bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECT OF GROUP SIZE ON OPERANT HEAT DEMAND OF PIGLETS
Authors: MORRISON W. D. , LAFOREST K. L. , McMILLAN I.
Published: March 2010

Eighty newly weaned gilts with an average weight of 7.36 kg were randomly allocated to groups of either two, four, six or eight piglets per pen. The different group sizes were repeated four times. There was no significant difference (P > 0.05) between treatments (group size) for average total weight gain. There was a difference (P < 0.05) between treatments for the average amount of time (min h−1) of operant supplemental infrared heat demanded by the pigs. There was a difference (P < 0.05) in amount of infrared heat demanded during the day (06:00–18:00 h) vs. night (18:00–06:00 h), (19.07 ± 5.17 vs. 11.27 ± 6.01 min h−1, respectively), for the combined group sizes. There was a difference (P < 0.05) between treatments for the number of overall (24 h) rewarded hits. Both diurnal and overall (24 h) rewarded hits had a significant (P < 0.05) linear trend. For each increase of one pig in the group there was a decrease of 1.56 min h−1 of heat demanded by the pigs. The pigs demanded 32–40% of the total amount of supplementary heat at night. Key words: Group size, operant conditioning, piglet
THE INFLUENCE OF ALTERED WEANING MANAGEMENT ON PIGLET GROWTH AND SOW REPRODUCTIVE PERFORMANCE
Authors: GILBERTSON J. , THACKER P. A. , KIRKWOOD R. N.
Published: March 2010

An experiment was undertaken to investigate the influence of split-weaning of litters 7 d before full weaning on the growth of piglets and the reproductive performance of sows. The litters of 27 Yorkshire × Landrace sows were assigned to be either split-weaned (heaviest piglets removed at 21 d of lactation; n = 13) or to act as controls (all piglets weaned at 28 d of lactation; n = 14). The influence on sow and litter performance was monitored. During lactation, mean sow feed intakes in the split-weaned and control groups were 6.9 ± 0.1 and 6.7 ± 0.2 kg d−1, respectively. The diet was formulated to provide 12.3 MJ DE kg−1 and 15.7% crude protein. Nursing piglets were allowed free access to a 20% crude protein creep feed from 7 d of age. Weaned piglets were fed ad libitum a commercial starter diet containing 18% crude protein. Split-weaning had no effect on either the weaning to estrus interval or subsequent litter size (4.5 ± 0.1 vs. 4.3 ± 0.4 d and 12.7 ± 0.9 vs. 13.0 ± 0.9 pigs, for split-weaned and control sows, respectively). However, while control sows lost weight between 21 and 28 d of lactation, the split-weaned sows gained weight (P < 0.02). There was no treatment effect on body weights of nursing piglets but weaning of the heavy piglets at 21 d resulted in a lower (P < 0.05) body weight at 28 d. On days 21 and 28, four sows from each group were blood sampled via indwelling vena caval cannulae at hourly intervals for 10 h. Also, samples were taken every 15 min for 4 h on these days. No treatment effect was noted for mean serum concentrations of luteinizing hormone (LH) or follicle stimulating hormone (FSH). Similarly, there was no effect on LH pulse frequency or amplitude. It is concluded that, in the absence of excessive sow weight loss or prolonged weaning to estrus intervals, the introduction of a split-weaning regime will not enhance sow or litter performance. Key words: Split-weaning, piglet growth, sow performance
THE ACCUMULATIVE EFFECT OF FINNSHEEP BREEDING IN CROSSBREEDING SCHEMES: MARKET LAMB PRODUCTION FROM CROSSBRED EWES
Authors: FAHMY MOHAMED H.
Published: March 2010

Growth and carcass data were collected on 252 multiple-born lambs representing 11 genetic groups, fed either high-energy mainly concentrate ration or low-energy mainly roughage ration and slaughtered at either 32 or 41 kg liveweight. The lambs were the progeny of Suffolk rams mated to Suffolk, Finnsheep (F), DLS (1/2 Dorset, 1/4 Leicester, 1/4 Suffolk) ewes and ewes from seven F-DLS crosses ranging between 1/8F-7/8DLS (1/8F) to 7/8F-1/8DLS (7/8F) in addition to DLS × DLS lambs. The effect of genetic group was significant for gain to 32 kg, dressing percentage, leg, loin, shoulder and kidney fat percentage of the carcass, lean, fat and bone percentage of the 12th rib and fat thickness over the loin-eye muscle. A significant linear relationship was calculated between five of the measurements and the proportion of F breeding in the lambs' dam. Finnsheep ewes produced $6.39 worth of retailed lambs for each kilogram of their liveweight, compared to $3.64 for Suffolks and $3.28 for DLS. The advantage of the F crosses in retail value compared to Suffolk ranged from 47 (7/8F) to 11% (2/8F). Lambs fed concentrate ration and slaughtered at 41 kg liveweight were significantly fatter and larger than those fed roughages and slaughtered at 32 kg. Sex of the lamb had significant effect on all the traits studied except on color, area of loin-eye and carcass dimensions. Interactions between genotype and treatments were generally nonsignificant whereas sex × slaughter weight and sex × feeding treatment were significant on many traits studies. Key words: Finnsheep corsses, growth, carcass traits, DLS sheep, Suffolk, feeding treatment, slaughter weight
THE EFFECT OF PRESLAUGHTER FEED RESTRICTION AND GENOTYPE FOR STRESS SUSCEPTIBILITY ON PORK LEAN QUALITY AND COMPOSITION
Authors: MURRAY A. C. , JONES S. D. M. , SATHER A. P.
Published: March 2010

The effect of the duration of feed restriction prior to slaughter on the ultimate lean meat quality of the longissimus dorsi muscle (loin-eye) was tested in three lines of pigs of differing genotypes with respect to stress susceptibility. Pigs of the Lacombe breed (genotype NN), none of which has been shown to be halothane-positive, yielded a low incidence (0–4%) of pale or soft, exudative pork for all three feed restriction treatments (0,24 and 48 h off feed). The meat quality of pigs from the halothane-positive line (genotype nn) was altered dramatically by the off-feed treatment. The incidence of pale-colored pork decreased from 57% at 0 h off feed to 9% at 48 h off feed, and the incidence of soft, exudative pork decreased from 87% at 0 h off feed to 48% at 48 h off feed. NN × nn crossbred pigs (genotype Nn), all of which gave a negative response to the halothane test, were intermediate in quality between the other two genotypes at all times off feed. In no instance did the feed restriction treatment produce dark, firm, dry (DFD) meat. These data suggest, first, that halothane-negative carriers of the halothane gene may contribute considerably to the incidence of pale, soft, exudative (PSE) pork, and secondly, the manipulation of the length of time of feed prior to shipping for slaughter may offer potential as a management practice to improve meat quality. Key words: Feed restriction, fasting, stress susceptible, quality
ENERGY METABOLISM AND THERMOREGULATION IN THE NEWBORN CALF; VARIATIONS DURING THE FIRST DAY OF LIFE AND DIFFERENCES BETWEEN BREEDS
Authors: VERMOREL M. , VERNET J. , SAIDO  , DARDILLAT C. , DEMIGNE C.
Published: March 2010

Rectal temperature (RT) and heat production (HP) of 10 Holstein–Friesian (HF), 10 Salers (S) and 7 Charolais (CH) calves held in a 10 °C environment were measured continuously during the first day of life. Rectal, skin and haircoat temperature, as well as haircoat weight, were determined in 31 other calves (11 HF, 11 S and 9 CH). Basal metabolism was measured in 18 other newborn calves (9 HF and 9 CH). Heat production decreased curvilinearly and reached a plateau 15 h after birth, when the haircoat was dry. Charolais and Salers calves could maintain their RT in spite of an HP 15 to 10% lower than that of HF calves. This difference could be explained neither by the lower physical activity of CH and S calves nor by better haircoat insulation. It seemed to result mainly from a lower metabolic rate of beef calves, according to the 13% lower basal metabolism of CH calves. These latter were also handicapped by slight acidosis, reduced physical activity, and delayed immunoglobulin absorption, which may contribute to their higher early postnatal mortality and morbidity. Key words: Calf, newborn, breed, energy metabolism, thermoregulation
ENERGY METABOLISM AND THERMOREGULATION IN THE NEWBORN CALF; EFFECT OF CALVING CONDITIONS
Authors: VERMOREL M. , VERNET J. , SAIDO  , DARDILLAT C. , DEMIGNE C. , DAVICCO MARIE-JEANNE
Published: March 2010

Rectal temperature (RT) and heat production (HP) were measured continuously during the first day of life, using indirect calorimetry, in 16 eutocial and 13 dystocial Holstein-Friesian (HF) calves held at 10 °C. Blood parameters were determined 0, 2, 4, 6, 12 and 24 h after birth. Twin eutocial calves, as well as calves born after early surgical removal showed variations in RT, HP, and blood parameters similar to those of single eutocial calves. However, dystocial calves, especially those born after a very difficult and delayed parturition, had severe and prolonged acidosis, with high lactataemia and alaninemia, and lower plasma NEFA, T3, and T4 levels during the first hours of life than did eutocial calves. They were also less physically active and frequently did not shiver. Their HP was, on average, 22% lower than that of eutocial calves 2 h after birth and 14% lower from 13 h of life onwards. The difference was 26–36% in a dystocial calf born after a delayed surgical removal. RT of dystocial calves decreased by 2.9 ± 0.7 °C, on average, and increased slowly. Their appetite was low or nil and immunoglobulin absorption was delayed and reduced, which can explain the high mortality and morbidity rates of dystocial calves during the first week of life. The results are discussed in relation to the effects of hypoxia and acidosis on metabolism. Key words: Calf, newborn, energy metabolism, thermoregulation, calving conditions, dystocia
INFLUENCE OF AMMONIATION OF, HIGH-MOISTURE BARLEY ON DIGESTIBILITY, KINETICS OF RUMEN INGESTA TURNOVER, AND MILK PRODUCTION IN DAIRY COWS
Authors: ROBINSON P. H. , KENNELLY J. J.
Published: March 2010

Three dairy cows with large rumen cannulae were fed totally mixed diets twice daily. Diets contained 49% whole crop oat silage, 38.5% high-moisture barley (HMB), and 12.5% protein-mineral-vitamin supplement on a dry matter (DM) basis. HMB had been ammoniated at target levels of 0, 0.65, 1.30, and 1.95 g per 100 g HMB DM. Actual levels achieved were 0, 0.63, 1.30, and 1.95 g ammonia per 100 g. Apparent digestibility of organic matter (OM), neutral detergent (ND) fiber, starch, and N were not significantly influenced by level of ammoniation of HMB, although there was a trend for increased N digestion. Total rumen pool sizes of wet ingesta and DM were not influenced by ammoniation levels of HMB, although proportion of ND fiber in rumen OM declined as level of ammoniation of HMB increased. Milk yield and production of milk protein and lactose increased as level of ammoniation of HMB increased. Data are interpreted to suggest that rumen digestion of dietary nonfiber components declined as level of ammoniation of HMB increased, although digestion of ND fiber was not influenced. These results support the hypothesis that ammoniation of HMB shifted the site of digestion of a portion of the dietary nonfiber component from the rumen to the intestine without influencing rumen microbial pool sizes or degradative activity. Greater energetic efficiency of intestinal digestion of dietary nonfiber components, as level of ammoniation of HMB increased, may have contributed to the increased milk yield. Key words: Barley (high-moisture), ammoniation, dairy cows, digestion
THE RELATIVE ACCUMULATION OF COPPER IN THE LIVER AND KIDNEYS OF SHEEP FED CORN SILAGE SUPPLEMENTED WITH COPPER CHLORIDE, COPPER ACETATE OR COPPER SULPHATE
Authors: CHARMLEY L. L. , IVAN M.
Published: March 2010

Thirty-two crossbred wethers were used in a randomized block design to study the relative solubility of copper (Cu) in rumen contents and its accumulation in liver and kidneys when fed as three Cu salts, chloride, acetate and sulphate. Cu was added to a corn silage-based diet (containing 6.7 mg Cu kg−1 dry matter (DM)) at a rate of 29 mg Cu kg−1 DM to give a final Cu concentration of 35.7 mg Cu kg−1 DM during an 87-d feeding experiment. Eight sheep were slaughtered at the start of the experiment and the remainder divided between four treatments: control, copper chloride, copper acetate and copper sulphate. Blood samples were taken every 28 d and liver, kidney and rumen content samples taken at slaughter, at the end of the experiment. Liver Cu concentration (mg kg−1 DM) increased from an initial value of 569 to 1174, 1038 and 1050 in the chloride, acetate and sulphate treatments, respectively, and decreased to 512 in the control over 87 d. In the Cu-supplemented wethers, the Cu retained in the liver represented between 1.9 and 2.5% of the Cu ingested. Kidney Cu concentration (mg kg−1 DM) increased from 16 to 114, 59 and 23 in the chloride, acetate and sulphate treatments, respectively, but remained constant in the control. Plasma Cu concentration decreased (P < 0.001) throughout the experiment with the control and sulphate treatments, and remained constant with the chloride and acetate treatments. Plasma ceruloplasmin activity decreased in the control wethers, but remained constant in the other three treatments. Plasma aspartate aminotransferase and diethyl-succinate carboxylesterase activities increased (P < 0.05 and P < 0.01, respectively) in the chloride treatment compared with the acetate and sulphate treatments. The solubility of Cu in rumen contents was 11.1, 13.0, 15.1 and 15.7% in wethers fed the chloride, control, sulphate and acetate diets, respectively. However, the only significant difference occurred between the chloride and acetate groups (P < 0.05). It was concluded that the high dietary levels of copper chloride, acetate or sulphate were equally effective at increasing liver and kidney Cu concentrations in normocupraemic sheep to levels encountered at the haemolytic stage of chronic copper poisoning. Key words: Sheep, copper chloride, copper acetate, copper sulphate, toxicity
EFFECT OF WEIGHT AND FAT COVER ON CHILLING RATE OF CONVENTIONALLY PROCESSED STEER AND HEIFER CARCASSES
Authors: CLIPLEF R. L. , McKAY R. M. , RAHNEFELD G. W.
Published: March 2010

Chill rates over the initial 24 h after slaughter were determined on 382 carcasses (209 steers, 173 heifers) at two anatomical locations (rib and hip) in animals slaughtered at 13.5 and 15.0 mo of age. The objectives of the study were to determine if chill rates differed between steer and heifer carcasses and the influence of hot carcass weight and fat cover on the prediction of chill rate. Steer carcasses chilled at a slower rate than heifer carcasses at the rib location but did not differ in chill rate at the hip location. Both hot carcass weight and fat cover significantly contributed to the determination of chill rate at the rib but only hot carcass weight was important in the determination of chill rate at the hip. At the rib location hot carcass weight had a greater influence than fat cover in accounting for variation in chill rate. The majority of the variation in chill rate at either location was due to factors other than hot carcass weight and fat cover. Key words: Beef carcass, chill rate, carcass weight, fat cover
A STUDY ON THE OCCURRENCE OF COPROPHAGY BEHAVIOR AND ITS RELATIONSHIP TO B-VITAMIN STATUS IN GROWING-FINISHING PIGS
Authors: PASSILLÉ A. M. B. DE , GIRARD C. L. , MATTE J. J. , BILODEAU R. R.
Published: March 2010

Forty-eight 5-wk-old piglets were grouped into six blocks of eight pigs each. Each block comprised two pens of four pigs, two castrates and two females; one pen had solid floor (free access to feces) while the other had slatted floor (limited access to feces). Pigs were fed ad libitum, for 18 wk, a diet computed to meet NRC requirements. At 10, 16 and 22 wk of age, a comparative evaluation of feces intake on each floor type was carried out through utilization of a marker, chromium oxide, in the diet. At the same ages, the behavioral variables — rooting the floor, rooting the walls, rubbing and biting penmates — were recorded during a period of 24 h to evaluate their relationship with weight gain, serum concentrations of folates and vitamin B12. The results showed that there was no effect (P > 0.09) of floor type on ingestion of feces. However, this last variable changed with age, a limited ingestion of feces occurring at 10 wk of age while there was no apparent excrement intake at 16 or 22 wk. Some of the behavior variables permitting feces ingestion were related to weight gain or concentrations of vitamin B12 but the R2 values were small (<0.35). Therefore, it seems that pigs do not ingest significant amounts of feces and that the nutritional contribution of the coprophagy behaviors studied would not be important. Key words: Pigs, floor type, feces intake, behavior, vitamin B status
REPEATABILITY OF OVULATION RATE, NUMBER OF LAMBS BORN AND OVA LOSS IN SHEEP WITH DIFFERENT OVULATION RATES
Authors: FAHMY M. H.
Published: March 2010

Ovulation and lambing records of 214 ewes from nine genetic groups varying in ovulation rate (OR) from 1.8 to 3.2 corpora lutea (CL) and number of lambs born (LB) from 1.2 to 2.1 were analyzed to study the relation between OR, LB, ova loss (OL) and their repeatabilities. The nine genetic groups were DLS, Finnsheep (F) and seven crosses from these two breeds ranging from 1/8 to 7/8 Finnsheep breeding. Intrayear repeatability of OR averaged 0.59 for all genetic groups combined. It ranged from −0.20 for DLS to 0.93 for 5/8 F. Interyear repeatability averaged 0.38 and ranged from 0 for DLS to 0.54 for 3/8 F. OR showed a linear increase (b = 0.22 ± 0.02) with increase in Finnsheep breeding whereas repeatabilities showed a significant quadratic relationship. Repeatability of OR was more associated with variability than with mean OR. Repeatability of OR for ewes which had 1, 2, 3 or 4 CL at first record and averaged 2.3 ± 0.5,2.5 ± 0.7,3.4 ± 1.0 and 3.4 ± 1.3 CL at the following two records was, −0.09, 0.33, 0.42 and 0.42, respectively. Lambs born increased with the increase in Finnsheep breeding from 1.2 for DLS to 2.1 for Finnsheep. Ova loss averaged 35% and was fairly constant in the different genetic groups. Repeatabilities for LB and OL for each genetic group were generally small and mostly nonsignificantly different from zero. For the genetic groups combined the estimates were 0.15 and 0.14 for LB and OL, respectively. The correlation between OR and LB (0.25) was lower than that between OR and OL (0.58) and LB and EM (−0.62). Key words: Ovulation rate, litter size, ova loss, repeatability, Finnsheep crosses, DLS sheep
HIGH-ROUGHAGE RATIONS WITH OR WITHOUT MONENSIN FOR VEAL PRODUCTION. II. RATION DIGESTIBILITY
Authors: POMAR C. , BERNIER J. F. , SEOANE J. R. , LATRILLE L.
Published: March 2010

Thirty-six calves 19–20 wk old (149 ± 17 kg) and forty-eight rams (46 ± 4 kg) were used in two experiments to study the effects of two ground roughages (alfalfa and timothy), their proportion in pelleted rations (20, 40 and 60%) and addition of monensin (0 and 33 ppm) on ration digestibility. Calves and rams were fed the test rations ad libitum for a period of 8 and 5 wk, respectively, before the digestibility trial. Dry matter (DM) digestibility in both species and energy digestibility in calves were significantly higher for the rations containing alfalfa than for those containing timothy; however, digestibility of crude protein (CP) in both animal species and of cell walls (NDF) in calves was lower in alfalfa rations. The two trials revealed an increase in digestibility of acid detergent fiber (ADF) and of cell wall (NDF) fractions but a reduction in DM digestibility when the roughage content in the rations increased; the reduction in DM digestibility was larger with timothy than with alfalfa. Addition of monensin did not affect digestion coefficients of DM, ADF and NDF in calves and rams on average. However, a monensin × roughage level interaction indicated a decrease of ADF and NDF digestibility in calves fed 20% roughage and an increase of ADF and NDF digestibility in calves fed 60% roughage. Key words: Alfalfa, timothy roughage level, monensin, calf, sheep
PERFORMANCE OF LEGHORN PULLETS AND LAYING HENS IN RELATION TO HATCHING EGG SIZE
Authors: LEESON S. , SUMMERS J. D.
Published: March 2010

In trial 1, eggs from young (28 wk) and old (65 wk) leghorn breeders were categorized into groups with mean weights of 54, 59 or 64 g. Female chicks were cage-reared to 18 wk of age; three rearing treatments involved five replicate cages of nine pullets from each egg size category, while treatment 4 involved a mixed population. The largest eggs contained most yolk fat and protein and albumen protein (P < 0.05). Egg size had no effect on male chick composition (P < 0.05). There was no overall effect of egg size or breeder age on feed intake of pullets, although up to 8 wk of age, pullets from small eggs were consistently smaller than those from large eggs. Egg size and breeder flock age had no effect on pullet weight at 18 wk. Pullets reared as a combination group of small:medium:large (3:3:3, treatment 4) showed a significant (P < 0.05) egg size effect on pullet weight at 18 wk of age. In a second trial, eggs were collected from a 45-wk-old flock of commercial leghorn breeders. Eggs were set according to weight, with mean egg weights of 56.4, 61.1 or 66.8 g. Rearing treatments related to the three egg size categories were represented by 10 replicate groups of nine birds each. A fourth treatment involved 26 groups of three chicks from each of the egg weight treatments. Breeder egg size had a significant effect on pullet weight at 126 d. With this differential maintained through the first 12 wk of lay. Breeder egg size had no effect on egg production (P > 0.05), although mean commercial egg weight and feed intake (P < 0.01) were directly proportional to hatching egg size (P < 0.01). It is concluded that hatching egg size can have a significant effect on life-cycle performance of leghorns, and as such, there may be scope for differential management of pullets hatched from different sizes of egg. Key words: Pullet, egg size, egg composition
THE EFFECT OF ADJUSTING FOR YEARLY SELECTION TRENDS ON VARIANCE COMPONENT ESTIMATES
Authors: GEARHEART W. W. , DAVIS M. E. , HARVEY W. R.
Published: March 2010

Computer-generated beef cattle data were used to investigate the effect of accounting for the yearly selection of parents on the bias and precision of sire and error variance component estimates. The adjustment for yearly selection reduced the biases of estimated sire variance components, but resulted in losses of precision of up to 25%. Key words: Beef cattle, variance component, selection
EFFECT OF DIETARY TAURINE SUPPLEMENTATION ON SUDDEN DEATH SYNDROME IN BROILER CHICKENS
Authors: CAMPBELL G. L. , CLASSEN H. L.
Published: March 2010

Dietary taurine supplementation (0, 0.05, 0.10, or 0.20%) was examined as a means of reducing sudden death syndrome (SDS) in male broiler chickens (624 per treatment) raised to market weight. Total mortality and sudden death syndrome were lower for broilers fed taurine-supplemented diets. The feed-to-gain ratio from 3 to 6 wk decreased linearly with increasing dietary taurine while taurine addition had no effect on 3-wk or 6-wk body weight, or feed-to-gain ratio from 0 to 3 wk. Key words: Sudden death syndrome, taurine, broiler chickens
THE DISTRIBUTION OF TRYPSIN AND CHYMOTRYPSIN INHIBITORS IN POTATO TUBERS
Authors: NICHOLSON J. W. G. , ALLEN J. G.
Published: March 2010

Potato peel contains trypsin and chymotrypsin inhibitors at levels similar to those in other parts of the tuber. The levels of these inhibitors differ among potato cultivars (P < 0.01). The proteolytic enzyme inhibitors may have to be deactiviated before peel waste can be efficiently utilized by pigs. Key words: Potato steam peel, trypsin, chymotrypsin, proteolytic enzyme inhibitor
A METHOD FOR INTRODUCING PIGS INTO FREE-ACCESS TWO-LEVEL PENS
Authors: FRASER DAVID , PHILLIPS P. A.
Published: March 2010

Groups of 12 grower pigs were housed in a two-level pen in which a short ramp gave access to an upper level for feeding and resting. Two experiments studied the behavior and performance of pigs when introduced into the pens in two different ways. Twelve groups were herded into the lower floor and were allowed to climb the ramp at will. Most did so, but 12 of the 144 animals had to be forced up the ramp the first time. Compared to matched groups in conventional pens, pigs in the two-level pens ate 9.5% less feed in the first 3 d (P < 0.01) and gained 0.5 kg less weight in the first week (P < 0.025). Twelve other groups were driven directly up the ramp and were confined on the upper level for the first 3 d, with the ramp pinned in a horizontal position to form a temporary dunging area. With this procedure there was no initial depression of feed intake, little effect on initial weight gain, no need for the manager to identify "ramp-shy" pigs, and little accumulation of manure on the upper level. The procedure is recommended for introducing pigs into two-level pens. Key words: Pigs, pen design, weight gain, feed consumption, animal welfare
USING EARLY SUCKLING BEHAVIOR AND WEIGHT GAIN TO IDENTIFY PIGLETS AT RISK
Authors: de PASSILLÉ ANNE MARIE B. , RUSHEN JEFFREY
Published: March 2010

We examined whether characteristics and behavior of the newborn piglet could be used to identify later mortality and poor growth. Thirty-seven litters were classified as having no mortality (n = 12), low mortality (one or two deaths, n = 17) or high mortality (three or more deaths, n = 8). The eight high-mortality litters accounted for 61% of the deaths. Starvation was the most common cause of death in the high-mortality litters while other causes predominated in low-mortality litters. The mortality in a litter was correlated with 3-d weight gain of the survivors suggesting that low milk production by the sow was a major cause of death. During the first 10 h of litter age, teat disputes were more frequent, total time fighting was longer, and synchrony between piglets in suckling developed more slowly in the high-mortality litters. Piglets that died did not differ from the surviving piglets in birth order. However, they tended to have lower birth weights, suckled less often, suckled fewer teats, took a larger proportion of their suckling bouts on the three anterior teat pairs, and were less successful in teat disputes. Piglets that had poor 10-d gains tended to spend a long time fighting, won few teat disputes and suckled less frequently during the first hours after birth, but the correlations were small. Thus, high-mortality litters can be identified before deaths occur. Early identification will improve the efficiency of management programs such as attendance at farrowing and early intervention and thus increase the survival and well-being of piglets. Key words: Neonatal piglet, suckling behavior, teat disputes, mortality, weight gain
PARTITIONING AND DISTRIBUTION OF ADIPOSE TISSUE AND LIPID IN MICE SELECTED FOR HIGH BODY WEIGHT
Authors: SALMON R. KEITH , BERG ROY T.
Published: March 2010

To elucidate the influence of high body weight selection on the specific pattern of fat partitioning and distribution within the mouse, depot adipose tissue and depot lipid, relative to total depot adipose tissue and total depot lipid, were investigated in both a line of mice selected for high 42-d body weight (High line; HL-3) and an unselected foundation (FP-3) population. Dissectable adipose tissue depots were identified in five anatomical locations within the mice. Employing the allometric equation, Y = aXb, this investigation revealed that the selection pressure had very limited influence upon the developmental relationships among the various depots. However, in comparison with FP-3 males, HL-3 males did appear to partition more fat into the kidney depot, and less into the hindlimb depot, over the range of common total fat weight. Within females, with the exception of minor differences in the relative growth of forelimb fat, no obvious line differences existed in either the partitioning or distribution of fat. Thus, high body weight selection pressure had limited influence upon the developmental relationships among the various depots. Key words: Growth-selected mice, adipose tissue depots, fat partitioning, fat distribution
CARCASS AND EMPTY BODY COMPOSITION OF HEREFORD AND ANGUS BULLS FROM LINES SELECTED FOR RAPID GROWTH ON HIGH-ENERGY OR LOW-ENERGY DEITS
Authors: BAILEY C. B. , LAWSON J. E.
Published: March 2010

Hereford and Angus bull calves, progeny of breeding lines selected for nearly six generations for rapid growth on a high-energy (80% concentrate: 20% forage) or a low-energy (100% forage) diet, were themselves given a diet of 70% concentrate: 30% forage from 50 kg liveweight until slaughter at 500 kg liveweight. Effects of breed and ancestral selection diet on the composition of the empty body and the carcass at slaughter were measured. The sole effect of differences in the energy content of the selection diet was that bulls from the high-energy selection lines had higher proportions of muscle and bone in the front quarter and lower proportions in the hind quarter than bulls from the low-energy selection lines. Differences were small and probably not of economic importance. Breed of bull influenced significantly a number of body composition variables. As a proportion of empty liveweight, Herefords had lighter carcasses, less kidney fat, and heavier hides, heads, and feet than Angus. In addition, the carcasses of Hereford bulls had a higher proportion of bone than did those of the Angus and this was associated with differences in live body dimensions that reflected a larger overall skeletal size. As a result of these differences in the distribution of weight among the various parts of the empty body, Angus were superior to the Herefords in terms of total yield of carcass muscle (642 vs. 616 g kg−1 of empty liveweight) and ratio of muscle to bone in the carcass (4.96 vs. 4.64). It was concluded that the various indices of empty body and carcass composition were little influenced by ancestral selection diet but were affected by breed. Key words: Carcass, empty body, composition, cattle, selection, growth rate
BREED STRUCTURE OF PEDIGREED HEREFORD CATTLE IN CANADA
Authors: KOOTS K. R. , CROW G. H.
Published: March 2010

A study of the Canadian pedigreed Hereford cattle population was carried out to determine breed structure and to determine if interherd selection decisions were related to measures of performance. The group of calves born in 1982 (N = 53 352) was the reference population for this study. There was a clear subdivision of the pedigreed population according to the horned-polled status of individuals. 52.54% of calves were phenotypically polled calves with both parents polled, 41.82% of calves were horned calves with both parents horned; the remaining calves were the result of mating parents of different horned-polled phenotype or were different in phenotype from their parents. There appeared to be a very high level of interherd transferrals of parents: in herds registering fewer than 10 calves only 5.38% of sires and 31.68% of dams were homebred. In herds registering larger numbers of calves more parents were home-bred. A hierarchy among herds was found to exist in each of the horned and polled subpopulations with three strata in the horned group, two strata in the polled group, and a relatively small effective number of primary (or "nucleus") breeders' herds in both cases. The association between popularity of a herd (denoted as the number of herds to which sires were transferred) and herd average sire proofs for calving ease, preweaning gain and gain from birth to yearling age was evaluated using multiple regression (R2 = 3.45). Only average calving ease proof of a herd had any significant (P < 0.05) association with herd popularity. Higher average calving ease proof for a herd was associated with higher popularity of a herd, but only up to a point since the regression was quadratic. Key words: Beef cattle, breed structure, Hereford, genetics
THE EFFECT OF SHACKLING ON PORK QUALITY FROM PIGS OF DIFFERENT GENOTYPES
Authors: GARIEPY C. , JONES S. D. M. , MURRAY A. C. , ROBERTSON W. M.
Published: March 2010

Over a 3-yr period, two experiments were conducted on 465 pigs to evaluate the effect of genetic line and shackling on pork muscle quality. In exp. 1, 343 gilts and barrows of two stress-resistant genotypes (Lacombe and Yorkshire) were compared for 45 min pH and temperature (To), and ultimate meat quality. In exp. 2, 102 gilts and barrows of a stress-susceptible (Halothane+/+), a stress-resistant (Halothane−/−) and a heterozygous genotype (Halothane+/−), were compared for the same parameters. In both experiments, following electrical stunning (head to back; 400 V, 1.7 A), pigs were shackled by alternate hind legs for 3–4 min including bleeding time. Color, pH, percent drip loss, percent expressible juice, percent soluble protein, shear force measurements, as well as subjective evaluation of color and structure were performed for the midsection of the longissimus muscle. Results of exp. 1 showed that Lacombe pigs produced meat with significantly higher processing attributes (lower drip loss and expressible juice, higher soluble protein) and lower shear force values than Yorkshire pigs. Shackling had no significant effect on longissimus muscle quality. In exp. 2, genetic line had a significant effect on pork quality. Although shackling showed significant interaction with sex on 45-min measurements for pH and To, shackling was found to have little effect on ultimate meat quality. It was concluded that genotype had a major influence and shackling had a very minor influence on longissimus muscle quality. Key words: Pig, shackling, meat quality, stress susceptibility
THE PREDICTION OF BEEF CARCASS LEAN CONTENT BY AN ELECTRONIC PROBE, A VISUAL SCORING SYSTEM AND CARCASS MEASUREMENTS
Authors: JONES S. D. M. , TONG A. K. W. , ROBERTSON W. M.
Published: March 2010

Five hundred and thirty-one beef carcasses were used to establish if Hennessy Grading Probe (HGP) measurements provided a more accurate assessment of carcass lean content than a visual scoring system or linear carcass measurements. Carcasses were probed at the 5th/6th, 11th/12th, 12th/13th ribs, 2nd/3rd lumbar and sacral crest position (P8). Carcasses were then visually appraised for overall fat cover and muscle thickness. Following 24 h of cooling, the measurements by HGP and visual scores were repeated. Fat thickness and loin eye area were recorded at the 12th rib. Precision for the prediction of carcass lean by HGP was similar in warm or cold carcasses and the lowest error of prediction for the probe was associated with measurements made at the 12th/13th rib (RSD 31.8 g kg−1). A combined visual score for overall fat cover and muscle thickness was more precise (RSD 28.6 g kg−1) than probe measurements for predicting lean yield in warm and cold carcasses. Canada grade had the lowest precision (RSD 34.7 g kg−1) for predicting lean yield, but measurements of average fat thickness and loin eye area at the 12th rib gave the best overall prediction (RSD 27.1 g kg−1) of carcass lean content. It was concluded that the HGP provided a method to classify warm carcasses for lean content, but the improvement in precision over conventional grading procedures was not large. Key words: Beef, carcass, grading, Hennessy grading probe, composition
FACTORS INFLUENCING THE COMMERCIAL INCIDENCE OF DARK CUTTING BEEF
Authors: JONES S. D. M. , TONG A. K. W.
Published: March 2010

Data collected on 170 534 head of Saskatchewan cattle slaughtered over a period of 12 consecutive months were used to evaluate the importance of some factors influencing the incidence of dark cutting (DC) beef (Canada B2 grade based on a visual assessment of muscle color and texture). The variables examined included carcass weight, gender of animal, daily temperature and precipitation, month of slaughter, distance from farm to abattoir, mixing of loads during transportation and slaughter plant. DC beef compared to normal beef was associated with a slightly warmer daily temperature (5.4 vs. 4.8 °C), a lighter carcass weight (283 vs. 286 kg), but was not influenced by daily precipitation. The incidence of DC beef increased as distance between farm and slaughter plant increased (0.78–0.98%), and was higher in loads of cattle that were mixed during transportation than in those loads that originated from the same farm (1.11 vs. 0.79%). Steers recorded a higher frequency of DC beef than heifers (0.99 vs. 0.77%). There were large differences in the frequency of DC beef among slaughter plants after adjustment of the data for the effects of other variables (gender, mixing, trucking distance). Of the six slaughter plants in this study, the frequency of DC beef ranged from 0.27–1.79%. Month of shipment had a significant effect on the incidence of DB beef, with March and April recording the highest frequencies (1.54 and 1.24%), and December the lowest (0.45%). It was concluded that the mixing of loads and the slaughter plant were the two most important predisposing factors for DC beef. Key words: Beef, carcass, stress, dark cutting
EFFECT OF THE STRESS OF INJECTIONS ON THE SERUM CONCENTRATION OF CORTISOL, PROLACTIN, AND GROWTH HORMONE IN GILTS AND LACTATING SOWS
Authors: ROBERT S. , PASSILLÉ A.-M. B. DE , ST-PIERRE N. , PELLETIER G. , PETITCLERC D. , DUBREUIL P. , BRAZEAU P.
Published: March 2010

Three experiments were conducted to determine the effect of subcutaneous injections of saline on serum concentrations of cortisol, prolactin and growth hormone in cycling gilts and lactating sows. In exp. 1, five crossbred cycling gilts were given one subcutaneous injection and blood was sampled during the preceding and following four hours. In exp. 2, blood samples were taken from six purebred lactating sows on a control day and on a day when they were injected with saline in a latin square design. Serum concentrations of cortisol, prolactin and growth hormone were monitored in exps. 1 and 2. In exp. 3, 11 purebred primiparous sows received subcutaneous injections twice daily from 5 to 25 d postpartum. Blood samples were collected for cortisol assay on days 5, 15 and 25. Serum cortisol concentrations increased significantly after saline injection in the three experiments, confirming that injections cause a stimulation of the hypothalamic-hypophyseal-adrenal axis in cycling gilts and lactating sows. When additional stressors such as handling and physical restraint were imposed prior to the injection, a release of prolactin and growth hormone was also observed in cycling gilts. The serum cortisol profiles of lactating sows repeatedly injected showed that their cortisol response to subcutaneous injections attenuated over days. Furthermore, these data indicate that the animals became readily acclimated to blood collection from a catheter within the first day of sampling. Key words: Cortisol, prolactin, growth hormone, stress, gilts, lactating sows
STUDIES ON THE FEEDING VALUE OF Kochia scoparia (L.) Schrad. HAY FOR BEEF CATTLE
Authors: COHEN R. D. H. , IWAASA A. D. , MANN M. E. , COXWORTH E. , KERNAN J. A.
Published: March 2010

Intake, digestibility, nitrogen retention and the effects of 2.6% soluble oxalates in the dry matter (DM) of kochia (Kochia scoparia (L.) Schrad.) were examined when beef steers were fed rations varying from 100 to 0% kochia hay and 100 - 0% bromegrass (Bromus inermis Lyess.)/alfalfa (Medicago sativa L.) hay. Plasma Ca, P, Mg, Zn, Fe and Cu concentrations were normal and not affected by supplementation with CaCO3. The organic matter digestibility (OMD) of kochia (55.4%) was less (P < 0.05) than that of the bromegrass/alfalfa hay (61.3%). However, in a second trial, OMD was not influenced if kochia was included at up to 60% of the ration. In a third trial, DM intake remained constant until 60% kochia was present in the ration but was reduced (P < 0.01), even with careful adaptation, when kochia exceeded 60% of the diet. Nitrogen retention declined (P < 0.05) as the proportion of kochia in the ration increased and was negligible at 100% kochia. Key words: Kochia, digestibility, intake, nitrogen retention, plasma minerals, cattle (beef)
NAKED OATS (Avena nuda) WITH AND WITHOUT LYSINE SUPPLEMENTATION, FOR BOARS AND BARROWS: GROWTH, CARCASS AND MEAT QUALITY, ENERGY AND NITROGEN METABOLISM
Authors: FRIEND D. W. , FORTIN A. , KRAMER J. K. G. , BUTLER G. , POSTE L. M. , BURROWS V. D.
Published: March 2010

Thirty-six boars and 36 barrows were fed four diets. The control was a fortified corn-soybean meal diet. Diets 50 L and 100 L were lysine-supplemented, and 48% and 95%, respectively, of the corn and soybean meal were replaced by Tibor naked oats. Diet 100 (unsupplemented) contained 95% naked oats. The diets were pelleted and given ad libitum to pigs housed three per pen. At a slaughter liveweight of approximately 90 kg, the left side of the carcass was used for carcass and meat quality examinations and samples were taken for fatty acid (FA) analysis. Additionally, 24 boars and 24 barrows were fed the four diets in a metabolism trial to determine metabolizable energy and nitrogen values. Daily gain by pigs fed Diet 100 was less (P < 0.01), and their times to market weight were 10 and 8 d longer, respectively, than pigs fed Diets 50 L and 100 L. Boars ate significantly less feed daily than barrows, and the rate of gain for boars was less and feed efficiency higher than for barrows. Total yield of lean meat was less (P < 0.05) from Diet 100 pigs than from those fed the other diets. The carcass index was higher (P < 0.05) for boars (106) than for barrows (102). The FA profile for the Tibor naked oats was very similar to that reported in a previous study even though the two crops were grown on different farms and 1 yr apart. Naked oats increased significantly the concentration of 18:1n–9 and 20:1 in the carcass backfat, but did not influence the quality of the loin muscle fat. An increased (P < 0.05) intensity of flavor in the pork loin roasts was associated with the naked oats diets. Boar roasts scored higher (P < 0.05) for juiciness than those from barrows; there was no difference in boar taint between the two sexes. The metabolizable energy value of the control diet was higher than those of the oats diets; significantly higher when corrected for N retained. Pigs fed Diet 100 L retained (P < 0.05) the most N (18.7 g d−1) and Diet 100 the least (15.8 g d−1). Nitrogen retention as a proportion of N intake was more (P < 0.05) for boars than for barrows. This study supported the inclusion of at least 48% naked oats in a diet for growing-finishing pigs. Key words: Boars, oats (naked), metabolism, carcass, fatty acids, meat quality
EFFECTS OF FLOOR TYPE ON SERUM FOLATES, SERUM VITAMIN B12, PLASMA BIOTIN AND ON GROWTH PERFORMANCES OF PIGS
Authors: BILODEAU R. , BRISSON G. J. , MATTE J. J. , PASSILLÉ A. M. B. de , GIRARD C. L.
Published: March 2010

Forty-eight 5-wk-old piglets were grouped into six blocks of eight pigs each. Each block comprised two pens of four pigs, two castrates and two females; one pen had a solid floor (free access to feces) while the other had a slatted floor (limited access to feces). Pigs were fed ad libitum a diet computed to meet NRC requirements for 18 wk. Every 14 d, each animal was weighed and a blood sample was taken for the determination of folates, vitamin B12, biotin, hemoglobin (Hb) and hematocrit (Ht) levels. There was no effect (P > 0.05) of floor type on serum folates or vitamin B12, nor on plasma biotin which averaged, respectively, 72.2 ± 2.9 ng mL−1, 246.0 ± 21.3 pg mL−1 and 1.34 ± 0.1 ng mL−1 at the end of the experiment. Biotin concentration was about 16-fold greater in the feces than in the diet, which was indicative of active bacterial synthesis of B-complex vitamins in the gut. Hb and Ht were about 4% higher (P < 0.05) in pigs on slatted floors than in those on solid floors. From 5 to 11 wk, pigs raised on slatted floors grew faster (P < 0.05) than those raised on solid floors, but growth rate was similar (P > 0.05) on both floor types from 11 to 23 wk. The results suggest that whatever the age of growing pigs, coprophagy is not an important way by which these animals meet their requirements in B-complex vitamins. Key words: Pigs, floor type, coprophagy, folates, vitamin B12, biotin
A REPEATABLE VENOUS CATHETERIZATION TECHNIQUE FOR SERIAL BLOOD SAMPLING IN GROWING SWINE
Authors: KARALUS URSULA , DOWNEY BRUCE R.
Published: March 2010

A technique is described in which an indwelling vinyl catheter was placed into the anterior vena cava of growing gilts via the jugular vein, threaded through subcutaneous tissue, and exteriorized on the dorsal surface of the neck. Functional for 6 d or more, the catheter was removed nonsurgically without apparent vascular damage and new catheters were installed 30 and 60 d later in the same animals. Repeated serial blood samplings were possible without maintaining long-term chronic catheters in place and with the animals having unrestricted movement in individual pens. Key words: Catheter, vein, swine
THE INFLUENCE OF SEX AND BIRTH WEIGHT OF THE CALF AND THE PARITY AND LENGTH OF GESTATION ON THE TIME OF CALVING
Authors: THARMARAJ J. , SHINDE Y. , KASHIWAMURA F. , NAKAMURA M. , IKETAKI T. , OTA S.
Published: March 2010

Data on 721 calvings of Holstein cows recorded over a 10-yr period at the Obihiro University Dairy Farm were analyzed using chi-square analysis of variance. Calvings were not evenly distributed over the 24 h (P < 0.05). Calf birth weight affected the time of calving (P = 0.02). Sex of the calf (P = 0.73), parity (P = 0.55) and length of gestation (P = 0.10) did not directly influence the time of calving. Calves were divided into three groups according to their birth weights, within subclasses of sex (male, female), parity (early, late) and length of gestation (short, long). The groups were: light weight (≤ mean − SD under that subclass), average (mean + SD) and heavy (≥ mean + SD). Chi-square analysis comparing the three birth weight groups revealed that most of the lightest calves were born during the night. Weight of the mature fetus was related to the time of calving, but the mechanism for it was not resolved. Key words: Calving time, calf birth weight, parturition
FEED EFFICIENCY OF DAIRY COWS DURING FIRST LACTATION
Authors: LEE A. J. , SLIGER L. A. , LIN C. Y. , McALLISTER A. J. , BATRA T. R. , ROY G. L. , VESELY J. A. , WAUTHY J. M. , WINTER K. A.
Published: March 2010

Feed efficiency was examined from approximately 3200 records of feed intake, milk yield, weight and weight change during the second eight weeks of first lactation on Holstein (H line), Ayrshire based (A line) and crossbred (C line) cattle. Herd, year-season and age at first calving with either genetic line or original breed source additive, heterotic and maternal effects were included in models. Heterotic and maternal effects on milk yield, TDN consumption and feed efficiency were generally unimportant when initial weight, weight change and milk yield or TDN covariates were considered. Line (A, H and C) and breed source additive effects within line were generally significant (P < 0.05). Efficiency was highly correlated phenotypically (0.64) with milk yield but only mildly correlated with measures of feed intake (0.13, 0.38). The negative correlation of efficiency with initial weight (−0.13) and weight change during the trial (−0.15) indicated that the larger animals or animals which gained more weight use a higher proportion of feed energy for maintenance requirements and growth than lighter animals. The strong correlations (0.63, 0.81) between milk yield and consumption arose in part from feeding concentrates according to milk production and made appropriate analyses difficult. Adjusted for covariates, Canadian (CH) and American (USH) Holsteins were the highest producers followed by Norwegian Red (NR), Agriculture Canada Holsteins (ACH), Ayrshires and Brown Swiss. North American Ayrshires (NAA) consumed the least TDN, adjusted for covariates, with Holsteins intermediate and Brown Swiss highest. In general, Ayrshires were more efficient than Holsteins. Feed efficiencies of NAA, Finnish Ayrshire and NR were superior to those of ACH with other genetic groups intermediate. Key words: Genetic, feed efficiency, lactation, cattle