I

IIIIIIIIIIIIIIII

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I

SIGNIFICANT FACTORS IN THE
DETERMINATION OF CARCASS
QUALITY IN LAMB

Thcsis for the Degree of MS.
MICHIGAN STATE COLLEGE

WiIIxam A. Ljungdahl
I942

 

 

II Iuilflllr rIIIIiIf
IIJEIL.

SIGNIFICANT FACTORS IN THE DETERMINATION
OF CARCASS QUALITY IN LAMB

Thesis for Degree of II. S.

Michigan State College

M“
William AQ~W

v

191.2

 

THESES

 

SIGNIFICANT FACTORS IN THE DETERMINATION
OF CARCASS QUALITY IN LAMB

A THESIS
SUBMITTED TO THE FACULTY
OF
MICHIGAN STATE COLLEGE
OF
AGRICULTURE AND APPLIED SCIENCE

BYI I.V\

WILLIAM AKIWDM
IN
PARTIAL mm 01“ THE REQUIRWTS
FOR THE DEGREE 0F MASTER OF SCIENCE
IN
ANDLAL HUSBANDRI
EAST LANSING

JUNE 19h2

Acknowledgement g

The writer is sincerely appreciative of
the time and effort or all who helped with this
study. He is particularly indebted to Professor
G. A. Brown, Head of the Department of Animal
Husbandry, and Professor C. L. Cole, Associate
in Animal Husbandry, for their advice and guidance
in the planning and completion of this work.

Appreciation is expressed to Dr. W. D.
Baten, Associate in Mathematics, for his
assistance in the statistical computations.

The author also wishes to thank the
Experiment Station Chemistry Department for
making the chemical analyses relative to this
stucbr.

Table of Contents

I. Introduction
II. Review of Literature
III. Objects of the Investigation
IV. Experimental Haterial
V. hperimental Procedure
VI. Results of the Experiment
VII. Summary
VIII . Conclusions
IX. Bibliography
X. Charts:
I. Slaughter Lamb Grading Chart
II. Lamb Carcass Grading Chart
III. Live Lamb Measurements
IV. Lamb Carcass Measurements
V. Slaughter Chart
VI. Cutting Sheet

I. Measuring Instruments
II . Live Lamb Measurements
III. Width Measurements of Live Lambs
IV. A Side-View of the Lamb Carcass
V. A Back-View of the Lani) Carcass

VI. Photographs of Hotel Rack between
the llth and 12th Ribs

~0me

10

33’

1+3

13

15
16
18
19

21
22
23

25

XII. Tables:
I. Predicting Equations for the
Area of the Eye.Muscle
II. Correlations of Factors Related
to Carcass Grade
III. Correlations between Slaughter Grade
and.Percentage Yield of Cuts
IV. Correlations of Factors Related to
Percentage of Shoulder
V. Correlations of Factors Related
Percentage of Hotel Rack
VI. Correlations of Factors Related
Percentage of‘Loin
VII. Correlations of Factors Related
Percentage of Leg
VIII. Correlations of Factors Related
Weight of Shoulder
IX. Correlations of Factors Related
Weight of Hotel Rack
X. Correlations of Factors Related
Weight of Loin
XI. Correlations of Factors Related
Weight of Leg
XII. Correlations of Factors Related
Thickness of Fat over the Eye
Muscle
XIII. Correlations of Factors Related
Area of the Eye Muscle
XIV. Correlations of Factors Related to
Width or Depth of Eye Muscle
XV. Correlations of Factors Related
Dressing Percentage
XIII. Appendix:

Original Figures Pertaining to

the Study

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35

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36

#5

SIGNIFICANT FACTORS IN THE DETERMINATION
OF CARCASS QUALITY IN LAMB

W

Animal Husbandmen have long had quite definite ideas regarding
the more important factors in determining the value of lambs, either on
foot or in the carcass. There is, however, a lack of specific informa-
tion as to what factor or factors are the most accurate basis for such
work. It is, therefore, the purpose of this study to try to arrive at
some more definite criteria whereby the true value of the last; carcass
may be detemined.

At the present time carcass grade is determined by general
excellence with respect to such factors as form, or shape of body;
finish or fatness; and quality. The quality is determined by the color
and texture of the fat, lean, and bone, as well as by smoothness and
refinement in general.

”Type", as defined by Vaughan (12), is "an ideal or standard
of perfection, codaining all the characteristics which contribute to the
animal's value and efficiency for the purpose specified", and is the
standard upon which our breeding animals are selected. These standards
are, and to a large extent, should be determined by the requirements
for the most desirable carcass, as well as by efficiency from a production
standpoint.

There are among the several breeds considerable differences
in the appearance of the carcass. It is necessary, therefore, to prove
very carefully the advantages of one type of carcass over another before

am definite standards can be set up to compare either breeds or animals

-2-

of different types. Any'mmthod of predicting the percentage of the,

various wholesale cute and a more accurate system.of grading would.be

extremely'beneficial to the producer as well as to the meat retailer.
This study is limited to the correlation and relationship

of certain carcass characteristics and does not include any feeding

or management studies. An effort was made to find specifically what

factors are the most significant in the determination of the preportion

of wholesale cuts and the carcass value.

- 3 -

Review of Literature

A number of investigators in this country as well as in
England, Scotland, and South Africa have made studies comparing various
breeds of sheep as to carcass characteristics. There is a great differ-
ence in the type of these various breeds and in making these comparisons
certain carcass relationships have been shown.

Branaman (3), in comparing the Southdown and Hampshire breeds
at Illinois, indicated that the difference in the total percentage of
the four.most valuable cuts (namely: leg, loin, hotel rack and shoulder)
was very small and not statistically significant in these two breeds.
The fatness of the lambs varied considerably, and with an increase in
fatness, the preportion of lean decreased. There was a significant
difference in percentage of bone in the two breeds. The average differ-
ence in area of the eye muscle (a cross-section of the longissimus dorsi)
measured in square inches, was not statistically significant in the two
breeds, but there was a marked difference in the carcass weight of the
two breeds. Correlations were high between area of eye muscle and
weights of the following parts when Hampshires and Southdowns were con-
sidered as one group: right half carcass, lean in the half carcass,
loin eye muscle, loin.lean, and rib eye.muscle. No consistent difference
was noted in any of these animals in the color of the lean meat when
examined with the spectrophotometer.

Both physical and chemical analyses of the carcasses of the
two breeds showed a similar average degree of finish, and although the
Southdowns averaged slightly higher in ether extract and dry matter, the
difference was not significant. This work would indicate that comparisons

-4...

of these factors can be made irrespective of breed if the lambs are of
similar finish. Branaman also points out in his work that from an
economic standpoint lambs reaching the proper slaughter weight early

in the summer have some advantage in market price. Rather than market
unfinished lambs early in the season, this advantage in price may be
partially off-set by a higher market grade when the lanbs become finished
later in the sunlner.

In predicting the live weight of steers, Barton (1) points
out that there is some correlation with certain body measurements in
cattle weighing between 200 and 1,000 pounds. He does not advocate
this method of weight prediction. It is doubtful if such correlations
would be of value in predicting lamb weights due to their relatively
light market weight of from 75 to 100 pounds. An individual with experi-
ence and practice can usually estimate weight "by the eye" and "by the
touch" with considerable accuracy.

In "The Report of The Review Committee on Cooperative Meat
Investigations" (10) , under ”Grades and Measures”, the firmness grade
of fat on the lamb carcass showed a high negative correlation with the
amount of moisture in the tissue. The amount of fat in the tissues,
rather than the character of the fat determined the firmness of the fat
grade under the ordinary feeding conditions studied.

The cutting yields in relation to carcass weight and grade
showed that the cuts with more natural lean and bone make up a decreasing
percentage as lambs increase in weight and grade. When grades and weights
were constant, there were no consistent differences in cutting yields
of mutton-type and Ranbouillet lambs.

A number of lanb grading relationships were determined in that

-5-

stuw. The method of obtaining the correlations and the point of

significance were not given. Correlations between:

Composite slaughter and carcass grade + 0.83 1"- 0.005
Live and carcass grade for width of body 4- 0.81. t. 0.005
Live and carcass grade for thickness of

finish + 0.80 i 0.006
Live and carcass grade for plumpness of

leg + 0.82 t 0.006
Composite live grade and width of body 4- 0.97 t 0.001
Composite live grade and thickness of

finish +0.98 2 0.001
Composite live grade and plumpness of leg + 0.97 i0.001
Composite carcass grade and width of body 4- 0.96 10.001

Composite carcass grade and thickness of fat +0.97 10.001

Composite carcass grade and plumpness of leg +0.96 10.001

Correlation coefficients between such other factors as carcass
grade with weight of rib eye, rate of gain, and tenderness, ranged from t 0.1
to t 0.3. The above-mentioned study was a grouping of the results of a
nunber of individual experiments which included 1, SA? lambs.

The consuming public is guided to a considerable extent by the
eating quality of the carcass, which is determined by tenderness and
flavor. In Reference u. (10) in the. tenderness ratings reported by the
palatahility comittee no correlation above 0.10 was given with any item
except tenderness as Judged by the mechanical shear. Murphey (9) dis-
cussing the effect of fatness on the tenderness of 1am) , states that it
does not seem that fatness in itself is a good measure of the tenderness
of lamb. He suggests that fatness cannot be discarded because of its

effect on other palatability factors, and that certain inherited character-

-6-

istics may have an effect on tenderness.

Hirsel (7) drew a nunher of conclusions relative to the muscle,
fat and bone in the lamb carcass. The cannon bone showed a variable
length measurement with increase in carcass weight, indicating that bone
growth is not a weight determining factor at am one age. A long, thin
bone (cannon or shank) is more objectionable than a short, thick bone.

If the bone is too short and not thick enough, there is a decrease in
the thickness of the muscle covering. When the proportion of fat, lean
and bone was compared to weight of carcass, he found that light carcasses
(28 - 30 pounds) could be obtained at the expense of finish. In heavy
carcasses (over 50 pounds), there was a surplus of fat which lowered the
value of the carcass.

In most cases there was a quite constant increase in muscle
and fat measurements with an increase in weight. Contrary to Palsson's (8)
investigations, Hirzel (7) reported that there were considerable breed
differences in the width of the eye muscle. This may have been due,
however, to the different breeds his work included, some of which are
not found in this country. The depth of eye muscle showed greater varia-
tion than did the width. The measurement of thickness of fat over the eye
muscle increased steadily with weight gain, although the greatest amount
of weight was added by the increasing thickness of fat over the ribs.

In discussing the growth and development of the sheep,

Hammond (5 and 6) stated that although the percentage of fat, lean and
bone in the carcass can be predicted accurately from the composition of the
leg, the shoulder corresponds more closely to the composition of the
carcass as a whole than does any other out.

Palsson (8) in studying meat quality in sheep at Edinburgh found

-7-

that as an index of muscle, external factors are only of indirect value.
The weight of the forecannon can be used as an index of bone weight of
the skeleton. His results duplicated those of Remand (5 and 6) in
predicting the percentage of fat, lean and bone in the carcass from the
percentages found in the leg.

Workers in the Bureau of Animal Industry (11) found a correla-
tion of + 0.98 between the fat (ether extract) content of the edible
portion of the lamb carcass and the similar content of the edible por-
tion of the nine-rib cut from the same carcasses. The same correlation
value was given between the separable fat content of lamb carcasses
and the separable fat content of the nine-rib cut of those carcasses.
Predicting equations were developed for both of these factors. The
respective equations developed were: Percentage of fat (ether extract)
in the edible portion of carcass equals 3.58 plus 0.73 times the per-
centage of ether extract in the edible portion of the nine-rib cut, and
the percentage of separable fat in the carcass equals l..28 plus 0.72
times the percentage of separable fat in the nine-rib cut.

-3-

Objects of the Investigtion

The objects of the investigation were:

1.

2.

3.

It.

5.

To

To

To

To

To

study the factors most closely associated with
carcass grade and with the percentage yield of the
wholesale cuts.

determine the relative importance of width
and depth of eye muscle upon its area, and
to find the best predicting equation for area

from these measuranents.

find the relation of the size of eye muscle

to carcass yield.

study the importance of the thickness of fat

over the eye muscle.

study the effect of an increase in finish on
the chemical analyses of the fat and the lean
from the hotel rack.

- 9 ..
Eerimental Material

This study was made during the smarter of 191.1. The experi-
mental material used was taken from the Michigan State College flock,
and included six breeds and crosses of sheep: five Hampshires, four
Oxfords, four Shrapshires, six Rambouillets, six Rambouillet X Cotswold,
and seven Hampshire X (Rambouillet X Cotswold). Records were kept
separately on the various breeds, but this study is a composite of
the six breeds and crosses. A comparison of the breeds and crosses
was made from this same experimental material, but not as a part of
this study.

All of the lambs used were spring lambs, drapped during
191.1, and all groups were handled similarly prior to slaughter. The
lambs were creep-fed before being turned on pasture, but did not
receive grain while on pasture during the early smer. Those which
did not reach slaughter weight until late summer received grain after

the pastures became dry.

- 10 - ’
Qgemntal Procedure

Periodic killings were made as the labs approximated the
weight of 85 pounds. The lambs were on pasture so it was impossible
to kill them all at the same weight, but groups of from two to six
as nearly alike as possible were killed together. The average of the
final slaughter weights was 82; pounds.

The lambs were all handled similarly inmediately prior to
slaughter, being placed in a dry-lot the evening before slaughter. The
ewes were put in with them to keep the lambs from becoming too excited.

A committeeof five members of the Animal Husbandry staff
determined the slaughter grades the day before slaughter. After grad-
ing, it was necessary to shear the lambs to get the most accurate
measurements. These measurements, as well as the carcass measurements,
were made with standard measuring instruments obtained from the Bureau
of Animal Industry, United States Department of Agriculture.

The lambs were weighed again in the morning, Just prior to
slaughtering. The weight of the shorn wool was added to this to give
final slaughter weight. Standard slaughter methods were used. The head
was removed at the atlas Joint, the front feet at the lower breakJoint,
and the hind feet at the round pastern Joint. The breast bone was not
split at the time of slaughter.

Carcasses were allowed to chill at temperatures of 3A - 38
degrees Fahrenheit for a period of A8 hours. They were weighed at the
end of a 24-hour period and again at the end of the 48-hour period to

determine the shrinkage.
Carcass grade was also determined by the same grading committee.

Measurements of the carcass were then made. A uniform method of cutting

- 11 -

was used to divide the carcass into the so-called.wholesale cuts, the
weight of each cut being determined. ’Photographs of the hotel rack were
made according to scale, showing a cross-section of the eye muscle
between the eleventh and twelfth ribs. [Mechanical separation was made
of the hotel rack, dividing it into fat, lean and bone. Samples of the
fat and the lean Obtained in separating the hotel rack were analyzed
chemically for percentage of water and ether extract of both the fat and
the lean.

It was thought advisable to make more inclusive grading charts
for'both slaughter and carcass grades in this study, due to the brevity
of charts now being'more commonly used. For others who might use similar
charts, it is suggested that a different system of numbering be used.

If the grades were on a basis of 100 for the top of prime, then most
correlations with grade would give positive, rather than negative results,
which would be more convenient for the worker.

Average grades of the committee were used as the final grades.
The grading charts appear as they were used in this study. (Charts 1
and 2). Recording sheets for'both live lamb and carcass.measurements
were mimeographed in detail to eliminate the possibility of error.
(Charts 3 and A). Similar sheets were also used to record slaughter
data (Chart 5) for cutting records and chemical analysis (Chart 6).

The measuring equipment used and the points at which the measurements
were made are shown in Figures I - VI.

A uniform.method of cutting was used to eliminate as much as
possible the variability that results in making cuts by "chance". The
carcass was first divided into the saddle and the rack, leaving one rib on
the hind saddle. The leg and.loin were separated at the Joint between

-12-

the last two lumbar vertebrae. In breaking down the rack, the breast
and shank were first removed. The guide used was a line from a point
one-half the distance from the midpoint of the back at the last rib to
the navel, and a point two-thirds of the distance from the midpoint

of the back (back of the shoulders) to the sternum, and at right angles
to the shoulder arm. A nine-rib hotel rack was desired, so that cut was
separated from the shoulder between the third and fourth ribs. This left
a three-rib shoulder.

Area readings of the eye muscle were obtained by the use of the
planimeter on the photographs taken of the hotel rack, with the surface
between the eleventh and twelfth ribs being used. Area of eye was in-
tended to include only the cross-section of the longissimus dorsi muscle
and not the entire lean surface of the cut. The measurement for width
of eye muscle was obtained by determining the longest distance across the
rather eliptical-shaped eye muscle. The depth of eye was considered to
be the longest distance obtainable at right angles to the width measure-
ment. Some investigators have referred to "width of eye" as "length of
eye" muscle. These terms may be used interchangeably but it is felt that
the term "width" is less confusing and is used throughout this study.

Chemical analyses were made by members of the Experiment Station
Chemistry Department for ether extract and water content of fat and lean,
using the approved method outlined by the Association of Official
Agricultural Chemists.

Because of the inter-relationship of certain measurements which
are believed to be dependent upon each other , two or more factors were
grouped together in some instances to get a more accurate relationship

in analyzing the data.

- 13 -

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- 15 -

CHART 3

Live Lamb Heasurements

Length:

(1)

(2)
(3)
(A)

m
(1)
<2)
(3)
u.)
(5)
(6)

Death:
(1)

(2)

(3)
(h)
(5)

Horizontal from.pinbones to front of chest at base

or throat.‘OOOOOOOOOOOOOOOOOOOOO.QOOOOOOOOOOOOOOO
Pinpoints to front edge of hooks..................
Front edge of hooks to the last rib...............

PinPOints to base Of DGCkOOOOOOIOOOOOOOOOOOOOOOOOO

Through the shoulder (widest point)...............
Narrowest point just back of shoulder.............
Loin back of last rib.............................
Loin, front of hooks..............................
Through the thurls (behind the hooks).............

Across the hacks...000000.000000000000000...000000

Tap of shoulder to floor of chest between
the front 16880000....OOOOOOOQOOOOOOOOOOOOOO0.0..

Just back of shoulder to bottom of chest
behind the front 1688.00.00.000000000000.0o00.00.

Floor of chest to the ground......................
Tap of hooks to bottom.of rear flank..............

From.the rear flank to the ground.................

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

-16...
CHART a

lamb Carcassvfleasurements

Width:

(1)

Through Shoulder...O‘COOOOOOOOOOOOOOOOO00.0.0.0...O

(2) Narrowest point Just back of shoulder..............

(3) Maximum.spread of rib..............................

(A) Narrowest part of loin.............................

(5) Legs at base of tail (Line drawn through

pj—nboneS)..............C..........C.........Q.....

29.2w;

(1) Just back of shoulder to floor of chest............

(2) Over loin through rear flank at narrowest point....
Circumference:

 

(1)
(2)
(3)

Heart gi-rthOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO...O
Legs (Base Of tail-)000000000000OOOOOOOOOOOOOOOOOOO.

Forerib (2/3 the distance from.midpoint of
baCR to stem‘m).......COCOCOOCOOOCOOCOOOCO0......

(a) Last rib (; the distance from midpoint of
back to navel)........COOOOCCCOOOCOCOO..OOOOOCO...
(5) Leg at bottom of twist.............................
(6) {Leg'(3/h the distance from.breakjoint above
hOCR to patella).........'..........O'COCOOOCOOOCO
(7) Foreleg (B/h distance from breakjoint above
pastern to point of e1bow)........................
Length:
(1) Front leg (EIbOW‘tO breakjoint above pastern)......

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

- 17 -

Lengthgfipontinued):

(2)

(3)
(h)
(5)
(6)

(7)

Hind leg:
Patella to breakjoint above hock.................

Breakjoint above hock to breakjoint above

paflemOO0.00CCOOOOOOOOO0.0...OOOOOOOOOOOOOOOOOO

From.line perpendicular to breakjoint above
hOCK to bOttom Of tWiStOOOOOOOQOOOOOOOOOOO0.0...

Point of shoulder to breakjoint above hock..........
POint Of BhO‘flder to PatenaOOOOOOOOOOOOOOOO00.0.000

Articulation between last 2 lumbar vertebrae
to articulation between last 2 thoracic
vertebrae (l rib on loin)..........................

Articulation.between last 2 thoracic vertebrae
to articulation between 3rd and hth thoracic
vertebrae (9'1‘ib raCk)OOOOOOOOOOOOOO00....00......O

Articulation between 3rd, and hth thoracic
vertebrae to anterior of lst thoracic
vertebra (3-rib chuck).............................

 

 

 

 

 

 

 

 

-18-

CHART 5

 

Slaughter Sheet

~....: H.’ .0...................00....O z... .OCCOOOOCOCOOOOOOOCOOOC ::.
E Feed-lot weight 3

‘OCCOOOOOOOOOOOOOOOOOOOOOOOOOOO...00,000.00...OCOOOOQOOOOOOOOOOOO

2 Final slaughter weight 3

.00...0......00.00.000.00...0.0.0....0000000OOOOOOOOOOOOOOOOOOOOO

3 Content of stomach and intestines 3

$0.....OOOOOOOOOOOOOOOOOOOOQIOOOOCOO~OCO00......OOOOOOOOOOOOOOOOO
O

2 Empty body weight :

.0.00.0.00...00.000.00.00...OOOOOOOOO?OCOOOCIOOCOOOOOOOOOOQOOOOOOO

. wanm dressed weight :

5.0.0.0000...OOOOOOOOOOOOOOOCOO...00%...OOOOOOOOOOOCOOIOCOCOOOOOO

Chilled wei t(24 hours) .

COOCOOOOOOOOOgOOOOOO00......0.0...0.00000...OOOOOOOOOOOOOOOCOCOO.

Chilled weigh '

Dressing percentageh E

Inna: :
Chilled 2
Eupty :
Weight of Pelt and feet '

000...? .0.COOCOOOOOO-OOOOOOOOO~OOOOOOCOOOOO0......0....0....
0

Weight of head .

O...OOOOCOOOOOOOUOOOOCOOCOOOO’OOOOOOOOOOOOOOOOOOOIOCOOOOOOC.
0

Weight of fleece ° °

oeooeoooeeeeoeooeoeoeeooeooooo:oeoeeooooeeeeeoeoooeeecease...

iscera full '

O OOOOOOOIOOOOOOOOOC0.0.0.0....0...;000000000OOOOOOOOOOOOOOOOO...
O
C

0.00......COCOOOOOOOOOOOOO0.000000COOOOOOC

Viscera

.00 v.0...OOOOEOOOOOOCOOOOOOO0.......{OOOOOOOOOOOOOOOOOOO0.......0.

Content of viscera

O0.00000COOOOOCOOOOOOOOOOO00.0.0.0;0000OOOOOOOOOOOOOOOOOOC0......

Gaul fat ° 3

0.0.0.0....0.00...COOOOOOOOOOOO‘OOOOOOOOOOOOOOOOOOOOOOOOOOOOQ.

O O

81‘ e o
0.0.0.0000...O....0....0...OOO‘OOOOOOOOOOOOOOOOOOOOOOOOOIOOQ.
O 0

1598“ ° '

..?.§?9??..........................3.............................3
Length of small intestine ' E 5

Length of large intestine 3 I

.00...0..0......OOOICOOOOOOOCOOOOOOO0......O.

0 0
Lung: capacity : :
:2:::: : H: :t: :: ::::::::::':'2::::::::::::::::::::::::::::::: :::'

COCOOOOCOOOOQCOOCCOQOOCOOOCOOOOOOI0.09.00.00.00.COO-OOCOOOOOCOOOCO

-19..

Chart 6

Cutting Sheet

;:::::::::::::::::::::::::::;:::::::::::5::::::::::;::::::::::;::::::::;
E..9.;g.?§r?§§§...;a‘...O...:..C..0...OOOEOCOOOOOCOOEOOOOOCCCCOi........s
E..F§:.gwg.%ggl..?.......O'CECCOOOOCO0.0:“.C...‘....i..0.......i........i
E..fi:.3§9¥.COCOOOCOCOOOOOOOEOO0.0.0.0.0;000......0;...OOOOOCOEOOOOOOCOE
. Wt. L . : ‘ z :
:O......?g...C0.......0...’.:..........00.0.0000....O'...‘.................
E..¥.:.¥?;9.0.0...‘.........:~....O...0.0:.C.........;..OOOOCOOOECO.......:
E..¥E:.¥?OC;.%?¥O0.0.CCC...i........C00:“...0.‘COOOEOCOOOOCCOOECO......5
2 Wt. Shoulder 3 3 3 3 I 3
.OCOOOOCCOOOOOOOOOOO00.0.0.0;0000OOOOOCWCOOOOOCOOOOOOOOOO0...“...OOO...
3 W . Breast, Flank 3 3 3 3 3
:C.00.00.0000COOOOCCOOOOOOOC~COOOOCOO...”O....0....:..........:....00...:
:COOOOOCCOOOOO...I0.........:......000...:0OOOOOOCOOO;..0.00.000;...000000:
; Wt. of bone from rib cut; ; : 3 :
E..¥E:.. of.£§§.f??¥.?é§.??§.0;..00000OOOOEOOOOCOOOOCOi...C.O00.03... 0.00.5
3 t. of lean from rib cut3 3 3 3 3
.000000000 .0...’............’....0....0......0.0.0.0;OCOCCOOOOOQO0.0.0....
3 i Ether extract in fat 3 3 3 3 3
z...O...OOOOOOQOCOCOCOOQ0.00:0000000...?OOOOOOOOOO:COOC00......00.0.0.0:
E..?.¥.§O e?‘%9.€9§00.0.0.....;..OOOOOOOOOEOCCCOCOOO0.3.0.000000030000000..E
E Z Ether Extract in lean E E E 3 3
.‘0......0......0000000......00000O...O00.00....OOOOO'CC00.00.00.000000000.
E ZWaterinlean E E E E E

1A B 0|
/ " ,
_ . D5

' 414 93.1 4

 

Figure I. Measuring Instruments, Standard Equipment Obtained from the
Bureau of Animal Industry, United States Department of Agriculture:

(A) Heasuring rule for height of animal, (B) caliper for width
measurements, (C) arm used to replace short caliper arms for width measure-

ment of shoulder and thurls, (D) centimeter tape.

 

Figure II

Live Lamb Measurements
Showing Length and Depth of Beth and Length of Leg.

Length from pinpoints to the front of the chest at base of threat.
Pinpoints to front edge of hooks.

Front edge of hooks to the last rib.

Depth from top of shoulder to floor of chest between the front legs.
Depth of body Just back of the shoulders.

Floor of chest to ground.

Depth of rear flank.

Rear flank to the ground.

- 22 -

 

Figure III

Width Measurements of Live Lambs

Through the shoulders.

Narrowest width just behind the shoulders.
The loin just behind the last rib.

The loin just in front of the hooks.
Through the thnrls just behind the hooks.

- 23 -

 

Figure IV

A Side-View of the Lamb Carcass

1. Circumference of both legs at the base of the tail.

2. Depth of carcass at the shallowest part of the flank.

3. Depth of carcass just back of the shoulders to the
floor of the chest.

 

Figure V

A Back-View of a Lamb Carcass

Length of shank from the breakjoint above the
heck to the bottom of the twist.

Circumference of leg at the bottom of the twist.

Width of the legs at the base of the tail.

Narrowest part of the loin.

Maximum spread of ribs.

Narrowest point behind the shoulders.

Width through the shoulders.

- 25 -

 

Figure VI
Photographs of Hotel Rack Between the llth and 12th Ribs.

The measurements for area, width, and depth of eye muscle and depth
of fat measurements were obtained from enlargements of similar
pictures.

- 26 -
Results

The lambs ranged in carcass grade from top prime to top
medium, with the larger proportion being in the higher grades. An
average of the grading committee shows that there were 15 prime,

8 choice, 7 good, and 2 medium grade carcasses. None of the lambs
were criticized for being excessively fat; however, the lambs which
were in the lower grades were lacking in finish.

Before making any study of the size of the eye muscle, it
was necessary to determine whether or not there was a significant
difference between the averages of the areas of the eye muscle in the
right and left sides of the carcasses. The method used was that given
in any statistics text book (2) for the test of significance between
means of small samples. The "t" value obtained was 0.181 which in-
dicates no significant difference between the means of the areas of

the right and left eye muscles.

 

 

 

 

 

Table I
Predicting Equations for the Area of the
Eye Muscle
Measurements Standard Error
Used Predicting “mations of Estimate
(1) Width A = a + bW = ~ 0.1.861 + 0.98 (W) 0.191.
(2) Depth A = a + bD 2 0.4338 + 1.2726 (D) 0.191
(3) W+ D A=a+bW +cDI-l.l762 +C.81(W)
4-1.071 (D) 0.153
u)wxn .A:h(m)= mmmcm) 0am
(5) ‘w.x D A = k + h (wn) = 0.1757-+ 0.6814 (we) 0.122

 

 

 

 

 

 

A=Mw w=m®h D=mmh

- 27 -

Table I shows the equations used for predicting the area of
the eye muscle from width and depth. Equation (1) predicts areas from
width and leads to the largest standard error of estimate (0.194 square
inches). The second equation (2) predicts area from.depth and leads to
g slightly smaller error (0.191 square inches). This agrees with
Hirzel's (7) work in which he states that depth is of greater importance
in determining area of eye than is width. It is probable that a greater
difference would have been shown if the lambs in the experiment had
been older, as depth of eye is a late-maturing factor, according to
Palsson (8). The third equation (3) gives a predicting equation from
width and depth measurements. The resulting standard error of estimate,
0.153 square inches, indicates that this is more accurate for predict-
ing eye area than either measurement used singly. Equation (h) is for
predicting the area from the product of the width and depth measurements.
Its error, 0.125 square inches, is smaller than that obtained by using
the first three equations. However, the smallest error found, viz.
0.122 square inches, was obtained by using a constant with the width
times depth measurement. This method of predicting is accurate to within
7 per cent of the mean of the area of the eye muscles.

In the following tables (I to XV) correlations of :t 0.349 are
significant at the 5 per cent level, designated *, and correlations of
2.0.Lh9 are significant at the 1 per cent level, designated **. (Fisher‘g).

Table II shows that most of the factors used.by the carcass
grader give highly significant negative correlations. Attention is
called to the fact that the grading charts had small numerical values
for the higher grades and large numerical values for the lower grades,

which resulted in some negative correlations. Number (1) of Table II

-23..

Table II

Correlation Coefficients between Numerical Value of Carcass Grade and:

(1) Thickness of fat over the eye..............................‘-0.739**

(2) Length of Carcass - Point of shoulder to
breakjomt above hockeeeeeeeeeeaeeeeeeeeeeeeeoeeeoeeeeeee+0.595“

(3) ILength from.breakjoint above hook to the twist.............4-0.823**
(1.) Length of carcass 4» length of breakjoint to twist. . . . . . . . . . + 0.731“
(5) Average depth (carcass)....................................—-0.083
(6) Circumference of leg at twist (carcass)....................-0.250
(7) Average width (carcass)....................................-—0.779**
(8) Average width + average depth + twist circumference........-0.555**

(9) Average Width + tWiSt circ‘mrerenceoeeeoeeee00000000000000.'0.6h7**

(10) "ED *6 8 ..0.......‘O...’................00......0...+0.855**

(11) L -+0 86
“+6 .0...COCOOCOOOOOOOOOCOOOCOOC0.0...O...0.0.0... . 7*.”

(12) a 7 00.......0.COCOCOOOOOOCOOOCOOOOC6......OOOOOCOO.+0.87%.“

(13) Slaughter gradeOOOOO'OO0.000000000000000000...0.0.0.0000... +0.78%

shows that there is a high correlation between fat covering and carcass
grade, an increased amount of fat giving a more desirable carcass.
Numbers (2), (3) and (h) show that a longbshanked lamb or one that is not
compact is a low grader. This may be due to some other factor which
affects the muscular development and fattening ability of these lambs.
The average depth.measurement (5) of the fore flank and hind flank does
not affect carcass grade, nor does the circumference of the twist (6).

In carcasses of similar weight, carcass grade is directly affected by

average width (7). ‘When (5) and (6) are added (9), they give a higher

- 29 -

correlation than when (5), (6) and (7) are used together (8), although
both give highly significant correlations. This indicates that
carcasses that are wide, deep and full in the twist are the most de-
sirable from a grade standpoint. To make a study of the effect of
type on grade, numbers (10), (11) and (12) were determined. The method
shown was used instead of running’mmltiple correlations because the
correlations Obtained can be compared with the other correlations ob-
tained in this study. The undesirable factor,length,is used as the
numerator and the measurements of desirability are used as the denomi-
nator. The length of carcass measurement was considered undesirable,
since carcasses are selected that are thick and compact. It is desirable
that the average width and average depth of carcass, and circumference
of the twist be as great as possible. These three measurements were
added together.
Table III
Correlation Coefficients between Numerical Value of Carcass Grade and:

(1) Percentage of hind saddle...............‘-0.108

(2) Percentage of rack...................... +0.108

(3) Percentage of breast and shank.......... +0.239

(h) Percentage of shoulder..................-+0.160

(5) Percentage of hotel rack................ -0.387*

(6) Percentage of loin......................-0.612**

(7) Percmtage of legOOOOOOOOOOOOOOOOO0.0...*OOwhfl

In Table III the effect of carcass grade upon the percentage
yield of wholesale cute is shown. Grade in this study does not show any
significant effect upon the percentage of fore (2) and hind saddle (1).

No significance was found in the percentage of shoulder (h) or breast

- 3o -

and shank (3). A significant difference is shown by the hotel rack ( 5),
and the loin (6) shows a highly significant difference. This means that
prime lambs have a larger pr0p0rtion of these two cute than do lambs
grading lower. The percentage of leg (7) is greater in the lower grade
carcasses. It is suggested that this may be accounted for by the fact
that there is a high proportion of muscle in the leg and also that there
is an increase in the length of shank. The greatest increase in thick-

ness of fat covering is over the hotel rack and loin.

Table IV

Correlation Coefficients between Percentage of Shoulder and:

(1) Length of shoulder (Vertebrae)... .. - 0.169
(2) Width of shoulder (Carcass)........ + 0.129
(3) Width of shoulder (live)........... + 0395*

Table V

Correlation Coefficients between Percentage of Hotel Rack and:

(1) Length of hotel rack (Vertebrae)... -- 0.071
(2) Width of hotel rack (Carcass)...... 4- 0.527**
(3) Width of hotel rack (Live)......... —- 0.279
(1.) Area of eye........................ + 0.01.3
(5) Depth of fat over eye.............. + 0.271

-31-

Table VI

Correlation Coefficients between Percentage of Loin and:

(1) Length of loin (Vertebrae).... + 0.217

(2) Length of loin (Books to
r1138) " Liveoooooooooooooooo "' 0.125

(3) Width of loin (Carcass)....... + 0.369%
(4) Average width of loin (Live).. - 0.051
(5) Depth of fat over eye......... +0.519**

(6) Area of eye................... +0.193

Table VII

Correlation Coefficients between Percentage of Leg and:

(1)
(2)

(3)
(h)

(5)
(6)

Length upper breakjoint to twist (Carcass)... +0.687**

Circumference of legs at base of
dOCK (CarcaSS).0......OOOOOOOOODOOOOOOOOOO. ‘00273

Circumference of leg at the twist (Carcass).. -0.073

Length upper breakjoint to lower break-
joint (Carcass)............................+0.43%

Width of thurls (Live)....................... +0.119

Length of pinpoints to hooks (Live). . . . . . . . . . —0.h9h**

Tables IV, V, VI, and VII show correlation coefficients be—

tween percentage yield of each of the four most valuable wholesale cuts

and a number of measurements which it was thought might affect them.

The significant correlations here are all positive. In Table IV, only

one measurement of the shoulder (3) was found to be significant and

that was taken on the live lamb. Neither. of the carcass measurements

(1) or (2) were of W value in predicting percentage. There is only

-32-

one measurement (2) in Table V which affects the percentage of hotel
rack; it is the width of the carcass over that cut. A similar width
measurement of the loin of the live lamb, Table VI, gives a significant
correlation with the percentage of that cut. A higher correlation was
obtained, however, by using the depth of fat over the eye muscle.
Substantiating what was suggested in Table III, that long-
shanked lambs have a high percentage of leg, it is shown in Table VII,
(1), that there is a highly significant positive correlation between
length of shank and percentage of leg. The length of the cannon bone (1.)
also gave a significant correlation, but it was not as high as (1).
In (6) a highly significant negative correlation was obtained which is
very hard to explain. It may be that increased length and thickness of
shank account for this correlation.

Table VIII
Correlation Coefficients between Weight of Shoulder and:
(1) Width of shoulder (Live)....... .. ... . .... +0.70%“
(2) Width of shoulder (Carcass). . . . . . . . . . . . .. + 0.671"m
(3) Length of shoulder (Carcass, vertebrae). . - 0.3!.3

Table IX
Correlation Coefficients between Weight of Hotel Rack and:
(1) Width of hotel rack (IAve)....... ... . . ... 4- 0.385*
(2) Width of hotel rack (Carcass). . . . . . . . . . . . + 0.601“
(3) Length of hotel rack (Carcass, vertebrae) - 0.01.7
(1.) Area of eye.......................... .... +0.676**

(5) Depth Of fat on eyeoeeeeoeeeeooeeeeeeeeee +0.551“

-33..

Table X

Correlation Coefficients between Weight of Loin and:
(1) Average width of loin (Live).............. {-0.184
(2) Length of hooks to ribs (Live)............ -0.ll7
(3) Length of loin (Carcass, vertebrae)....... +0.146
(1.) Width of loin (Carcass)...................4-0.529M
(5) Area of eye............................... +0.531**
(6) Depth of fat on eye mscle................ +0.501**

Table XI
Correlation Coefficients between Weight of Leg and:
(1) Width of thurls (Live).................... +0.328
(2) Length of pinpoints to hooks (Live). . . . . . . + 0.061

(3) Circumference of legs at base of
dOCk (carcass)00......COC.........OOOCC.+rOO86W

(1.) Circumference of leg at twist (Carcass)... +0.£.26*

(5) Length of upper breakjoint to twist
(carcass)ooeeooe0000000000000eeeooeeeeeo-oc365*

From an economic standpoint, the weight of the various whole-
sale cuts is not as important as their relative percentages. It was
felt, however, that it would be quite helpful to find the measurements
which have the most effect upon the weight of the various cuts.

Tables VIII, IX, X, and XI show this. The width of the shoulder (l) and
(2) is the best indication of weight of that cut as shown in Table VIII.

In Table IX the factor which gave the highest correlation with weight

- 34 -

of hotel rack was the area of the eye muscle. Other factors which are
highly significant are the depth of fat over the eye muscle, and the
carcass width.mmasurement. The live lamb width measurement correlation
is significant, but the length measurement is not. The weight of loin,
Table X, also shows that area of eye mmacle (5), width of loin in the
carcass (A), and depth of fat over the eye muscle (6), are highly
significant in predicting its weight. In Table XI a circumference
measurement taking in both legs at the base of the tail (3) gave a
highky significant correlation with leg weight. A circumference
measurement of one leg at the twist, and the length from the upper break-
joint to the twist, were both significant correlations, but not highly

80.

Table XII

Correlation Coefficients between Thickness of

Fat over the Eye Muscle and:

(l) Carcass grade.....................-0.739**
(2) Percentage of hotel rack..........4v0.27l

(3) Percentage of loin................-*0.519**
(1.) Weight of hotel rack.............. +0.551H

(5) weight or IOinOCOCOCOOOOOOOOOOOOOO*00501“

-35-

Table XIII
Correlation Coefficients between Area of Eye Muscle and:
(1) Gromh rateeoeooeoeeooe00.000000000000000. +Oo6h6”

(2) Narrowest width back of shoulders
(carcass)C.......OOCOO..................+0.268

(3) Average width of rack (Live)..............-+O.625**
(4) Average width of loin (Live).............. +0.501.**
(5) Ilaximum.spread of ribs (Carcass)..........-ro.416*
(6) Average width of loin (Carcass)........... +0.32?
(7) Circumference of leg at twist (Carcass)... e0.367*
(8) Percentage of hotel rack..................I+0.Oh3
(9) Percentage of loin........................ *0.193
(10) Weight of hotel rack......................'00.676**

(11) Weight 0f10511000000000.0000.eeeoeoeeeoeeo+0.531”

Table XIV

Correlation Coefficients of Factors Related to Width or
Depth of Eye:

(1) ‘Width of e e, and width of loin
(carcass§ooococoeeeeeooooooooeoeoeeeoeeo +00265

(2) Depth of eye, and circumference
of leg at twist (Carcass)............... r0.506**

All of the correlations in Table XII have been mentioned in
the tables preceding this one. They are grouped tagether here to show

the importance of an adequate covering of fat over the eye muscle.

Attention is again called to the fact that a negative correlation of
fat covering with carcass grade is a desirable characteristic.

Table XIII is a similar grouping of the factors correlated with

-36-

area of eye muscle. One correlation is mentioned here that has not
been mentioned previously in this study: the growth rate (1), which
is highly significant. This is of practical interest to the livestock
producer, because it points out a distinct advantage for rapid growing
lambs. The other correlations are explained in the discussion of the

preceding tables.

Table XV

Correlation Coefficients between Dressing Percentage and:

(1) Area of eye nmscle..........................+0.574H’

(2) Length from base of throat to pinpoints,
plus average length of 163................ -O.156

( 3) Average width (shoulder, rack, loin
md thurls)oooooooeeoeeeeoeeeeeeeooooooeoo+Oeh0h‘}

Table XV shows a highly significant correlation between dress-
ing percentage and area of eye muscle. The correlation between dress-
ing percentage and length of body plus length of leg was not significant,
while average width showed a correlation significant at the 5 per cent
level.

A correlation of + 0.786 was found between the ether extract of
the fat and of the lean from the hotel rack. The correlation between
the percentage of water in the fat and of the lean from the same cut was
4- 0.683. From these two correlations, and the statement that the firm-
ness grade of fat on the lamb carcass shows a high negative correlation
with the amount of moisture in the tissue, (Report of Review Committee)

some conclusions are drawn. It would seem that carcasses that are

criticized for being "wastv" or "watery" have a high water content in

both fat and lean and should be discriminated against. From the correla-

- 37 -

tion obtained on ether extract, it is assumed that the lean from those
carcasses with high ether extract is the most desirable as fat is

considered one of the palatability factors. Therefore, carcasses that
have a good covering of fat are higher in ether extract and correspond-

ingly lower in moisture content than lambs lacking finish and firmness.

-33..

Max

The eXperimental material used in this study was a group of
thirtyhtwo lambs, dropped during the spring of l9Al, representing the
HBmpshire, Oxford, Shropshire, Rambouillet, Cotswold X.Rambouillet,
and Hampshire X (Cotswold X Rambouillet) breeds. The lambs were all
handled similarly prior to slaughter. Weight of the lambs determined
the time of slaughter, the plan being to slaughter the lambs at approxi-
mately 85 pounds. Final slaughter weights averaged 82% pounds. Standard
methods of slaughter and cutting were followed.

Analysis of the data on size of the eye muscle showed no signifi-
cant difference in the area of the eye muscle in the right and left side
of the carcass. Predicting equations were set up for finding the area
of the eye by the use of the measurements of width and depth. It was
found that the predicting equation giving the smallest standard error
of estimate was the use of a constant (0.1757) plus the width times
depth measurements. The error of this measurement is within 7 per cent
of the mean of the areas of the eye muscles. These predicting equations
also showed that depth of eye is more important than width of eye in
predicting its area.

Depth of fat over the eye muscle varied directly with carcass
grade, and no lambs in this study were wasty in.their fat covering. The
factors associated with type, namely: compactness, width, lowbsetness
and thickness, showed a direct effect on grade. Depth of body was not
important. Slaughter grade showed a high correlation with carcass grade.

In studying the relationship of carcass grades upon the per-

centage of wholesale cuts, no relationship was found with yield of shoulder

- 39 -

or breast and shank. The percentages of loin and hotel rack were
significantly greater in the higher grades while the percentage of
leg was greater in the lower grades. Carcass grade did not affect the
percentages of fore and hind saddle.

Various body measurements showed a high correlation with the
percentages of the different wholesale cuts. The only measurement
showing any relation to the percentage of shoulder was the width of
shoulder in the live lamb. The same was true of the hotel rack, with
the exception of the fact that it was the width of the carcass over that
cut. Depth of fat over the eye was the best index of the percentage of
loin, although live width of loin was also significant. Lambs that were
long in their shanks and cannon bones had the largest percentage of leg.

Width of shoulder of either the live lamb or the carcass was a
good indicator for the weight of that cut. Area of eye muscle, depth
of fat over the eye and carcass width all varied directly with weight of
hotel rack and loin. The best indication of the weight of the leg is
the circumference of both legs at the base of the dock. Length of shank
and circumference of twist were also significant. The length of the
vertebrae in the shoulder, hotel rack and 10in cuts has no relationship
to the weight of those cuts.

A highly significant correlation was found between area of eye
muscle and the growth rate of lambs.

The ether extract of the lean varied directly with the ether
extract of the fat. The percentage of water in the fat varied directly
with that of the lean. It also emphasized the difference in composition
of the edible portion of the carcass as finish increased. The change

was largely a reduced percentage of moisture and an increase in ether

- #0 -

extract in both the fat and the lean. This showed that a carcass grader
may be justified in putting lambs in the lower grades when they lack

firmness of fat and lean in the flanks.

- Al -

Conclusions

 

Data indicate that there are three main factors closely asso-
ciated with the carcass grade: namely, slaughter grade, covering of
fat over the eye muscle, and type. The most desirable carcass type,
as shown by grade and yield, was found to be compact, wide-bodied, deep-
twisted, and short-shanked. Percentage of the shoulder and of the breast
and shank are not affected by carcass grade. The preportion of loin
and hotel rack increases with carcass grade, while leg decreases when
carcass grade increases.

Carcass grade had no effect upon the percentages of fore and
hind saddle in the carcass. The percentage of loin and hotel rack was
the largest in the higher grade lambs. The percentage of leg varied
inversely with grade. The yields of shoulder, breast and shank were not
affected.by grade. ‘Width of loin in the carcass and width of shoulder
in live lambs show positive relationship to the percentage of those cuts.
Width of hotel rack in the carcass was the best indicator of yield of
that cut. Long shanks and cannon bones indicated a larger preportion
of leg in the carcass.

There is no statistically significant difference in the size
of the right and the left eye muscle. Depth of eye muscle had a greater
effect upon size of eye than width. The best predicting equation for
area of eye is a constant (0.1757) plus the width times the depth of eye.

Factors showing a direct relationship with size of eye muscle
are: growth rate, average width over the hotel rack,¢and loin in the
live lambs. Circumference of leg at the twist and.maximum.spread of

the ribs were the best carcass measurements for indicating area. There

- 42 -

is no relationship between the area of the eye and the yield of the
various wholesale cuts.

The thickness of fat over the eye muscle affected carcass
grade more than it did the yield in weight or percentage of loin and
hotel rack.

Ether extract of the lean varied directly with that of the
fat. The same was true of the percentage of water in the lean and the
fat. This indicated that with an increase in covering there is an
increase in the amount of ether extract in.both the fat and the lean
and a decrease in the water content of both. Lambs that lack finish

and firmness, therefore, should be graded correspondingly lower.

2.

1..

5.

7.

9.

10.

Barton, W. M.

Baten, W. D.

Branaman, G. A.

Fisher, R. A.

Hammond, John

 

Hirzel, R.

Palsson, H.

Murphey, C. E.;

-43-

Bibliogaphz

The Relationship of Certain Bochr Measurements in
Beef Cattle.
Thesis for 11.3. Degree, Michigan State College, 1938.

Mathematical Statistics.
1938.

Some Factors in Lani) Production Associated with
Size and Type in mitten Sheep.

Thesis for Ph.D. Degree, University of Illinois,
1939.

Statistical Methods for Research Workers.
1936.

The Growth and Development of Mutton Qualities
in Sheep. .
Oliver and Boyd, London, 1921.

On the Relative Growth and DevelOpment of Various
Breeds and Crosses of Sheep.
Journal Agr. Sci. 11 : 367 - 1.07, 1921.

Factors Affecting Quality in Mutton and Beef, with
Special Reference to the Proportion of Muscle, Fat
and Bone.

Onderstepoort, Jour. of Vet. Sci. and An. Industry,
Vol. 12, No. 2, 1939.

Meat Qualities in Sheep with Special Reference to
Scottish Breeds and Crosses.
Jour. Agr. Sci. 29 : 5AA - 626, 1939.

Mackey, A. IL; Miller, J. 0.; and Cover, S.

The Effect of the Degree of Fatness on Tenderness
in Lamb.

Am. Soc. of An. Prod., 191.1.

U.S.D.A. Workers

Lamb Carcass Measurements as Related to Grade.
Report of Review Conmittee, Conference on Cooperative
Meat Investigations, Vol. 2. Grades and Measures, Lamb.

ll. U.S.D.A. Workers ‘
Growth, Fattening and Meat Production.
Yearbook of Agriculture, 1939.

11k liaughan, H. W.
Types and Market Classes of Livestock.
19A1.

APPEND_1__X_

-5-

Twhl

Individual Data of Lambs Slaughtered

 

 

 

 

 

 

 

 

 

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1 711...... 11

 

 

 

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(In Centimeters)

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Lamb Carcass Measurements

 

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Tth

PARTII

Lamb Carcass Measurements

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Lani: Carcass Measurements

 

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Table 1+

Percentage of‘lholssals Cuts

 

 

 

 

 

 

 

 

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Table 5

Weight of‘Wholessls Cuts

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-fl-

Table 6

Measurements of Thickness of Fat of the
Eye Muscle

 

 

 

 

 

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Chemical Analyses

 

 

 

 

 

 

t I

as 5 as a 5 5

§§§ Efi. fig E.

a .‘3 .3 as .‘3 a: a“: .35 g 6';

3°. 3°. 0% Vi
85.16 67.36 11.03
83.29 69.87 12.09
80.35 69.26 lh.hh
73.46 71.h8 18.79
73.33 72.09 18.65
79.1.5 69.98 15.07
81.70 70.26 13.21
76.10 67.77 17.09
78.63 69.53 15.23
84.80 67.27 11.15
83.05 68.28 12.32
85.71 55.98 9.96
86.7h 70.3h 9.81
78.37 72.38 16.31
86.72 66.71 9.16
76.64 70.63 16.35
71.15 71.25 20.32
65.22 71.86 26.02
72.53 71.20 19.35
76099 690 160%
76.71 72.56 16.44
66.07 73.95 23.73
86.03 66.26 9.88
81.30 67.04 12.66
77.59 69.52 17.05
78.47 69.60 16.05
67.72 72.L2 23.29
66.35 73.03 23.36
71.28 72.39 21.67
70.81 72.96 22.69
72.20 71.21. 19.68
79.10 70.99 16.52

 

 

51.

 

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