bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sucking behaviour and serum immunoglobulin levels in neonatal piglets
Authors: de Passillé Anne Marie B. , Rushen J. , Pelletier G. 
Published: September 2010

ABSTRACTThe relationships between the sucking behaviour of newborn piglets during bouts of sucking and their serum immunoglobulin G (IgG) levels at 12 h of age were investigated in 274 Landrace × Yorkshire piglets from 24 second parity Yorkshire sows. Mean IgG level differed between litters but was not related to the number of live-born piglets or the mean birth weight of the litter; in addition, the amount of variation in IgG level within a litter was not related to the number of live-born piglets or the amount of variation in birth weight of the piglets.Within a litter, lower serum IgG levels were found in piglets of birth orders greater than eight and piglets that had a very low frequency of sucking bouts. The piglets that had the higher IgG levels within a litter were those that started to suck sooner, sucked from many teats and won more of their teat disputes. Piglets that were involved in fewer teat disputes within a litter or took a greater proportion of their sucking bouts on anterior teats did not have higher IgG levels. Piglets that died differed from their surviving litter-mates in having lower IgG levels and having lost weight during the first 12 h after birth. Within a litter, IgG levels were not related to 10-day weight gain. However, litters with a lower mean IgG level also had a lower mean 10-day weight gain. It is suggested that a low mean IgG level in a litter reflects or predicts a low milk production by that sow.
Threonine supplementation of diets for pigs between 7 and 56 days of age
Authors: Leibholz Jane 
Published: September 2010

ABSTRACTFifty entire male pigs between 7 and 28 days and 50 entire male pigs between 28 and 56 days of age' were given basal diets containing peanut meal as the protein supplement. These diets contained 4·5 to 6·1 g threonine per kg and were supplemented with graded additions of synthetic L-threonine.It was found that the amount of threonine required for maximum performance and nitrogen retention was 6·6 g/kg dry matter (DM) between 7 and 28 days of age and 5·4 g/kg DM between 28 and 56 days of age. These values were calculated to correspond to 0·43 and 0·36 g threonine per MJ digestible energy.The concentration of threonine in the blood plasma did not give a clear indication of the threonine requirement of the pigs.
Energy and protein utilization of lucerne hay and barley grain by yearling camel calves
Authors: Bhattacharya A. N. , Al-Mutairi S. , Hashimi A. , Economides S. 
Published: September 2010

ABSTRACTTwo trials were conducted with eight yearling camels with an average intial body weight of 300 kg, to evaluate protein and energy values of lucerne hay and barley grains. In each trial, eight animals were randomly allotted to two different dietary treatments of coarsely ground lucerne hay or lucerne hay + barley grain (50:50) in such a way that two animals in each of the two blocks received the same ration. Each trial consisted of a 10-day preliminary period followed by a 7-day collection period during which total urine and faeces collections were made, and samples were processed and composited for later analysis.All animals consumed daily an average of about 5 kg food divided in two equal meals. The apparent digestibility coefficients for organic matter, crude protein, neutral-detergent fibre and cellulose of the lucerne hay ration improved respectively from 0·615, 0·662, 0·455 and 0·555 to 0·736, 0·655, 0·547 and 0·589, as a result of incorporating 500 g/kg barley grain in place of hay in the diet. Even though there was no difference in the proportion of nitrogen retained relative to intake, the proportion of nitrogen retained relative to that absorbed was higher (P < 0·05) in the lucerne + barley group (0·769) than in the lucerne-only group (0·747). On a dry-matter basis, the feeding value in camels of digestible protein (g/kg), total digestible nutrients (g/kg), digestible energy (MJ/kg), metabolizable energy (MJ/kg), net energy maintenance (MJ/kg), net energy lactation (MJ/kg) and net energy gain (MJ/kg) were respectively 118, 552, 10·0, 8·4, 5·4, 5·0 and 2·1 for lucerne hay and 80, 800, 14·6, 12·1, 8·4, 8·8 and 5·0 for barley grain (calculated by difference).
Effects of fish-meal supplementation on performance of overfat lambs fed on barley straw to reduce carcass fatness
Authors: Vipond J. E. , King Margaret E. , Ørskov E. R. , Wetherill G. Z. 
Published: September 2010

ABSTRACTThe effect of undegradable protein supply was studied in overfat lambs given low-energy diets to reduce carcass fatness. Two trials involving sequential batches of 48 overfat Suffolk × lambs investigated the effects of supplementing an ad libitum straw diet with either 0 or 100 g fish-meal pellets daily for 14-, 28- and 42-day periods. Lambs supplemented with fish meal in trials 1 and 2 lost significantly less weight. Weight losses (g/day) were - 2 v. -129 (s.e.d. 26) and -5 8 v. -188 (s.e.d. 29) respectively. There were highly significant and favourable effects of fish-meal supplementation on carcass weight and composition (recorded in the second trial only). Carcass weight (kg) after 14, 28 and 42 days was 21·8, 20·4 and 18·3 for unsupplemented lambs and 22·4, 21·9 and 21·6 for supplemented lambs; saleable lean (kg) as determined by a commercial boning-out process was 12·1, 11·3 and 10·0 v. 12·7, 12·6 and 12·3 respectively. There were corresponding changes in conformation but fat trimmed off the carcass was not significantly reduced by the dietary treatments. There was, however, a reduction by one-fifth in excess carcass fat (about 0·5 kg) over the period 14 to 42 days on trial, and over the trial as a whole, fat trim fell from an estimated proportion of carcass weight of 0·17 to 012, equivalent to a fall in Meat and Livestock Commission fatness score from 4H to 3L. Results indicated very favourable financial rewards for supplementing diets of overfat lambs with fish meal.
Path analysis and robust prediction of lamb carcass composition
Authors: Bennett G. L. 
Published: September 2010

ABSTRACTPath analysis was applied to correlations among lamb carcass measurements. Correlations were obtained from lamb carcasses averaging 15·7 kg and 270 g fat per kg carcass weight. Correlations were adjusted to represent within breed, sex and management group relationships. The purpose of the analysis was to study the relationships of carcass weight with carcass measurements and to identify carcass measurements that are independent other than through their relationships with carcass chemical fat concentration and carcass weight. The direct effect of live weight on all carcass measurements was positive. Thus, heavier carcasses with the same fat concentration had larger fat and tissue depths, muscle measurements, leg measurements and kidney fat weights. The results of correlations among the residuals suggest that fat depths C and J, specific gravity, muscle width A and kidney fat weight are nearly independent estimates of carcass composition in the sense that they are only correlated through their relationships with carcass weight and carcass fat composition. Robust predictors of carcass composition were developed by first adjusting carcass measurements for the direct effects of carcass weight and then computing regressions on the adjusted measurements. These predictors appeared to be better predictors of environmental and genetic differences than least-squares multiple regression yet reduced the accuracy of within group prediction only slightly.
Effect of restricted food intake, before and/or after mating, on the reproductive performance of Greyface ewes
Authors: Rhind S. M. , McKelvey W. A. C. , McMillen S. , Gunn R. G. , Eiston D. A. 
Published: September 2010

ABSTRACTThe effect on the reproductive performance of Greyface (Border Leicester × Scottish Blackface) ewes of a low level food intake and associated loss of live weight from either 14 days before mating, or from the time of mating, until 11 to 26 days after mating, was investigated. Ewes (252) were allocated to one of three treatments with ewes within each treatment divided into two flocks (flock A: 16 ewes per treatment; flock B: 68 ewes per treatment). Ewes of treatment LL were given a ration providing proportionately 0·5 estimated metabolizable energy (ME) requirements for maintenance from 2 weeks before mating. Those of treatment HL were given a daily ration providing 1·5 estimated ME requirements for maintenance until mating and the restricted ration thereafter. Ewes of treatment HH were given the higher ration throughout the experimental period. Flock A ewes were slaughtered at 11 days post mating and flock B ewes at between 18 and 26 days post mating. Treatment differences in the ovulation rates of flock A ewes were not statistically significant but in flock B, ewes of treatment LL had a lower mean ovulation rate (1·81) than those of treatments HL (2·23) and HH (2·09) (P < 0·001). The lower ovulation rate of LL ewes relative to HL ewes in flock B was reflected in a lower mean potential lambing rate per ewe pregnant than in the HL treatment (1·58 v. 1·79; P < 0·01) and per ewe put to the ram (1·37 v. 1·65; P < 0·01). HL ewes had a slightly lower mean potential lambing rate per ewe pregnant (1·79 v. 1·97; P < 01) and per ewe put to the ram (1·65 v. 1·82; P < 0·05) than HH ewes. Ova wastage rates of LL + HL and HH ewes were 0·26 and 014 (P < 001) respectively at 24 days post mating. Values for LL and HL ewes (0·27 and 0·25 respectively) were not significantly different.Estimated mean conceptus lengths were 370, 500 and 1400 μin for LL, HL and HH ewes respectively (P < 0·05).It is concluded that low food intake before mating reduced the mean ovulation rate and low intakes after mating compromised embryo growth rate and induced a higher rate of ova wastage; this increase in the incidence of ova wastage was not significantly exacerbated by the low levels of intake prior to mating.
Digestibilities of nitrogen and amino acids in soya-bean, sunflower, meat and rapeseed meals measured with pigs and poultry
Authors: Green S. , Kiener T. 
Published: September 2010

ABSTRACTIn order to determine the relative digestibilities of nitrogen and amino acids in foodstuffs for pigs and poultry, and the effects of manufacturing methods, equal quantities of soya-bean meal, sunflower meals [hulled (sunflower meal 1) and dehulled (sunflower meal 2)], meat meals [made with (meat meal 1), and without (meat meal 2), blood added at 250 g/kg meat tissue (wet weights)] and rapeseed meals [seeds heated at 80°C (rapeseed meal 1) or 100°C (rapeseed meal 2)] were mixed with protein-free ingredients. The diets were given to five growing pigs with ileo-rectal anastomoses, and, by crop-intubation, to 12 caecectomized and 12 intact cocks. Excreta were collected over 48-h periods. Endogenous excretion was estimated by giving protein-free diets.In the order, soya-bean meal, sunflower meals 1, and 2, meat meals 1, and 2, rapeseed meals 1, and 2, true digestibilities were: with pigs, of nitrogen, 0·81, 0·80, 0·79, 0·64, 0·79, 0·73, 0·70 (s.e.d. 0·030), of lysine, 0·84, 0·83, 0·84, 0·65, 0·84, 0·76, 0·72 (s.e.d. 0·032); with caecectomized birds, of nitrogen, 0·92, 0·91, 0·91, 0·66, 0·78, 0·74, 0·75 (s.e.d. 0·018), of lysine 0·92, 0·91, 0·93, 0·62, 0·79, 0·70, 0·70 (s.e.d. 0·020); with intact birds, values were similar to those with caecectomized birds for soya-bean, and the sunflower meals, but lesser for meat meals 1 and 2; the solubilities of nitrogen in pepsin were 0·96, 0·92, 0·93, 0·80, 0·89, 0·87, 0·87.Two hundred and eighty pigs (initial live weights 10 kg) were used to compare growth response to free lysine with that to lysine in soya-bean meal and sunflower meal 2. Lysine availabilities, assessed by analyses of regressions of live-weight gain against lysine intake were 0·82 (s.e. 0·12) for soya-bean meal, and 0·82 (s.e. 0·18) for sunflower meal 2.Amino acid digestibilities of the sunflower meals were similar to those of soya-bean meal, and were not influenced by dehulling; values for the rapeseed meals were lower, and unaffected by differences in heating severity; values for the meat meal were reduced by blood addition. Values differed between pigs and poultry, but there was consistency in the extent to which each species discriminated between some foodstuffs. The pepsin test was insensitive. The large standard errors associated with availability values prevented meaningful comparisons with digestibility values.
A method to incorporate competitive position in the breeding goal
Authors: de Vries A. G. 
Published: September 2010

ABSTRACTThe value of the improvement of a trait for a breeding organization is determined by its impact on the saleability of its breeding stock. This impact is influenced by the competitive position of the breeding organization, i.e. by the performance of its breeding stock relative to other breeding organizations. A method was developed to take effects of competitive position on the breeding goal into account in designing selection indexes. The main conclusions were as follows.(1) When the performance level of a trait is equal to the average performance level of other breeding organizations, its economic weight (i.e. its weighing factor in the breeding goal) is equal to its importance on a commercial level. With lower performance, the economic weight increases. With higher performance, it decreases.(2) The effect of competitive position on the economic weight of a trait depends on the degree of compensation between traits. When a weakness (negative monetary deviation compared with competitors) n i one trait can be totally compensated by the strength (positive monetary deviation of the same order) i n another trait, then competitive position has no influence on the economic weight.
Carcass and meat quality research to meet market needs
Authors: Kempster A. J. 
Published: September 2010

ABSTRACTThe relationship between carcass and meat quality research and industry requirements is examined with reference to changes in consumer demand.It is argued that much applied research has not focused sharply enough on commercial requirements and that technology transfer has been slow. But there are signs that the pace of future development will be faster, associated with a reorientation of research objectives. The three key factors stimulating change are as follows.(1) Increasing demand by retailers for a consistent product (a demand enforced by the buying power of the major multiple grocers).(2) The reappraisal by breeders of selection objectives.(3) Recent developments in sensor technology and the exploitation of information technology at the producer-processor interface.The implications of each of these are discussed.Driven by these factors research will be targeted increasingly on integrated systems from production to consumption, aimed at specific markets setting different balances between production costs and quality. These will be blueprints for best operating practices and the ‘state of the art’ against which new research developments will be evaluated.Throughout the review, emphasis is placed on the importance of good communication between research workers and industry to confront change and realize the opportunities created.
Operant tests of access to earth as a reinforcement for weaner piglets
Authors: Hutson G. D. 
Published: September 2010

ABSTRACTOperant methods were used to measure the responsiveness to earth of five groups of seven weaner piglets held in a flat-deck cage. Lifts on a lever produced access to an earth trough, an empty trough, or had no effect. Group lever lifting performance was unaffected by earth in the trough, but at least one individual, the ‘worker piglet’, operated the lever more than the others to gain access to earth. Once the lid of the trough was opened other piglets were attracted to the earth and spent more time using the earth trough than the empty trough. Previous experience of earth appeared to modify lever lifting behaviour. In one group, a worker piglet did not emerge, and in another the worker operated the lever for earth at a reduced rate. The number of piglets using the earth trough and the amount of time spent utilizing it was reduced by prior exposure to earth. It is concluded that earth is a mild reinforcer to weaner piglets, that it will sustain a low rate of responding on an operant schedule, and that a component of its reinforcement value is its novelty.
Cloning and genetic improvement of beef cattle
Authors: Smith C. 
Published: September 2010

ABSTRACTCloning of cattle from embryos has been achieved by nuclear transfer. Repeated cloning to produce large clones of genetically identical individuals for commercial use may soon become possible. The main advantage in breeding will come from identifying and using superior clones, selected to fit particular husbandry and marketing niches. Two types of cattle clones will be required, terminal clones chosen for economic merit in production traits, such as growth and carcass traits, and maternal clones chosen for reproduction and maternal traits, such as short calving interval, ease of calving, milking and mothering ability and small mature size. Clonal selection and use will provide several steps of improvement. An initial gain will come by recruiting clones from elite stocks and further responses by selecting the best clones for commercial use. This will reverse the normal improvement lag between breeding and commercial stocks. Heterosis will also be exploited by using crossline clones. For continuous genetic improvement, genetic variation will be maintained by breeding the next generation from a number of selected male and female clones and testing and selecting their progeny, the new set of clones, as before. For maximum improvement rates, both male and female clones will need to be tested. In the short term (5 to 10 years), benefits will come from testing a large number of clones by which gains in economic merit of proportionately 0·15 to 0·30 of the mean can be achieved. Further improvements will come by rebreeding the best clones and testing and selecting the new set of clones from which annual genetic response rates of proportionately 0·02 to 0·03 per year are possible. Cloning thus offers considerable advantages in the improvement of beef cattle.
The effect of avoparcin on the ileal and faecal digestibility of nitrogen and amino acids in the milk-fed calf
Authors: Moughan P. J. , Stevens E. V. J. , Reisima I. D. , Rendel J. 
Published: September 2010

ABSTRACTThe study aimed to determine the effect of the growth promotant avoparcin on the digestion and absorption of nitrogen and amino acids from pre-ruminant milk-fed calves. Eighteen male Friesian calves, 45 kg live weight, were allocated to three diets: a commercial high-quality milk replacer compound (control); control with 100 mg zinc bacitracin per kg (positive control) and control with 40 mg avoparcin per kg. The diets were given once-daily at a set rate of intake during a 14-day metabolic study. On the 15th day the calves were fed at 2-h intervals and ileal digesta were sampled (8 h after the start of feeding) from the euthanazed animal. Estimates of apparent ileal digestibility were determined by reference to an indigestible marker, with the comparable faecal estimates determined following the total collection of faeces.There was no significant effect of avoparcin or zinc bacitracin addition on faecal apparent digestibility of dry matter, nitrogen, gross energy and amino acids or on ileal apparent digestibility of nitrogen and amino acids. Neither was there a significant effect of either additive on nitrogen retention, daily urinary urea and total nitrogen excretions or portal and peripheral plasma urea concentrations. Ileal apparent digestibility coefficients determined on the control diet ranged from 0-82 for glycine to 0-96 for phenylalanine, tyrosine and methionine. The ileal measures of apparent digestibility were more variable than the comparable values determined over the entire digestive tract. Measurements on the faeces compared with measurements on digesta at the terminal ileum gave higher values (P< 0·05) of apparent digestibility for nitrogen and 10 of the 16 amino acids.
Fertility in a tropical beef herd divergently selected for pregnancy rate
Authors: Hetzel D. J. S. , Mackinnon M. J. , Dixon R. , Entwistle K. W. 
Published: September 2010

ABSTRACTSelection on the basis of estimated breeding value for cow fertility was successful in establishing two distinct lines of high (H) and low (L) fertility in a herd of Droughtmaster (Brahman × Shorthorn) cattle. The average difference in pregnancy rates over 3 years between the H and L line was 12% (P < 0·01) in the selected cows. In lactating cows this difference was 17% indicating that lactational anoestrus was an important component of the line difference in fertility. The total calf losses between confirmed pregnancy and weaning were 17%, but there were no line differences. Cow mortalities were 5% higher (P < 0·01) in pregnant cows than in empty cows but were similar in the H and L 'lines.H cows were proportionately 0·06 lighter in body weight (P < 0·01) at mating and 0·075 lighter (P < 0·01) at weaning than L cows. Much of this difference was due to the greater number of calves carried and weaned by H cows during their lifetime. Smaller lactation effects on weight gains and weight losses in H cows indicated that these cows were less sensitive in terms of weight gain to seasonal fluctuations in nutrition. H cows conceived earlier than L cows in 2 out of the 3 years and reared calves which were proportionately 0·04 lighter at weaning (P < 0·01). It is suggested that lower milk production in H cows leading to shorter periods of lactational anoestrous, combined with lower sensitivity to nutritional stress, was responsible for their higher fertility.
Effect of live weight and body composition of gilts at 24 weeks of age on subsequent reproductive efficiency
Authors: King R. H. 
Published: September 2010

ABSTRACTA total of 96 gilts were used in two experiments to determine the effect of live weight and body composition at about 170 days of age on age of attainment of puberty, ovulation rate and subsequent reproductive efficiency.In the first experiment 48 crossbred (Large White ♂ × Landrace ♀) gilts were randomly allocated at 21 days of age to each of six treatment groups which gave six different intakes of a protein-adequate diet. The food intakes were designed to achieve six live weights ranging from 59·6 to 118·0 kg at boar introduction at 170 days of age. Age at puberty declined linearly from 202 to 173 days with increasing live weight at boar introduction (P < 0·01). Ovulation rate at puberty was also positively affected by live weight at 170 days (P < 0·05).In the second experiment, four littermates from each of 12 litters were randomly allocated at 28 days of age to four treatment groups. The groups were offered diets of varying protein adequacy at different feeding levels up to boar introduction at 165 days of age. The treatment groups comprised a factorial design with the factors being live weight (light, L or heavy, H) and fat level (lean, 1 or fat, f relative fat content). At boar introduction, mean live weights were 70·6, 71·5, 101·3 and 100·0 kg, and mean backfat depths were 11·3, 20·9, 21·7 and 27·0 mm for the LI, Lf, HI and Hf groups, respectively. Heavier gilts at boar introduction were younger (183 v. 199 days, P < 0·01) at puberty. Ovulation rate at puberty was also greater (11·0 v. 9·5, P < 0·05) in the heavier gilts. Gilts which were leaner at boar introduction also tended to attain puberty earlier (186 v. 195 days, P < 0·10) than fatter gilts.In both experiments neither the subsequent reproductive efficiency of gilts after parturition nor the performance of their piglets was significantly affected by body weight or body composition at boar introduction.