously, animal
stress response is based on the intensity, novelty and stimuli arising from social
interaction. The pigs used for this study had been herded at least 3 times from the hot
nursery to the cold nursery to the grower pens and again to the finishing pens.
Furthermore, group structure had not changed since the grower stage. Therefore, while
the circuit and obstacles were novel, the pig salivary cortisol levels in response to human

handling were most likely diluted.

Selection of Stockpeople

While it is interesting to speculate that human characteristics such as self-esteem
may be good predictors of handler success based on time required to move pigs or pig
stress indices, the data does not indicate such an effect. The self-esteem scores of

university students may be higher than scores representing the general population.

89
However according to Ravel et al, (1996) stockpersons investigated had higher global

self-esteem than the average person in Quebec. Human cortisol concentrations were
associated with time in the circuit and pig behavior however, requesting saliva samples
from a potential stockperson applicant is not advisable for most farms.

A significant finding in the present study is the relationship between problem solving
behavior by handlers and reduced time in the circuit. Since problem solving is defined as
the number of different behaviors by the individual within the first 50 seconds of the
circuit, it is worth noting that a person who responds to a task with an increase in
behavioral tactics may not indicate problem solving behavior traits. For example, at the
beginning of an assigned task, situation assessment and planning, would likely require
additional time whereas assertive or even aggressive behavior may be an immediate
response without time delay to action resulting in more behavior tactics during the initial
period.

While problem solving data has not necessarily established a cause and effect to
reduced time in the circuit, observing a potential stockperson as they navigate through an
unpredictable procedure such as driving juvenile pigs may provide insight on the
plasticity of that employee. In addition, problem solving techniques were not used more

frequently by males or females.

CONCLUSION

Problem solving is an important stockperson skill necessary for effectively handling
unpredictable situations encountered when moving pigs. The present study provides
qualitative information regarding the impact of on-farm handling strategies on
quantitative physiological and behavioral responses of pigs.

When compiling the biological response of juvenile pigs (behavior, time, and
cortisol), hmnan characteristics of self-esteem and gender were not strong predictors of
efficiency of handling, however pig responses were qualitatively affected by the problem
solving ability of the stockperson. Personality profiles may provide a better
understanding of the employees when recruiting or targeting recruits. However, as
suggested in this study, each stockperson is a compilation of genetic and personal
experience placed in a situation of unknown determinants of pig handling. Therefore, to
predict human behavior as it relates to personality traits, gender, and livestock handling
experience, it is important to establish a base rate data of handler strategies to better
predict hmnan pig interaction for future studies. Given that this is the first study of it’s
kind, the present study provides initial data of human behavior while handling juvenile
pigs.

Research over the last decade has concluded that many negative unpleasant actions by the

90

91

pig are actually induced by the stockperson. As presented, pig behaviors escape, turn and
vocalization proved to be good indicators of increased time to move pigs in the circuit.
These behaviors are more likely to be avoided when the stockperson moves pigs in small
groups, clears the pathway of debris and uses solid penning dividers and gates of
appropriate width.

The role of the stockperson continues to change as the industry endeavors to improve
productivity. Commercial pigs were traditionally transported and moved two to three
times before transported at market. Multiple opportunities for transport of pigs when
younger and smaller, provided an opportunity to train pigs in moving out of the pen and
into a passageway or onto a truck. This training reduces fear of novelty by the market age
when pigs are older, larger and physically challenging for handlers. With modern swine
production, however, weaned pigs are placed and remain in pens with the same penmates,
adequate in space allotment, until market weight. This unchallenging environment may
reduce the animal’s ability to cope in a stressful situation such as transportation. Present
information and future studies to identify the successfirl sequence of handler behaviors
required to move pigs, while monitoring pig response such as pig vocalization, may

provide effective indices when training stockpeople on proper handling techniques.

APPENDIX

APPENDIX

SURVEY OF PERSONAL EXPERIENCES

Some of the sentences found below describe different characteristics of a person. Some of them
are concerned with an individual’s reaction to events. Others are concerned with the nature of
relationships. As you read them, take a moment to think about yourself, your characteristics, and your
reactions to your experiences in events and personal relationships. Answer the following items with them
in mind. For each attribute, event, or personal reaction, we ask you to consider how it applies to you -
ranging from whether it doesn’t apply to that it strongly applies. Indicate your choice by marking the
appropriate response on the enclosed answer sheet. Fill in the corresponding circle on the answer sheet
with a #2 pencil that refers to the number that best represents your beliefs and impressions. Please do not
write on this survey.

Ngte: Words such as “close” and “intimate” refer to psychological or emotional closeness with
others. By “others,” “peOple,” “partner(s),” and “close relationships” we refer to people who you
encounter frequently, including your parents, other relatives including your spouse or siblings, other
important adults, special friendships, romantic partners, co-workers, important acquaintances.

Using the scale below, fill in the appropriate number (1 through 5) on the answer sheet for each item.

Not at all like me Somewhat like me Very much like me
or or or
Strongly disagree Neither agree or disagree Strongly agree
1 2 3 4 5

I. I am generous with my friends.

to

I'm somewhat uncomfortable being too close to others.

. 3. I worry that others don't value me as much as I value them.
4. I don't mind asking others for comfort, advice, or help.
5. On the whole, I am satisfied with myself.
6. I would rate the overall functioning of my family as:
l 2 3 4 5
The members of my The members Of my
family function well family do not function
together well together

7. I quickly get over and recover from being startled.
8. I find it difficult to trust others completely.
9. I often worry that others don't or won't really love me.

10. I seek comfort from others when I'm troubled or ill.
92

Id 10
Id v-‘

L.)
L»)

93

. At times. I think lam no good at all.

I enjoy dealing with new and unusual situations.

. I worry about others getting too close to me.

I sometimes get frustrated and angry because no one loves me the way I'd like to be loved.

I'm not the kind of person who readily turns to others in times of need.

. I feel that I have a number of good qualities.
. I usually succeed in making a favorable impression on peOple.
. I don't like people getting too close to me.

. PeOple have often let me down.

I like to tell my partner(s) all about my day.

I am able to do things as well as most other people.

. I enjoy trying new foods I have never tasted before.
. It's risky to Open up to another person.
. I worry about being alone.

7 . I rarely ask Others for any kind of help.

 

26. I feel I do not have much to be proud of.
27. I would rate the warmth in my family as:
l 2 3 4 5
Warm and available Cold, distant and
uncaring

28.
29.

. I like to share new ideas with my partner(s).

I sometimes feel that getting too close will cause trouble for me.

I worry about being abandoned by others.

. I certainly feel useless at times.

. I like to take different paths to familiar places.

. It's best to be cautious in dealing with most people.

. I often get frustrated because Others don't understand my needs.

. When something good happens, I can hardly wait to tell certain people.

. I am regarded as a very energetic person.

. I feel that I‘m a person of worth, at least on an equal basis with others.

. I am more curious than most people.

. 1 find it easy to trust others.

. Often. jUSt when you think you can depend on someone. the person doesn't come through.

. I don't hesitate to ask for help when I need it.

94

42. I wish I could have more respect for myself.
43. I would rate resxct and regard in my family as:
l 2 3 4 _ 5
Lack of respect for feelings Consrstently respectful of
and messages of others others’ feelings

44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.

and messages
Most of the people I meet are likable.
Others often want me to be closer than I feel comfortable being.
I’ve generally been able to count on partner(s) for comfort and understanding.
I’m not very comfortable having to depend on other people.
All in all, I am inclined to feel that I am a failure.
I usually think carefully about something before acting.
Other people don’t take my concerns seriously.
I find that others are reluctant to get as close as I would like.
I’m comfortable having other people depend on me.
I take a positive attitude toward myself.
I like to do new and different things.
My daily life is full of things that keep me interested.
I rarely worry about others leaving me.
I would be willing to describe myself as a pretty “strong” personality.

I get over my anger at someone reasonably quickly.

95;

PART 2
BACKGROUND INFORMATION

The following are items and questions concern yourself and your family. For each item and
question please fill in the number on the scoring sheet that is the most accurate answer regarding yourself
and/or your family.

59. My sex:
1. Male
2. Female

60. My age at my last birthday:
1. 17 or 18
2. 19 or 20
3. 21 or 22
4. 23, 24, or 25
5. 26 or older

61. My ethnicity/racial group:

.Caucasian/Non— —Hispanic

African American/Non- -Hispanic

Hispanic/Latino

Asian American

Other (please describe your ethnicity/racial group on the margin of the scoring sheet)

Meww—

62. The kind of community in which I lived for most of my life:

large city (over 250,000 persons)

medium size city (between 50000-250000 persons)

small city (between 25000-50000 persons)

suburban community (village or town of less than 25,000 persons) near a city
rural

SAPPJN?‘

63. My prior experience with animals, as pets, “family members,”and/or as part of our family’s
business (e.g., agricultural, farm) was:

Very satisfying

Satisfying

Neutral

Dissatisfying

Very dissatisfying

P‘PP’NT‘

64. My prior experience handling livestock (e.g., pigs, sheep, horses) was:
1. Very extensive
2. Substantial
3. Small
4. None

96

65. Father's education:
1. Some high school or less
2. High school graduate
3. Some college or technical school
4. College or technical school graduate
5. Professional/graduate degree

66. Mother's education:
1. Some high school or less
2. High school graduate
3. Some college or technical school
4. College or technical school graduate
5. Professional/graduate degree

67. How often did you go home this semester?
ermm
2. Several times
3. Nearly every weekend
4. Only for the holidays

68. My current relationship status:
1. Single and not dating
2. Dating several different people
3. Dating the same person for the last year
4. Engaged
5. Married

YOU ARE NOW FINISHED. THANK YOU VERY MUCH FOR TAKING THE TIME TO ANSWER
OUR QUESTIONS. PLEASE MAKE SURE YOU HAVE YOUR CORRECT PID ON BOTH THE
ANSWER SHEET AND CONSENT FORM.

97

You understand this research addresses how the attitudes and interpersonal style of
handling by various individuals will relate to behavioural and physiological response of

pigs.

If you choose to participate, you understand that it will take no longer than a one-half
hour for the questionnaire, and if asked to volunteer for the handling study, you are
not required to remain longer than the two hour lab time slot.

You understand that the video tapes made of you managing a group of pigs within
this animal handling exercise, in which you are taking part, may be shown to animal
handling classes as part of their educational experience in better and less stressing
methods of handling pigs.

You understand that the investigation has been explained and that there are no
known obvious risks outside the normal handling practices which are written in your
”animal handling course” objectives. The project does provide full coveralls to protect
your clothing and high rubber boots to protect your feet and lower legs. The pigs may
defecate and urinate, but since the number of pigs is three, this is not expected to be
an offensive odour to you. Any manure or urine will be cleaned up between pig
groups. ~~ -~

You understand that prior to moving pigs you will submit a sample of saliva and your
pulse will be taken. You will then be instructed to move into the pens housing the
pigs. From this point you will then move three pigs through a circuit designed to
incorporate common features found in pig handling facilities (Figure 1). Each of you
selected as handlers will move animals involved in this study. After you have
completed the circuit, you will be asked to submit saliva samples and pulse rate will
be retaken.

You freely consent to participate in this research and understand that you may
withdraw participation at any time.

You understand that all results will be treated with strict confidence and all
individuals will remain anonymous in any report of research.

If you have any questions or concerns you can feel free to contact Dr. Adroaldo
Zanella at 517/432-4134 or Dr. Madonna Gemus at 517/432-2944.

Signature

 

Date

 

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