RELATIONSHIPS OF BIRTH ORDER AND - NURSING ORDER OF PIGS T0 _ PREWEANING GROWTH AND OTHER PARAMETERS . Thesis for the Degree of M. S. - MICHIGAN. STATE UNIVERSITY ‘ C-HUAM L. AI 1972, n-A A- LIBRARY Michignn State [1va airy f 3" smbmc av 3‘ \ HMS & SIIIIS' I MRI INC , Rm aaaaa ‘ IIIIIIIIIIIZIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 93 10515 2130 ABSTRACT RELATIONSHIPS OF BIRTH ORDER AND NURSING ORDER OF PIGS TO PREWEANING GROWTH AND OTHER PARAMETERS BY Chuan L. Ai Two trials involving 37 sows and their litters were conducted to examine (l) the relationship of birth order and nursing order, (2) the relationship of birth order and nursing order to preweaning growth, (3) the relation- ship of birth order and nursing order to blood parameters at 24 hours and 2 weeks of age and the relationship of these parameters to preweaning growth, and (4) the rela- tionship of teat order to milk production and the rela- tionship of milk production and pig growth. As a result of many observations and analytical measures the following conclusions can be reached. 1. There was no significant relationship between birth order and sex, nursing order of pigs, birth weight or preweaning gain of pigs. 2. There was a significant positive relationship be- tween birth order and several blood parameters at 24 hours of age including hemoglobin (r=0.34), Chuan L. Ai hematocrit (r=0.27) and per cent serum non-immune globulins (r=0.23) and a significant negative relationship between birth order and 24-hour (r=-.21) and 2—week (r=-.29) values of per cent serum y-globulin. Birth weight was significantly related to subse- quent weekly preweaning weights at one week (r=0.39), two weeks (r=0.27), three weeks (r=0.20) and four weeks (r=0.23) but was not significantly related to nursing order in either trial 1 (r=-.02) or trial 2 (r=0.05). Nursing order was firmly established within the first few days of life. Switching of teats in a horizontal or diagonal direction frequently occurred when the sow alternated the side on which she lay to nurse the pigs. The first—born pig usually fixed to either the most anterior or the most posterior teat. The second pig born either settled on the teat adjacent to the first-born pig or at the other extreme end of the udder. There was no definite pattern of teat order of pigs born later in the litter except the last-born pig which also fixed to a teat at one end of the udder. Chuan L. Ai Although not statistically significant there was a positive relationship between the concentration of serum y-globulin at 24 hours (antibody protein obtained from colostrum) and preweaning body weight gain (r=0.12). There was a highly significant correlation between five—week milk intake and five-week gain (r=0.78). The regression equation of five-week weight gain on five-week milk intake was Y=l.44 + .214x where Y=five~weeks gain in weight and X=five~week milk intake. Pigs gained 214 grams in weight for each kilogram of milk consumed. Birth weight was significantly related to subse— quent milk intake over a five-week lactation (r=0.42) and to five-week gain (r=0.48). The two anterior teats on either side tended to supply the most milk and thus there was a signi- ficant negative relationship between teat order and milk yield (r=-.27). RELATIONSHIPS OF BIRTH ORDER AND NURSING ORDER OF PIGS TO PREWEANING GROWTH AND OTHER PARAMETERS BY Chuan L. Ai A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Animal Husbandry 1972 ACKNOWLEDGMENTS The author is very grateful to Dr. E. R. Miller for his guidance, both in the study and in the preparation of this manuscript. The author would like to also acknowledge Dr. D. E. Ullrey, Professor E. C. Miller, Dr. W. T. Magee, and Dr. H. D. Hafs for serving on the author's guidance committee. Sincere gratitude is expressed to Dr. R. H. Nelson, Dr. E. R. Miller and the Animal Husbandry Department for the use of facilities and animals and for financial sup- port in the form of a graduate assistantship; the author thanks the department for enabling him to be engaged in graduate study at Michigan State University. The author would also like to thank Mrs. Susan Ekstrom and Miss Kim Miller for their skillful typing of this thesis; Mrs. Rosemary Covert for laboratory technical direction, and Mrs. Dee Calcatera, Dr. P. K. Ru, and Mr. Yu Yu for giving him their assistance and encourage- ment many times over. The author is eSpecially grateful to his parents for their encouragement to him in his education and every- thing else they have done for him. ii PERSONAL RESUME of Chuan Ai Address: 5, Lome 216 Sze-Wei Rd., Taipei, Taiwan Republic of China Phone: 770456 Personal Data: 6', 155 lbs. 26 years old Education: 1964-1968 Chung Shing University Animal Husbandry B.S. 1970-1972 Michigan State University Animal Husbandry M.S. Military Experience: Chinese Army. Lieutenant Officer 1968-1969 Employment Experiences: 1968-1969 Transportation officer in the Army. 1969-1970 International Quick Frozen Food Company, China, Manager and inspec— tion of all the food processes. Meat inspection. 1970-1972 Michigan State University Graduate Assistant Research and Teaching Assistant iii Chapter I. INTRODUCTION II. REVIEW OF LITERATURE TABLE OF Suckling Behavior . Nursing Interval Phases of Suckling Suckling Behavior of Species Milk Production Stage of Lactation Age Litter Size Position of Teats Breed Growth Milk Composition III. MATERIALS AND METHODS IV. EXPERIMENTAL PROCEDURE Trial 1 Trial 2 V. RESULTS AND DISCUSSION Trial 1 Trial 2 VI. CONCLUSIONS BIBLIOGRAPHY iv CONTENTS Page . . . . . . . 1 . . . . . . . 3 . . . . . . . 3 . . . . . . . 6 . . . . . . . 8 Other . . . . . . . 10 I O O O O O O 11 O O O 0 O O 0 11 O O O O O O O 12 . . . . . . . 13 O O O O O O O 13 . . . . . . . l4 . . . . . . . 15 . . . . . . . l7 . . . . . . . 20 O 0 O O O O O 22 . . . . . . . 22 . . . . . . . 24 O O O O O O O 25 . . . . . . . 25 0 O O O O O O 50 . . . . . . . 61 O O O O O O O 66 Table 9A. 10. 11. LIST OF TABLES Birth Order Related to Nursing Order During the First Four Weeks of Lactation . . Time of Farrowing and Duration of Parturition . . . . . . . . . Piglets Weight-Related Birth Order . . Birth Order Related to Twenty-Four Hour Hemoglobin Values . . . . . . . Birth Order Related to Twenty-Four Hour Hematocrit Values . . . . . . . Birth Order Related to Two-Week Hemoglobin Values . . . . . . . . . . . Birth Order Related to Two-Week Hematocrit Values . . . . . . . . . . . Birth Order Related to Twenty-Four Hour Total Serum Protein . . . . . . . Birth Order Related to Two-Weeks Total Serum Protein . . . . . . . . . Birth Order Related to Twenty-Four Serum y-Globulin . . . . . . . . . . Total Serum y-Globulin . . . . . . Birth Order Related to Twenty-Four Hour Serum Albumin . . . . . . . . . Birth Order Related to Twenty-Four Hour Serum Non-Immune Globulins . . . . Page 26 27 30 32 33 34 35 38 39 41 42 43 44 Table Page 12. Birth Order Related to Two-Weeks Serum Y‘GlObUlin o o o o o o o o o o o 45 13. Birth Order Related to Two-Weeks Serum Albumin . . . . . . . . . . 46 14. Birth Order Related to Two-Weeks Other Serum Non-Immune Globulins . . . . . . 47 15. The Relationship of Milk Production to Pig Growth . . . . . . . . . . . 51 16. The Relationship of Teat Order to Milk Production . . . . . . . . . 57 17. Simple Correlation Coefficients . . . . . 62 vi I . INTRODUCTION Many researchers and swine producers have ob- served that newborn pigs develop a preference for parti- cular teats during the first few hours although they may change teats during the first two days and then nurse the same teat or teats until weaning. This arrangement of pigs at the udder is termed the nursing order. Since different teats of the same sow may yield different quantities and/or qualities of milk, the choice of teat may greatly influence the early growth of pigs. This evokes a number of questions. What are the factors which influence the choice of nipple and subsequent orien- tation to that teat? What are the effects of nursing order upon preweaning growth and development? Are there any effects of early fighting upon later dominance struc— ture? What is the ability of a pig to claim and maintain possession of a particular teat? What are the effects of birth order and nursing order upon blood parameters such as hemoglobin concentration, hematocrit or serum proteins? This study, while not of sufficient scope to answer all of these questions, provides observations of (l) birth order related to nursing order during the first 4 weeks of lactation, (2) the relationship of birth order and nursing order to preweaning growth, (3) the relationship of birth order and nursing order to hematological parameters of hemoglobin concentration, hematocrit and serum proteins and the relationship of these parameters to preweaning growth and (4) the relationship of teat milk production to preweaning growth. II. REVIEW OF LITERATURE Suckling Behavior It is often asserted that during the suckling per— iod each member of a litter has its own teat, i.e., suckles regularly at a particular nipple. This suckling prefer- ence is not without practical interest, for it means that some pigs in a litter obtain very much less milk than others since different gland sections of the udder may secrete very different quantities. Several researchers cited by Donald (1937b) have made reference to this pheno- menon. Donald (1937b) evaluated the nursing orders of five litters after the fourth day of age. Following numerous observations, he concluded that the chief fac- tors influencing the number of departures from the normal distribution during suckling appears to be the number of pigs in the litter, the suckling behavior of the sow and the uniformity in the udder. There was much evidence to support the hypothesis that each piglet in the litter prefers to nurse on a particular teat. Most "errors" in teat choice were made by piglets nursing from teats in the middle of the udder, while piglets at either end were rarely found out of position. Data taken when the sow was lying on her right side indicate that most errors were horizontal in nature. The fixation on an individual teat and the es— tablishment of the social hierarchy occur simultaneously (Van Loen and Molenaar, 1967). When there are fewer pig- lets than teats the posterior teats remain unemployed. With some exceptions (England §E_Elrv 1961) piglets which are heavier at birth tend to appropriate the anterior teats (Allen and Lasley, 1958; McBride et_al., 1965). Even when litters are experimentally homogenized with respect to bodyweight, the correlation between birth- weight, teat order and subsequent growth persists (Lodge and Pratt, 1963). Hafez and Signoret (1969) observed that piglets which change their preference for a particular nipple during the early part of the suckling period attempt to move anteriorly. Occasionally, one piglet is left to suckle the two rear most teats when all others are occu- pied. In addition, pectoral teats are in a region which is safer for the pig than those teats near the dam's hind legs. Piglets suckling anteriorly are less apt to be moved if the sow should rise. Donald (1937b) and Gill and Thomson (1956) also noted that piglets appear to prefer the more anterior teats over the others. Donald (1937b) observed that in the first day or two after parturition the desire of the piglets to suckle on an- terior teats was stronger than the desire to retain one particular teat. McMeekan (1943) observed two cases where piglets suckling the two inguinal teats were es- pecially heavy at weaning. A piglet which suckles two teats usually divides its attention quite unequally be- tween the two. Donald (l937b) described that the chief means of recognizing teat location is by an appreciation of the conformation of the sow's udder as a whole. Unpaired or unequal size of udder sections help in this recognition. McBride (1963) suggests that a sense of smell and thereby reCOgnition of neighboring piglets as well as sight of the udder may be important in teat recognition. He ob— served a nose-rubbing behavior which did not seem to be associated with the normal massaging to obtain more milk and he assumed this to be some type of "marking” behavior. As a result of the marking procedure or some olfactory cue the piglets were able to identify teats hidden under the sow. However, when Donald (1937b) coated sow udders with mud or a scented substance the positions of the piglets was unchanged. Hafez and Signoret (1969) described that the sow selects a definite place in the pen where she lies down for nursing. She is induced to assume the appropriate position when the piglets first massage the udder. Sows usually Spend an equal amount of time on the right and left sides while nursing and favor the standing position more frequently later in the lactation. Sows do not turn over during a single nursing period. Some sows always lie on one particular side and others favor standing posi- tion while nursing. Feral and phacochoerus pigs frequently nurse in a standing position (Fradrich, 1965). Gill and Thomson (1956) mentioned that although sows followed different behavior patterns, they lay ap- proximately equal time on either side. Piglets could not massage the udder so forcefully when the sow adOpted a standing position at nursing time and those sows which favored this position produced a correspondingly lower total yield than those which favored the lying position. Nursing Interval Shepperd (1929), Schneider (1934), Donald (1937a), Wells gt_al. (1940), Niwa §£_313 (1951), Smith (1952), Berge and Indrebo (1953), Braude (1954), Barber gt_al. (1955), Hafez and Signoret (1969) and Mahan gt_al. (1971) have studied nursing frequency of pigs. Hartman gt_gl. (1962) observed that the nursing interval varied from 60 to 90 minutes with the majority being near 60 minutes. He noted no significant difference in nursing interval between day and night nursings. Hafez and Signoret (1969) and Mahan gt_al. (1971), however, observed a shorter interval between nursing during the day than at night. Niwa gt_al. (1951) and Mahan et_al. (1971) noted that the frequency of nursing declines through the lactation. Fre- quent suckling increases the sow's milk yield. Sows nursed at l-hour intervals produced about one-third more milk than those nursed at 2-hour intervals (Barber et_313, 1955). The suckling rhythm of feral swine in zoological gardens is similar to that of domestic breeds, but in the wild nursing occurs less frequently (Fradrich, 1965). The nursing frequency of neonatal pigs is very irregular immediately after parturition, but soon a reg- ular schedule is established (Smith and Hutchings, 1952). In general, the interval between nursing does not increase as laction progresses, particularly through the first 5 weeks postpartum. Salmon-Legagneur (1956) found that the mean interval between nursings during the first week of lactation was 67 minutes, and at 7 to 8 weeks the interval was 74 minutes. These results conflict with Wells et_al. (1940) who found approximately l-hr. intervals during early lactation and 2- to 3-hr. intervals at 8 weeks. Such differences can be explained in part by the work of Lenkeit and Gfitte (1957) who found that the number of nursings was influenced by the milk production of the sow. Thus, as milk production declines, which is common in late lactation, the nursing frequency decreases, Mahan et_al. (1971) found that the variance of cumulative quanti- ties of milk decreased as the duration of milk production estimations increased. The 4-hr. variance was significantly (P<.02) larger (Snedecor and Cochran, 1967) than of periods of 8-, 12- or l6-hr. duration. An additional 10% decrease in the variance was indicated for periods longer than 8 hours. Phases of Suckling Three phases of suckling may be recognized (Hafez and Signoret, 1969). The first phase is a touching phase. During this phase the pigs in the litter touch the sows teats making the sow lie down. As soon as the sow takes the nursing position the young touch the udder very vigor- ously for about one minute. The duration of this touching or nosing increases steadily from birth to weaning (Hafez and Signoret, 1969). Barber et_al. (1955) suggest that the secretion of neurohypophysial hormones in response to this stimulus is delayed as lactation advances. The second phase is a milking phase. The touching phase stOps abruptly, the young become quieter and draw back their ears. The sow's vocal sounds change from slow and low tones to quick and heavier sounds. The pigs rapidly consume the milk which is let down at this time. This per- iod of milk let-down averages less than 30 seconds (Niwa et_al., 1951; Barber gt_§l., 1955). Whittlestone (1953) found little variation in the duration of milk flow among Berkshire sows when a standard dose of oxytocin was used. The third phase is a quiet phase. The milk let—down phase also stOps abruptly but the pigs continue to nurse. Pigs generally continue nursing the teat for another 2 or 3 minutes after milk let-down has stopped but it may last for 15 minutes before the pigs give up the notion that there is more milk available and they go and lie in the creep area. During this post let-down period the sow is also quiet, making low and soft tones. Gill and Thomson (1956) assert that milk ejection is a reflex process which is most probably stimulated through the massage of the udder by the complete litter. Nursing then follows a consistent behavior pattern which can be divided into three parts, initial massage, milk ejection and final massage. The final massage phase occurs after milk has stOpped flowing and the massage rhythm is slower than that of the initial massage. During early lactation nursing ends when the piglets fall asleep at the udder. Later, the sow often brings nursing to a halt by turning over on her udder or walking away. Sows with tender teats do not allow the piglets to massage the udder after milk let-down ceases. During the first 4 to 5 weeks of lacta- tion, once the piglets have satisfied their hunger, they fall asleep cuddling to the sow for warmth. Older piglets will first suckle the sow and then eat supplementary feed before resting (Allen et al., 1959). 10 Suckling Behavior of Other Species Tsai (1931) found that young rats most frequently suckled the fourth pair of nipples. He suggested that with regard to the nursing attitude of the dam this pair was the most accessible. In sheep it was stated by Brown (1961), Brown (1964) and Spedding (1965) that after about the fourth week of life each twin usually sucks from (is fixed on) a particular side of the ewe's udder, although evidence has been put forward (Ewbank, 1964) that in the early stages of lactation, all the ewes allowed one out of a twin pair to suckle with- out the other being present. From the 3rd to 5th week on- wards most of the ewes showed at times, a behavior pattern in which the ewe would call the lambs and one would arrive at her side before the other. She would not then allow the first lamb to suck until the second was present. It appeared that twins, on the average, suckled more frequently than singles during the first 4 weeks of lactation. By the 5th week the suckling rate was about the same, and after the 5th week the rate of suckling tended to be approximately equal for both twins and singles. About two-thirds of the pairs appeared by the 10th week to have a definite prefer- ence as to which side of the ewe's udder a particular lamb would suckle while the other third used the sides in a much more random manner. 11 Milk Production The gain made by suckling pigs during the first few weeks presumably depends on the milk-producing ability of the sow. Several attempts have been made to measure the amount of milk produced by sows during lactation. This has been done by keeping the pigs away from the sow except at nursing time and then weighing the pigs before and after nursing. Henry and W011 (1897) were the earliest men to measure the milk production of the lactating sow with the weight difference before and after suckling being attributed to the milk produced by the sow. Numerous re- searchers have used this method to measure sow milk yield. Hughes and Hart (1935) reported the average production of 79 sows suckling an average of 7.9 pigs to be 413 pounds of milk during a 8-week lactation. Bonsma and Oosthuizen (1935) reported 367 pounds as the average 8-week production of 25 sows during 52 lactations, in which each suckled an average of 6.7 pigs. Stage of Lactation Milk production varies in the sow during various periods of lactation. Henry and W011 (1897) reported that milk yield was small immediately after parturition but gradually increased with a maximum flow being reached about the fourth week of lactation. Most workers agree that the 12 peak in milk production is reached at the third or fourth week with a gradual decline thereafter (Hughes and Hart, 1935) (Greenslade, 1952), (Smith, 1959b) (Kovacs, 1954) and (Lalevic, 1953). Individual sows vary in the time re- quired to reach a peak in milk production. Some sows main- tain an optimum level until the eighth week of lactation once they reach their peak. This fact fits very well with the needs of the pigs. During the later part of the suckling period the pigs need less milk because they are large enough to obtain most of their required nutrients from a supplemental creep ration or by eating some of the feed fed to the sows. But during their first few weeks of life the pigs would be almost en- tirely dependent upon milk for their nutrients (Greenslade, 1952). The average milk supply increased up to the 23rd day of lactation, then it decreased slowly and from the 40th day on there was a rapid decline (Onderscheka, 1970). 593 With regard to the different age of sow or number of litters which she has farrowed upon milk yield, Allen and Lasley (1958) found that milk yield increases up to the third litter and possibly to the fifth or sixth. Milk yield was not observed in the same sows, however, for more than three consecutive litters. 13 Litter Size In general, milk production increases as the number of pigs nursing increases, although the milk available for each pig decreases. Many investigators have observed that the amount of milk which a sow produces is dependent upon the number of pigs she suckles (Schmidt and Lauprecht, 1926; Hughes and Hart, 1935; Wells, Beeson and Brady, 1940; Smith, 1952; Kovacs, 1954; Allen and Lasley, 1960). Berge and Indrebo (1953) reported that the average daily milk production of sows with small litters was 8.4 pounds whereas in sows with litters of 12 pigs it was 21.9 pounds. The average of 1.76 to 2.65 pounds of milk per pig per day was recorded with the pigs from the smaller litters re- ceiving the larger amounts. Lalevic (1953) reported that the production of sows suckling six pigs was 295.3 pounds of milk while in those suckling fewer pigs it was 280.0 pounds during the entire lactation period. He found a posi- tive correlation between number of pigs per litter and the amount of milk produced by the sow. Allen and Lasley (1958) observed that the number of functional mammae was signifi- cantly correlated with the number of pigs in the litter at weaning in all of the breeds and crosses. Position of Teats Studies of individual teat yields in the sow have resulted in some interesting observations. Donald (1937b) and Barber et a1. (1955) found that the milk yield was the 14 highest in the foremost pair of teats and decreased pro- gressively in posterior pairs. Wohlbier (1928) found that the amount of milk coming from different teats varied widely. He found that this variation was due largely to the consti- tution of the pigs with the most vigorous pigs obtaining the most milk. The most vigorous pigs, he felt, evacuated the teat more completely, thus providing a favorable stimu- lus to the productive capacity of the gland. Weak pigs were unable to empty the teat and therefore, gave little stimulus to production. After a few days, the teats occu- pied by the vigorous pigs were clearly recognized. In those teats not suckled, the milk production soon ceased. Gill and Thomson (1956) reported that among 64 pig- lets in 8 litters, 39 (61%) which suckled the 3 pairs of anterior teats got 83.8 per cent more milk than the 25 (39%), which suckled the posterior 3 or 4 pairs of teats. Onderscheka (1970) found that anterior teats ap- peared to produce the most milk while the posterior teats came next. Central teats were less abundant in milk and were left to weaker pigs. Breed Breed difference in milk-producing ability of sows has been indicated by some investigators. Allen gt_al. (1959) determined the milk production of sows of inbred Landrace, Poland, and Duroc breeds, and Landrace X Poland crossbreds by weighing the pigs before and after nursing. 15 Average milk production for a 6—week lactation period was 306 pounds for Landrace, 266 pounds for Polands, 236 pounds for Durocs, and 300 pounds for Landrace X Poland crossbreds. Growth The weight gains made by pigs are, of course, greatly dependent upon the amount of milk produced by the sow. Donald (1937b) found that the rate of gain is closely associated with the amount of milk obtained. Zeller, Johnson and Craft (1937) stated that a sow's performance beyond the number of pigs farrowed may be thought of as a combination of a progeny test of the sow and a measure of her direct nutritional influence on her litter. Berge and Indrebo (1953) observed that the weight gain during the first three to four weeks was chiefly determined by the milk yield of the sow and that improved fertility in sows must be accompanied by a higher milk production or an earlier use of supplementary feed if the weight gains are to be maintained. Barber gt_al. (1955) also noted a close positive relation between milk intake and live-weight gain during the first three weeks of the lactation, but supplementary food was available during that time. A correlation co- efficient of .98 was found between milk consumption and growth rate up to 19 days of age by Gill and Thomson (1955). Hartman and Pond (1960) also found a high positive correla- tion (.77) between growth rate and milk intake. 16 The weight gain for the first four weeks of lac- tation for each 10 pounds of milk was calculated for 32 litters by Hempel (1928) and was found to average 3.29 pounds with a variation between litters ranging from 2.42 to 5.48 pounds. This marked range in difference in litter requirements for each pound of gain was thought to be due more to the influence of environmental factors than to differences in the composition of the milk of the sows. Lodge and McDonald (1959) reported that of the total variation in 3-Week weight within litters 39% was associated with variation in birth weight, 67% with varia- tion in milk consumption to 3 weeks, and 80% with these two factors combined. Of the total variation in 8-week weight within litters, 30% was associated with variation in birth weight, 25% with variation in milk consumption to 8 weeks and 42% with these two factors combined. Lodge and McDonald (1959) also reported that 45% of the variation in 8-week weight was associated with variation in 3—week weight. An apparent correlation between the total milk yield and the total time spent massaging by piglets at each nursing was found by Gill and Thomson (1956). They determined milk yield and time spent massaging the udder before and after milk ejection. Further proof of this correlation was provided by a sow that lay on her left side during more than 97% of her nursings. The lower row 17 of teats was somewhat restricted as to its being massaged because it was less accessible than the upper row. Since this sow constantly lay on her left side, the left row of teats was essentially a restricted massage treatment. The result was that the piglets on the right side consumed an average of 46.0 kilograms of milk per piglet during the lactation while those on the left side averaged only 27.8 kilograms. Data from another sow with similar habits showed the same tendency. Milk Composition Milk composition varies by breed, feeding and management, lactation number, stage of lactation, age of'the sow, season of the year, and the dose of hormone used to stimulate milk ejection (Barber et_al., 1955) and even in the same sow the milk of different teats may vary in com- position, especially in fat content. Smith (1952) reported fat values of 9 and 15 per cent in two teats, simultaneously milked from the same sow. Willett and Maruyama (1946) compared the fat con- tent of milk during early and advanced stages in lactation from sows fed on three different rations containing varying levels of garbage. They observed that the fat content of milk increased with increased fat intake and also with ad- vance of lactation. They noted a great variation in fat content of milk with the sows receiving the highest garbage 18 ration, where the fat content was highest but not a con- stant daily level. Bowland gt_al. (1949) milked sows at parturition, the third day, the end of the first week and each subse- quent week throughout the 8-week lactation period. They observed that after an initial rise the fat content de- creased appreciably as lactation advanced. They considered that it was difficult to establish a trend for total solids, but that a low point appeared to be reached about the third week of lactation after which the total solids increased slightly. In the case of solids not fat there was a ten- dency to rise after the third week. Protein showed a de- cline until the third week after which it gradually rose. After an initial rise from the colostral stage the lactose was more or less constant over the whole lactation. The ash showed a very definite rise from about 0.7% in the first milk to between 1.2% and 1.3% in the eighth week milk. Dawn (1954) reported analyses through sixty-eight lactations of forty-four sows. He found that the protein content decreases until about the middle of the third week and then rises steadily as lactation proceeds. The lactose remains steady until about this same stage and then falls slightly over the rest of the lactation. Apart from a stationary stage during the third week, the ash content rises steadily over the whole lactation. The third week 19 seems to be a critical time for several of the major con- stituents because during this week there is a change in the direction of their trends. This does not coincide with the stage of maximum production, but appears some one or two weeks earlier. III. MATERIALS AND METHODS The subjects of the study were 37 sows and their litters from the November, 1971 and March, 1972 farrowings of the Michigan State University swine herd. Sows and litters were housed in the central farrowing facility at the Michigan State University swine farm. This facility consists of a 96 feet by 24 feet wing off the main barn with large thermOpane windows on the southern exposure. The building is fully insulated. Two thermostatically- controlled space heaters provide heat for this room. Three thermostatically—controlled exhaust fans and baffled, uniformly-spread inlet air provides draft-free ventilation. Farrowing crates are arranged in two rows in the facility on either side of a 6-feet aisleway. On one side of the aisleway there are 17 units (6.5' long by 5' wide) with the farrowing crate running the length in the center and an 18-inch wide creep area on either side. The floor on this side is solid concrete and these units are cleaned and bedded daily with soft wood shavings. There are 15 units on the other side of the aisleway and the pens are 20 21 6-feet wide allowing a 24-inch wide creep area on either side of the farrowing crate. The floor on this side is slotted with concrete slats under some of the units and aluminum slats under others. No bedding is used in these pens, however, a 3 feet by 2 feet piece of indoor-outdoor carpeting is placed on the slats in one of the creep areas and a heat lamp is suspended 2 feet above this pad. This provided heat to the pigs from above and insulation to pre- vent heat loss to the floor below. A heat lamp was also similarly hung over one of the bedded creep areas in units on the other side of the aisle. Room temperature was main- tained at about 80°F. Each unit provided a feed container directly in front of the sow with an automatic waterer directly beside the feed container. Sows were fed twice daily (8:00 A.M. and 4:00 P.M.) a 16% protein, corn-soybean meal ration fortified with minerals and vitamins. The daily feed of the sows varied with the number of pigs nursed and amounted to about 6 pounds plus 2/3 pound per pig nursed. The average daily feed during lactation was about 12 pounds. The pigs were ear notched for permanent identifi- cation during the first day of life. Needle teeth were clipped also at this time and tails were docked. A single 100 mg. injection of iron in the form of iron dextran was administered intramuscularly at one to three days of age. IV . EXPERIMENTAL PROCEDURE Trial 1 Eleven sows were moved into the farrowing house on about the 110th day of gestation. These consisted of 9 Yorkshire x Hampshire crossbred sows, one Hampshire sow and one Yorkshire sow. Average weight of these sows as they entered the farrowing house was 437 pounds. Constant attention was given to sows when it be- came apparent by let—down of the udder and ejectability of milk from the teats that parturition was imminent. As the piglets were born they were wiped dry, weighed and ear-notched for identification by birth order. Birth weight, sex and time of birth were recorded. When suckling began, teat order was recorded. After the entire litter was born nursing order was recorded twice daily (morning and evening) until one week of age and then recorded once daily until four weeks of age. In addition to birth weight, weights of pigs at one day, one week, two weeks, three weeks and four weeks of age were recorded. 22 23 Blood samples were taken from the anterior vena cava of all pigs at one day and two weeks of age for deter- minations of hemoglobin concentration, hematocrit, total serum protein concentration and electrOphoretic fraction- ation of serum proteins. Hemoglobin concentration was assayed by the cyanmethemoglobin method of Crosby §t_gl, (1954) using a Coleman Junior II spectrophotometer. Hema- tocrit was determined by the micro method (McGovern gt_al., 1955). Blood samples were centrifuged for 5 minutes at 10,000 rpm in an International "Hemacrit" centrifuge and read on an International micro-capillary reader. Blood taken for serum was allowed to clot in centri- fuge tubes and serum separation was achieved by centrifug- ing for 10 minutes at 3000 g in an International Company Model V centrifuge. Serum was then harvested by aspira- tion, placed in vials and stored at -20 C until thawed just prior to total protein and electrOphoretic determina- tions. Total serum protein was determined by the method of Miller (1959) and Optical density was read on a Coleman Junior II SpectrOphotometer. ElectrOphoretic separation was accomplished by the agar gel on film leader method of Leop and Lucile (1962). Densitometer scanning was per- formed on a Beckman, Model RB Analytrol for quantitation of the electrOphoretic fractions. 24 Trial 2 Twenty—six sows which farrowed in March, 1972 were used in this study, including 13 Hampshires and 13 Yorkshires. Milk production of these 26 sows was esti- mated by the method of Mahan g£_al. (1971). This con- sisted of placing the pigs with the sow at hourly inter- vals for an 8-hour period on one day each week and ac- curately weighing pigs just prior to and immediately after each nursing. The difference in weight of the pig before and after nursing was attributed to milk consumption. Nursing order was observed and recorded each week in order to assign milk yield to each teat nursed. When pigs nursed two teats or when nursing pattern was altered as the sow alternated sides, this was also noted and recorded. All of these measurements and observations were recorded weekly during a 5-week lactation. V. RESULTS AND DISCUSSION Trial 1 The relationship between the birth order and nursing order of the nine crossbred, one Hampshire and one Yorkshire litter is shown in Table 1. There is no particular side the sow lies on during parturition. Some prefer the left side, while others prefer the right side. Most sows remain on one side throughout the entire far- rowing, while others get up after farrowing has started and may lie on the other side to finish. The length be- tween the first-born and the last-born is quite a range (Table 1a). From these 11 sows the range was from 19 minutes to 5 hours and 30 minutes, with most of them around 2 hours. The time of day when they farrow is quite dif- ferent also, with some during the day-time and some at night. Five out of 11 farrowed at mid-day, with the rest in the evening or morning or midnight. As might be ex- pected, there was a positive correlation of litter size and duration of parturition (r=0.20). With regard to the relation between the birth order and nursing order, from Table l we can see quite 25 26 TABLE 1.--Birth Order Related to Nursing Order During the First Four Weeks of Lactation. Teat Position, Front to Rear Sow 4 5 6 7 8 9 10 ll Breed XB XB XB XB XB H XB XB XB Y XB H N h) Side Born R R L L R L L S RL R L Total 3 L5 R3 L4 R5 R4 X R4 L1 L6 X R3 9 4 R6 R4 R5 L3 L2 L2 R2 X X L1 R4 9 5 X X R3 L1 L6 L7 L1 R2 RL3 X L2 8 6 R4 L2 L1 R7 R2 L3 RL2 R1 L1 9 c? 7 L2 X L2 X X L5 RL1 X R6 5 E 8 L4 R2 R4 R3 L3 R3 R3 L3 8 a 9 L3 R1 L5 R2 X R6 X R5 6 10 R1 R5 X L5 R3 L7 5 11 R5 R1 R4 R5 X 4 12 R7 R3 R1 R1 L4 5 13 R2 X R2 2 14 R7 L6 2 Key: S=Stand or lie down both sides; XB=Hampshire x Yorkshire cross breed; HeHampshire; Y=Yorkshire; X=died; L=left side; R=right side; Side born=sow parturition position. TABLE lA.—-Time of Farrowing and Duration of 27 Parturition. Number of Duration of Litter Breed Pigs Farrowing Parturition (minutes) 1 XB 14 9:40 P.M. 162 2 XB 10 5:20 A.M. 98 3 XB 14 11:55 A.M. 95 4 X8 12 1:20 P.M. 132 5 XB 12 8:10 P.M. 95 6 H 5 1:30 A.M. 76 7 XB 8 10:35 A.M. 19 8 XB 9 8:58 A.M. 317 9 KB 7 2:30 P.M. 110 10 Y 14 4:43 P.M. 163 11 X8 10 10:30 A.M. 90 Average 10.46 123.4 28 clearly that the first-born piglet usually nurses the first teat or the last teat (8 out of 9 surviving first- born), as did the last-born piglet (8 out of 11). Usually, when the first-born piglet took the first teat, the last- born piglet took the last teat; but if the first-born pig- let took the last teat, then the last-born piglet took the first teat. The second-born piglet generally suckled the teat next to the first-born piglet, or suckled the teat farthest away from the first-born piglet (6 out of 9). The third—born piglet may follow the second, the fourth may follow the third, etc. but there did not seem to be any certain pattern. Ordinarily, when the piglet was born, as soon as he touched the ground, the first thing which he tried to do was to stand up and look for teats, starting from the last teat and going forward, trying different ones until he found the most suitable teat to his liking. The reason for fixing upon a certain teat is un- known, but some of the researchers have offered Opinions on this matter. Hafez, Sumption and Jakway (1962) stated that neither the physical nor the behavioral characteristics of the new-born piglet are correlated with their ultimate teat position. However, Hafez and Signoret (1969) reported that teat fixation and the establishment of a social hierarchy occur simultaneously. 0n the other hand, McBride (1963) said that teats seemed to be recognized by sight, smell and the recognition of neighbors, and he thought that the 29 teat order and the social order are not directly related. They are probably both dependent upon such competitive factors as body size and aggressiveness. If the correla- tion between teat size and birth weight reflects any ad- vantage in the teat order, then this would tend also to give social advantage to pigs with these qualities since social position and weaning weight contribute to subse- quent growth (McBride gt_al., 1965). Concerning birth weight and teat position, Wyeth and McBride (1964) found a regression equation of teat position on birth weight which was y=4.0-0.44x, where y is the teat used and x is the birth weight. The regression coefficient of -0.44 had a standard error of 0.19 (p<.05). The relation between birth order and piglet weight data are presented in Table 2. There was an extremely low correlation between birth order and birth weight in this study (r=0.01). There was a nonsignificant negative re- lationship between birth order and post-natal, pre-weaning gain (r=-.09). The correlations between the birth weight and one week weight, two weeks weight, three weeks weight, and four weeks weight are all statistically significant (r=0.39, 0.27, 0.20, and 0.23 respectively). These corre— lation coefficients are somewhat lower than that found by Hartsock (1970), in which birth weight was positively .muwamfim mo nonssz« mH.m N Hm.v N m.m N mm.N N hm.H m hH.H Va mv.v N Nb.m N mN.m N b.m N bw.N m HN.H MH Nm.v m mm.m m mm.v m bN.m m mv.N m VN.H NH NN.m w mv.m e mo.m v mm.m v Hm.N m «N.H HH mo.m m HN.m m mb.v m mm.m m ov.N o HN.H OH mm.m m mN.b m Nb.m m mm.m m hm.N h MN.H m mo.m b Nm.w h mm.v b mm.m b mv.N w vN.H m mm.m w 0.5 w mm.m w mh.m w m¢.N m mH.H h m bo.m m mN.m m mm.v m ov.m m mm.N m 5N1" m m.m h Hm.m b mo.m b om.m m mm.N 0H 0N.H m mv.v m mm.m m ma.m m mb.N m Ho.N 0H MH.H v mv.m m no.0 m mH.m m hm.m m Nv.N 0H 5H.H m vv.m m Mb.m m mN.m m mb.m m Nm.N 0H VN.H N om.m m mv.o m HN.m m Hm.m m 0N.N 0H mN.H H Iago sumo 4.02 Lexi .63 ..oz Ass. .uz ..oz Roxy .uz ..oz ioxc .uz ..oz “axe .us human xmosnv xmosnv xmmsnm xmosnm gumsla suuflm no no u nusouo p o .uonuo Buuwm woumammuunmfimz mumamnmuu.~ mamas 31 correlated with 21-day weight (r=.57) and with 21-day gain (r=.43). England and Rose (1963) found that the correlation between birth weight and weaning weight in swine was rela- tively high (r=.43). In 1964, Keeler and England reported that piglets heavier at birth gained faster to 7 kilograms body weight than piglets of lighter birth weight. However, a follow-up study by Keeler and England (1964), in which piglets averaging about 3.9 kilograms were removed from their mothers and full-fed milk replacer for 17 days, revealed no significant differences between lower birth weight piglets and higher birth weight piglets with re- spect to average daily intake, average daily gains, or efficiency of feed utilization. Veum et_al. (l967)'stated that pig weight gains were highly repeatable by week with an average correlation of 0.64, which differed significantly from zero (p<0.05). The within-sow correlations show a significant positive correlation between birth weight and pig weight gain for each week. I McBride eE_al. (1965) stated that about 19% of the variation in 8-week weight was determined by difference in birth weight. The relationship of birth order and 24-hour and two—week hemoglobin and hematocrit values is presented in Tables 3, 4, 5, and 6. There was a significant positive 32 x hm.¢ mm.m «H m.0H x mm.HH MH VN.m Nm.HH 0H.m m¢.0H mm.OH NH x Hm.m mm.m Hm.m mo.m HH mm.m N0.h hN.OH VH.HH mH.m mv.0H OH mm.HH x Nv.b mo.w m¢.0H mN.m mm.m mv.OH m mm.m moi no.0H hm.m mm.m 23m mm.m m.m m m. HN.mH x mN.h mm.m om.h x Hm.m x Hm.m h m“ ugh mm.m mm.m mmfi. Hv.m mm.b bN.HH Hm.m mag 2.6 m m mH.m vb.N mb.h No.m x m.h 09.0 mH.m mm.m mo.m mm.m m m «m.m H.v x x hm.m HN.h mv.m mv.0H mm.m mm.h H.m v mo.HH x mb.b mo.m mN.m mv.m hm.m mm.m ¢.b mm.m w.m m m.m no.9 mm.m vo.m mm.m m.b om.b Hm.m no.5 v.m mm.m N vm.m cm.m Nm.m hm.m o.m x mm.m mm.m mH.m 0.0 MN.0H H mx M mx mx mx m mx mx mx mx mx m3om HH 0H m m b m m v m N H Omaha .HE 00H\m .cHnonoEom .mmsam> cfinoamosmm usom usomusucmsa op wmumaum umwuo suufimuu.m mummy 33 x m.~H m.mm «H m.~m x 6.4m MH o.Hm m.mm H.n~ m.Hm ~.Hm NH x m.m~ ~.Hm o.m~ m.m~ HH m.k~ A.- o.m~ H.om m.m~ u.um 0H o.e~ x o.o~ m.- o.m~ m.>~ n.Hm m.~m m HZ Ham H.Hm 9mm 6.: fimw H.H~ 0.5 m m. «.8 x 9% HR m.H~ x 9m... x H.~m H. m 8.8 «.m... mam mam m.m~ RS «.3 Han A...“ «:8 m m ~.H~ ¢.m o.v~ m.m~ x o.m~ m.m~ ~.m~ m.>~ v.- H.A~ m m m.mH o.~H x x m.m~ «.mm ~.v~ m.nm o.Hm m.v« H.m~ v m.m~ x m.m~ ~.n~ m.m~ o.mH m.mm H.5m A.MN v.b~ m.m~ m v.¢~ a.mH H.~m o.m~ m.o~ o.mm m.H~ ~.m~ H.H~ «.Hm o.~m m m.m m.HH N.n~ m.b~ «.mm x «.mu m.m~ m.m~ H.m~ v.Hm H mx M mx mx mx m mx mx fix fix mx m30m HH 0H m m A m m 4 m N H woman a .uHHooumsmm .mmsHm> uHuooumsmm Hsom usomnmucwsa ou omuMHmm Hwouo nuuHmI|.v Manda 34 no.0 hm.m vH x mH.HH MH 0m.0H vm.m om.h vo.m NH om.0H mm.0H mn.0H mo.m HH mo.v Hh.b mv.b x cm.v MH.b OH x Nm.m x mv.m mo.OH m¢.m HH.0H m .u Hb.v m.m 23m m.m Nv.m mm.m med 0 m x Nm.OH x x om.0H x mr.0H N. O vm.m mv.¢ mo.m mm.m hm.m no.5 Nm.v x m m. x ww.m 0H.m mm.m mm.m mm.OH om.m x x m J x x x 5v.m hm.0H hH.h qo.m 05.5 «H.m mm.m v x HH.HH vb.m mm.m x mv.m mm.HH mm.m «N.OH vm.¢ m mm.m Nb.m mm.v x NN.@ mw.w h.m mm.m om.m hm.m N NN.m vb.0H mb.m mm.m x hh.OH x mN.0H oH.m mm.0H H w mx mx mx m mx mx mx mx mx mBOm 0H m m b m m v m N H owmum .He 00H\m .cHnonosmm .mwsHm> cHnquoamm xmwzuoze cu omuMme “mono 5.39.36 mamas 35 o.MN h.mN VH x m.mN MH m.Nm H.hH N.¢N N.mN NH b.em H.¢M w.mm w.HH HH m.¢H m.MN N.mN x H.®H m.VN OH 8 x H.¢m x N.¢m N.Nm 0.0m m.Nm m M. v.mH m.bH m.mH o.HN H.0N b.HH m.mN N no N m.vm x x b.mm x v.vm h m. m.mH v.mH m.mH m.mH H.Hm ¢.vN m.vH x m 1 x N.Nm m.wN N.Hm 0.0m N.mm H.mN x x m x x x b.mH v.Nm m.NN H.mN N.¢N m.wH m.hN v x N.mm m.Hm m.mm x m.Nm o.mm m.mN m.Nm h.mH m m.MH m.mH m.mH x N.NN v.HN o.hN n.0N h.mH w.om N m.mN N.mm H.Hm m.Hm x b.vm x o.Nm N.Hm m.mm H w mx mx mx m mx mx mx mx mx m3ow 0H m m h w m w m N H ommum » . uHuofimgm .mmsHm> uHuuoumEom xmwznoafl. on omuonm Hmouo fiHHmII.o 39B. 36 relationship between birth order and 24-hour values of hemoglobin (r=0.34) and hematocrit (r=0.27). This re- lationship might be expected, since the earlier born pigs would have access to the first colostrum and for a longer period of time than pigs which were born later in the litter. Having obtained more colostrum, the earlier born pigs should transfer the proteins obtained from this colostrum to their blood plasma, thus increasing the plasma volume due to the increased osmotic pressure and lowering the concentration of cellular components in the blood (Miller e£;313, 1961b). There was a non-significant negative relationship between birth order and two-week hemoglobin (r=-.10) and hematocrit (r=-.14) values. Since birth order was non- significantly negatively related to two-week gain (r=-.ll), any relationship which may exist between birth order and post-natal hemoglobin and hematocrit values could be expected to be positive rather than negative. Veum et_al. (1967) found a correlation coefficient between birth weight and hemoglobin at 12 days post partum of 0.34, but the correlation of hemoglobin and weight gain at specific intervals through 24 days post partum were very low (average r=.08). In the study of Veum et_31. (1967) pigs were not given iron treatment or creep feed but likely picked up iron from the sow's feces (Veum gt_al., 1965). Dimov (1964) reported data which indicate an inverse 37 relationship between hemoglobin and weight at weaning. Many researchers have noted this inverse relationship between pre-weaning gain and hemoglobin concentration (Miller et_al., 1961b) when there was equal iron intake. In the present study, each pig received a single 100 mg. intramuscular injection of iron, in the form of iron dextran, at 3 days of age and an inverse relationship between post partum gain and hemoglobin values would have been expected. Since blood hemoglobin and hematocrit values are highly correlated (Miller et_al., 1961b), whatever relationships exist between hemoglobin and other parameters would be expected to be similar to that of hematocrit and the same parameters. The influence of birth order upon 24-hour values of total serum protein may be obtained from the data presented in Table 7. While the correlation coefficient (r=-.l3) was not statistically significant, it did approach significance (p<.10). This negative relationship between birth order and 24-hour total serum protein value is that which should be expected, since the 24-hour value of total serum protein is largely dependent upon the pro- tein obtained from colostrum (Miller gt_al., 1961a), and early born pigs in the litter are likely to consume more colostrum. Twenty-four-hour value of serum protein (Table 7) and two-week value of total serum protein (Table 8) were selected as parameters, since the former 8 3 00.05 H0.vm «H m0.00 IIIIII 50.00 0H N0.H0 0v.N0 HN.55 00.00H 05.5v NH IIIII H0.H0 00.00 0<.00 No.00 HH V5.00 mN.50 mv.mv 50.00H 00.00 H0.H0 0H 05.50 IIIII mm.m0 00.50 0N.00 0N.00 Hm.H5 0v.mm 0 8 Nm.m0 0H.m0 0N.00 0H.00 00.N5 05.HOH 0H.¢5 50.00 0 n. 00.0HH III: 0060 N0.H5 00.50 IIIII 05.50 IIIII Hv.m0 5 m. 05.00H 00.00 Nm.00 0.v0 0.50 0N.v0 00.00 N0.00H m0.H0 vH.m¢ 0 m. H0.v0 HN.5N V5.00 00.¢0 5H.mOH 0H.5m 00.05 H0.05 vm.N0 50.00 VH.00 m 1 00.00 om.Hm IIIII IIIII mH.v0 v.55 0v.N0 00.N0 00.00H 00.N0 mv.0m v 05.00 IIIII 00.00 00.00 0m.v0H 0H.V5 N0.00 00.05 00.50 0H.05 0H.m0 m 0H.05 V0.N0 50.N5 Nm.00 00.50 v.55 0H.05 v0.05 00.00 NH.N0 00.00 N 00.05 mN.50 m0.N5 H0.v5 H0.H0 H0.m0 00.v0 50.H0 00.50 00.00 H5.v0 H 0x 0 0x 0% mx m 0x 0x 0x 0% mx m300 HH 0H 0 0 5 0 m V m N H 000mm HE\0E .chuoum Edumm H8909 .chuoum fiauwm Hmuoa usom Haomluucmsa on wouMHom umouo nuuHm||.5 mqmda 39 o.mm 4H --- om.om NH NH.N0 6H.Ho_ mm.nm Ho.mN NN.Nm NH --- o.Nm No.4m An.mm 6H.vq HH om.qh «N.Nm Nm.mm --- Hm.mN mN.Nm oH --- HES --- N93 3.3 3.3 No.2 m m. 9%: --- N08 36m 3.: 8.3 mfiov m m. --- 3.3 ..No.Nm --- --- --- --- 3.3 N m Nm.mN mo.mm «H.om NH.Nm mv.mv --- vu.o> «N.Hm m “u --- mo.No HN.vm em.0N No.55 HN.vm «N.Nm mo.NN --- --- m oe.om --- --- 64.40 NN.mo ve.mh Nm.mm mN.No mm.mo mm.Nm v --- mm.mm mm.mm NN.oo --- mm.mm Nm.Nm mm.NN me.mo No.Nm N mm.nm --- «N.mm --- Nm.mN HN.HN Nm.mm mm.nm NN.NN Nm.Hm N mm.mv Nm.mm mN.Nm mN.ON --- om.nm --- Nv.mm Hm.Hm NN.N¢ H M. mx fix mx 2 mx mun mx mx mx 0300 oH m m N m m 4 N N H oomum HEK0E .cHououm Eshom Haves .cHououm Esumw Hmuoa mxmmzlosa ou wouMHom uwouo nuuHm-I.0 wands 40 value could serve as an indicator of the quantity of colostrum consumed and the latter value could serve as an indicator of metabolic rate. The correlation of birth order and two-week serum protein values (r=-.12) is of the same order as that between birth order and 24- hour serum protein values (r=-.l3) and would indicate that there is no significant influence of birth order on post partum metabolic rate. Included in tables 9, 10, ll, 12, 13 and 14 are relationships of birth order and 24-hour or two-week values of serum y-globulin, non-immune globulins and albumin. At 24 hours of age the pig has the highest level of y-globulin that he will ever have (Miller gt_al., 1961a). This is almost exclusively due to antibody pro- tein obtained from colostrum. Percentage of total serum protein which was immune protein (Y-globulin) in the current study was generally higher than that observed by Miller gt_al. (1961a), indicating that the pigs in the present study, in general, obtained good nursings of colostrum. As with serum total protein, so also there is a negative relationship of 24-hour Y-globulin and birth order (r=-.21), and this is statistically significant (p<.05). This leaves little doubt that the first-born pigs obtain significantly greater quantities of antibody protein from colostrum than those pigs born later in the litter. One might expect this to be most pronounced in 41 0.00 H.0m vH H.om -- «.44 NH N.NN N.NN m.oo m.vm m.Hv NH -- N.Hm mN H.4m m.om HH N.HN cm N.mN N.NN N.mm N.NN oH N.NN -- - N.NN mm mm N.Nm N.NN HNN N .0. H38 N.NN . N.NN N.NN N.NN -- N.Nm -- m m N.NN -- N.NN oN o.om -- N.NN -- N.NN N o N.Nm NA N.NN N.NN N.NN N.Nm v.3 Rom H.NN 2. o m. N.Nv N.HN mm mm N.NN N.NN N.NN mm N.NN N.NN H.mm N «.mo N.NN -- -- N.NN H.HN N.NN m.mv N.NN N.NN N.Hm v H.mm -- om o.HN N.NN v.HN N.om N.NN N.NN Hm N.Nm N N.NN H.Nm N.NN N.om v.VN N.NN N.NN N.NN o.no N.NN N.NN N N.NN N.oo Hm N.NN N.0N o.No N.NN H.NN N.NN N.mo om H mx M mx mx mx m mx mx mx mx mx 0300 HH 0H N N N m N v N N H nouum N . 5333-» Snow .cHHsnoHo-> abumm H500 “somnhucmsa on oouMHom Macho nuuHm:-.0 mnmda 42 HN.om NH.NN vH NN.NN --- N.NH NH NN.¢N NN.N¢ mm.mm No.HN 0N.NH NH --- No.0m NN.mH HH.NN HN.oN HH om.mm No.Ne Nv.mH mv.Nm 0N.Nm NN.NH 0H --- No.3 HNSN 8.8 HNN NNHN N.OH N m 3.8 NoéN 3.2 NN.NN --- mNNv --- N m --- NH.NN HNNN NoNN --- No.$ --- NNNN H. m NN.NN Hm.mv NN.Nv NN.HN AN.NN NN.NN Nv.0N Nm.om 0N.NH o m Nw.m 00.NN NN.NN No.00 NN.NN HN.NN No.04 mm.vm H.Hm 00.04 N vv.NN --- N0.Hw NN.NN NN.HN «N.NN NN.vN NN.N0 «N.NN o --- Nv.Hv HH.4¢ NH.NN HN.NN No.4m q.Hv «N.NN mo.N¢ 04 N No.NN oN.oq NN.N¢ NH.N0 HN.¢¢ v.04 0N.NN o.mm «N.NN HN.Nv N No.04 NN.NN NN.N¢ HN.vm HN.NN NH.Nv NN.NN om.¢m No.0m 0N.NN H M Mun Mun mun m mun mun mx an mum m30m 0H N N N m N v N N H owmum H59: .530on; 033 H38. .cHHHHQOHU:> 5500 Happy-5.00 wands 43 0.5 N.0 vH v.HH III: 0N 0H 0.0 0.HH v.0 0H H.NH NH IIII N.HH 0H 0.0H «H HH N.0 NH 5.0H 0.0H 0.5 N.NN 0H 5.0H IIII 0.0H 0.0 0.0 v.0 0.NH vH 0 H.0H 0.0 0.0H H.NH 0 III 5.0H IIII 0 m. 0.0 IIII N.0 0.HH v.NH IIII 0.0 IIII 0.0 5 m“ 0.0 0.0 0.HH 0.5 v.0 0.HH 0H 0.HH 0.0 v.HH 0 m 0.0 NN 0.0H HH 0.HH 0.5H H.HN HH 0.0 0.0 0.0 m m. 0.5H H.0H IIII III: 0.0H 0.0H 0.HH 0.HH 0 0.0 0.0H c N.0H IIII 0.0H 0.0 0.0H H.0H NH 0.HH 0.0 v.0H N.0 0 0.0H 0.5 0.HN 0.HH 0.HH 0.NH N.HH 0.0 0.5 N.0 N.0 N 0.0H H.0H 0.0 v.0 5.0 5.NH 0.NH H.0 0.0 5.0 0.0 H 0% M 0x mx mx m mx 0% mx mx mx 300 HH 0H 0 0 5 0 0 v 0 N H ommHm N .cHeanm asumm cHEan¢ enumm usom mach-Nucmze on nmumHmm 00000 nuuHm-.0H mHmNe 44 v.5N 0.50 vH lull 0.N0 III: 0.00 0H 0.H0 5.00 0.00 H.0N N.00 NH IIII 5.5N 0v 0.0N 0.00 HH 0H VN 00 0.0N 5.0N 0.0H 0H H.0N IIII 0.0N 5.0N 0.N0 H.0N 0.VH 5m 0 a 0.0N H.HN 0.00 0.0N H.0HN IIII v.0N II!- 0 m 0.0H IIII H.0N 5.00 H.50 III: 0.HN IIII 0.0v 5 O 0.0N N.0H N.v0 0.H0 5.5N H.NN 0.0v 0.HN H.0N 0.0V 0 m. 5.00 0.0% 5.00 H.00 0.0N 0.NN 0.0N H.00 0.0N 0.HN mN m 5H N.00 IIII IIII 0.¢N H.0N 0.0N H.00 H.NN 0.NN 0.NN v 0.0H IIII 0.0N 0.00 v.0H 0.0 N.5N 0.00 v.VN 5.0N 0.0N 0 0.0N v.00 0.HN H.00 VH 0.0N 0.00 N.00 H.0N 0.HN 0.5N N 0.NH v.0N H.0H N0 N.0N v.0N N.00 5.5H 0.0N H.vN 5.0V H 0% w mx mx 0x 0 mx 0% mx mx 0% 300 HH 0H 0 0 5 0 0 v 0 N H Owwum w .mcHHnnoHu 05.587002 EH00 .mcHHHfioHo 0025:7002 .5500 .300 How-wucmg 0» wouMHmm nacho fiuHm-IHH wands 45 N.NH -- NH N.NH -- N.0H NH N.NH N.NH H.NH N.NH N.N NH -- N.NH N.NH H.NH N.NH HH N.NH H.NH v.N -- N.NH N.N oH -- N.NH -- N.NH N.NN N.NH N.N N a N.NN N.NH N.NN N.NH N.NN N.NH N.HH N m. -- N.HH N.NH -- -- N.NN -- NH N M N.NH H.NH N.NH N.NH N.NH N.NN N.NH N.NH HN N m. -- H.NH N.NH N.NH N.NH N.NN NN N.NN -- -- N z N.NH -- -- N.NH N.NN N.NH N.NH N.NH N.HN N.NH v -- N.NH N.NN N.NN -- N.NH N.NH N.NN NH N.HN N N.NH N.NH N.HH -- N.NH N.NH «N N.NH N.HH H.NH N N.NH N.NH N.NN H.HN -- N.NN -- -- N.NN N.NH H N Nx mx Nx m ax mx Nx Nx Nx NzoN 0H N N N N N v N N H woman w . 0.3903?» 5500 .cHH500H0-> .5500 9303-039 0» cmuMHmm uwcuo suuHmI-NH wands .cHououm Esuom 0H ucoo M00 cHEan