bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crossbreeding beef cattle in Western Uganda. 2. Environmental influences on body weight
Authors: Sacker G. D. , Trail J. C. M. , Fisher I. L. 
Published: September 2010

SUMMARYThe nine possible breed types resulting from the use of Angus, Boran and Red Poll bulls on Ankole, Boran and local Zebu cows were represented in the experiment. Sex, period of birth and year of birth had significant effects, at practically all ages, on body weights of calves measured at three-monthly intervals from birth to two years. Age of dam had a significant effect on calf weight at birth but not thereafter. Previous parous state of dam had only few apparently significant effects on calf weights at different ages. It appeared that beneficial effects of a good pre-weaning maternal environment might be retained, as there was no strong evidence of post-weaning compensatory growth for pre-weaning maternal effects due to age and previous parous state of dam.
The nutritive value of separated milk for pigs. III. A note on the effects of supplementary lysine and methionine on performance to 55 kg live weight
Authors: Chamberlain A. G. , Cooke B. C. 
Published: September 2010

SUMMARYAttempts were made to improve the nutritive value of diets based on separated milk and barley by adding free lysine and methionine. Feeding trial and nitrogen metabolism studies showed small beneficial responses to lysine, but not to methionine; the effects however were not statistically significant.
Moist barley preserved with acid in the diet of the growing pig
Authors: Perez-Aleman S. , Dempster D. G. , English P. R. , Topps J. H. 
Published: September 2010

SUMMARYThe feeding value of moist barley (approximately 27% moisture) which had been treated with 1·3 % of a mixture of formic (70 %) and propionic (30 %) acids was compared with that of dried barley for growing pigs from 23 to 85 kg live weight. Two experiments were undertaken; 96 pigs were fed ad libitum on one of three diets containing dried or acid-treated moist barley and another 48 pigs were individually fed on one of four diets containing dried or acid-treated moist barley in controlled amounts. These amounts were governed by an allowance of dry matter at a certain live weight.In neither experiment were significant differences found between the treatments in growth rate or efficiency of utilization of food dry matter. Pigs fed ad libitum showed no significant difference in intake of dry matter, but those given the diet containing dried barley had a higher content of fat in their carcass than those on the acid-treated barley. A total of 21 pigs, 16 fed ad libitum and all receiving diets containing acid-treated barley had a discolouration of fat in the carcass.
The influence of environmental temperature and plane of nutrition on heat losses from individual pigs
Authors: Close W. H. 
Published: September 2010

SUMMARY1. The total rate of heat loss from individual pigs (20 to 40 kg body weight) was measured over 6-hr periods in a small heat sink calorimeter at 7°, 20° and 30°C, with feeding levels of 34, 39, 45 and 52 g/kg body weight per day.2. Total heat loss at 7°C was significantly greater than at 20° or 30°C; there was no significant difference in heat loss between temperatures of 20° and 30°C.3. Heat loss per m2 of body surface was independent of feeding level at 7°C. At 20°C, heat loss on the high feeding level was significantly greater than that on the low level, and at 30°C heat loss on both the low and medium feeding levels was significantly greater than that on the very low level.
A note on dissectable lean, fat and bone of the foreshank as predictors of beef carcass composition
Authors: Epley R. J. , Zobrisky S. E. , Chrystall B. B. , Hutcheson D. P. , Hedrick H. B. , Stringer W. C. 
Published: September 2010

SUMMARYRegression equations predicting weight and percentage of both forequarter and total side retail cuts from 126 beef carcasses were calculated. Dissectable shank muscle weight, shank bone weight and shank soft tissue weight, but not shank fat weight, were useful in predicting weight of forequarter and total retail cuts. However, intact shank weight was as valuable as any single dissection component of the shank in predicting weight of both forequarter and total retail cuts. Separable muscle, fat, bone and soft tissue percentages of the shank were not useful in predicting percentage retail cuts of either the forequarter or the entire right side.
Effects of crossbreeding and certain environmental factors on multiple births, wool production and growth in sheep
Authors: Fahmy M. H. , Bernard C. S. 
Published: September 2010

SUMMARYMultiple birth percentage and wool production were studied on 338 ewes (907 lambing and 873 shearing records) representing two purebreds, Oxford (O) and Suffolk (S), and four crossbreds, O × S, S × O, Cheviot (C) × O and C × S mated to purebred and crossbred rams during 9 years. Oxford ewes had 24–32% (P<0·01) fewer multiple births than ewes of the other groups, while little difference between S and the crossbreds was observed. The heterosis of the OS and SO groups was 14·6 ± 4·1%. Multiple births tended to increase 0·8% for each kg increase in body weight of the dam (r = 0·13). The repeatability estimate for multiple births was 0·24. Fleece weight was significantly affected by age and by breed group, with OS and SO crosses producing 17% more wool than their parental breeds. The repeatability of fleece weight was estimated at 0·52 ± 0·15. Fleece weight was significantly correlated with multiple birth percentage (0·09) and body weight (0·32).Suffolk ewes averaged 9·5 kg heavier than O ewes throughout their reproductive life. The two reciprocal crosses were heavier than both parental breeds. Suffolk ewes reached their maximum body weight at 4 years of age while Oxfords continued to gain weight up to 6 years.
Ammonium salts of fatty acids for milk production. 3. The effect of a salt solution containing ammonium acetate on milk yield and composition in Jersey cows fed on a high concentrate diet
Authors: Khalifa H. A. , Prescott J. H. D. , Armstrong D. G. 
Published: September 2010

SUMMARY1. The experiment involved four pairs of Jersey cows in a double reversal trial with two treatments.2. The control and acetate treatments involved iso-caloric concentrate mixtures together with hay. The concentrates and hay were given in constant ratio of 3 : 1 and total feed intake was regulated according to milk yield. Cows on the acetate treatment received a dilute solution of fatty acids (1·7 % w/w) and an all-cereal concentrate mixture; those on the control diet received water and a concentrate containing 10% groundnut meal. The dilute solution of fatty acids provided approximately 31 % of the total digestible crude protein intake as ammonia-N, and 208 g acetate and 34 g propionate per day.3. The two treatments gave similar dry-matter intakes. The acetate treatment caused a slight and significant depression of milk yield but the fat content of the milk and fat-corrected milk yield were slightly increased by treatment, though not significantly so. The results have been discussed with reference to the end products of digestion in the rumen and role of ammonia-N as a substitute for protein-N.
The roughage requirement of the early-weaned calf
Authors: Kang Hi Shin , Leibholz Jane 
Published: September 2010

SUMMARYAn experiment was conducted with 50 male Friesian calves between 5 and 11 weeks of age. Milled wheat straw (0·95 cm screen) was included in a pelleted all-concentrate diet at concentrations of 0, 15, 30 or 45 %. The nitrogen content of the diets was maintained by the addition of urea. The diets were given alone or with a chaffed lucerne hay or wheat straw supplement ad libitum. All diets contained 2 % sodium bicarbonate.The feed intake and weight gains of the calves were increased significantly by the inclusion of 15 % milled wheat straw, but were reduced by 30 or 45 % straw. The supplements of chaffed wheat straw or lucerne hay ad libitum did not influence the performance of the calves. The inclusion of wheat straw in the diets reduced their dry-matter digestibility but the digestibility of acid detergent fibre was maximal with 27 % straw. The digestibility of nitrogen was significantly increased by 15% straw but reduced by further increases in straw.The inclusion of wheat straw in the diets did not influence the pH of the rumen contents or the concentration of total volatile fatty acids in the rumen. Increasing the level of straw in the diet caused a significant linear increase in the proportion of acetic acid and decreases in butyric, propionic and valeric acids.
A note on the comparison of digestion by New World camels, sheep and ponies
Authors: Hintz H. F. , Schryver H. F. , Halbert M. 
Published: September 2010

SUMMARYDigestion trials were conducted with four ponies, two sheep and two New World camels (one llama and one guanaco) given alfalfa pellets and a complete pelleted hay-grain diet. The New World camels were significantly more efficient in the digestion of dry matter, neutral-detergent fibre, acid-detergent fibre and cellulose than the sheep or ponies.
A note on the effect of sudden changes in the composition of the diet of growing pigs
Authors: Livingstone R. M. 
Published: September 2010

SUMMARYTwo diets, one based on barley and white-fish meal and the other on oats, wheat and meat and bone meal, with similar concentrations of digestible energy, crude protein, lysine and methionine+cystine were used to investigate the effects of sudden changes in the composition of the diet on the performance of pigs growing from 32 kg live weight, over a period of 77 days.The diets were given separately, alternated weekly with sudden changes from one diet to the other, or as a 1:1 mixture.Changes in diet per se had insignificant effects on performance.
Moist barley preserved with propionic acid in the diet of the growing pig
Authors: English P. R. , Topps J. H. , Dempster D. G. 
Published: September 2010

SUMMARYThe feeding value of three forms of acid-treated moist barley, viz. 26 % moisture and either rolled or plate-milled, and 29 % moisture plate-milled, was compared with that of dried hammer-milled barley for growing pigs from 23 to 87 kg live weight. Two feeding experiments were undertaken, one in which individual pigs were given the same amount of dry matter from all the diets, while in the other, groups of pigs were fed ad libitum. Digestibility of the diet was determined in a third experiment.In both feeding experiments differences between treatments in efficiency of utilization of dry matter in the feed were significant (P<0·05), that for the diet containing dried barley being approximately 5% better than the other three. There were no significant differences between treatments in intake of dry matter, rate of growth and carcass quality of the pigs. However, pigs fed on dried barley apparently grew more rapidly than those given any of the acid-treated moist barleys. Differences in digestibility of the diets were very small and not significant except for crude protein. Differences in digestibility of protein (P<0·05), however, were not consistent with differences in efficiency of conversion of dry matter in the feed.
The possible use of superovulation and embryo transfer in cattle to increase response to selection
Authors: Land R. B. , Hill W. G. 
Published: September 2010

SUMMARYThe possible use of superovulation and embryo transfer in selection programmes in cattle is investigated theoretically, in terms of both rates of response and inbreeding.In a selection programme for growth rate, it should be possible to achieve about twice the response of a conventional performance testing programme, so that 400-day weight, for example, could be increased by 16 rather than 9 kg per year.The improvement of reproductive performance by the use of laparoscopy to measure the natural ovulation rate of animals over several oestrous cycles followed by superovulation of selected animals is investigated. The rate of progress is dependent upon the incidence of twin ovulations in the base population and is unlikely to exceed 0·6% per year unless the initial frequency is 8% or more.
Analyses of some factors which affect the productivity of beef cows and of their calves in a marginal rainfall area of Rhodesia. 1. Factors affecting calving rate
Authors: Richardson F. D. , Oliver J. , Clarke G. P. Y. 
Published: September 2010

SUMMARYThe productivity of cows grazing on veld was studied over four breeding seasons. Different amounts of concentrates were given to three groups of cows during winter and up to 8 weeks post partum. Half of the cows in each group had their calves weaned early (150 days) and the others at the normal time (240 days). Cows given concentrates produced more calves than those given none but time of weaning had no consistent effect on successful conception rates (as judged by subsequent calving rate).Probit analyses were used to determine the relationship between seasonal body-weight change in the cow and the probability of successful conception. The estimated percentage body-weight changes from autumn peak to mean body weight at the beginning and end of the mating season, which would be followed by successful conception rates of 50%, 75% and 90%, were −14%, −6% and +1% of autumn body weight, respectively.The practical implications of these results are discussed.
A note on digestibility in sheep as influenced by level of intake
Authors: Robertson J. B. , Van Soest P. J. 
Published: September 2010

SUMMARYDigestibility of dry matter, energy and cell wall was measured in two series of digestibility trials in which sheep were fed on pelleted mixed rations containing either 32·0 or 22·6% cell wall at various levels of intake. There were significant depressions in digestibility of all nutritive components as the level of intake increased. The ration lower in cell wall showed smaller declines in dry matter and energy digestibility but a greater decline in cell wall digestibility. The results indicate that the cell wall fraction of concentrate-supplemented rations for sheep is a primary factor in the decline in digestibility observed with increase in level of intake.
Relations between first and second lactation characters of progeny groups and effects of tandem selection on yield improvement
Authors: Bar-Anan Reuven 
Published: September 2010

SUMMARYCorrelations and regressions between estimated breeding values for 122 day part-lactation, 1st and 2nd lactation yield (part, 1st, 2nd) were estimated from 106 sire progeny groups, each with at least 60 effective daughters.The genetic correlations between part, 1st and 2nd kg milk were 1·0 and 0·84 respectively, and the regressions of 1st on part and of 2nd on 1st test were 2·40 and 0·82 kg/kg milk, respectively. Selection by one standard deviation between sires on part-lactation tests would improve 1st lactation yields by an average of 204 kg milk with a standard deviation of 84 kg. Selection on 1st lactation yields by one standard deviation would increase 2nd lactation yields by an average of 183 kg milk with a standard deviation of 156 kg, indicating that some bulls so selected could have below average 2nd lactation yields.Two sire selection models were simulated differing in the selection criterion; 1 st yield in model 1, and 1 st followed by 2nd yields in model 2. The contribution of proven sires to the rate of genetic improvement in lifetime production was greater from model 2 than from model 1 by about 15% without any additional costs for bull maintenance.
The growth of Ayrshire cattle: an analysis of linear body measurements
Authors: Russell W. S. 
Published: September 2010

SUMMARYThe growth of 12 linear body measurements in Ayrshire cattle was analysed by least-squares methods. Measurements were taken at 3-monthly intervals up to 48 mo of age. Adjustments were made for month and year of birth and for type of birth (twin-born animals comprised 40% of the data). The state of pregnancy or lactation in heifers was also taken in account. Growth curves were fitted to the mean values at the 16 ages and were found to give a close fit. Residual deviations, though small, did show a systematic pattern. The estimated degree of maturity at birth ranged from about 25% for measures of width to 50% for measures of height, body length being intermediate at 40%.To a large extent the different body measurements maintained a uniform pattern of maturing and their ranking for earliness of maturity tended to remain constant throughout the growth period. The application of allometry to the measurements is examined and the error introduced by extrapolating an allometric relationship between characters of different maturing rates is illustrated.
Polledness and intersexuality in the Damascus breed of goat
Authors: Hancock John , Louca Avraam 
Published: September 2010

SUMMARYData on 2208 parturitions involving 3594 kids were used to study the inheritance of polledness and its relationship with intersexuality in the Damascus breed of goat.The percentage of horned kids in the offspring of polled × polled and horned × horned matings was 26·8 and 100·0, respectively. The corresponding value for matings having one parent horned was 50·3%.There was a consistent excess of males in the sex ratios. Males comprised 53·8, 52·4, 60·2 and 54·0% of the offspring of polled x polled, polled x horned, horned x polled and horned × horned matings respectively. The corresponding proportions for the intersexes were 6·2, 0·3, 0·0 and 0·0%. The incidence of intersexes was not affected by type of birth (single, twin or multiple) or sex of littermates.It was concluded that the data from the Damascus breed of goat conform with the current theory on the behaviour of the P gene concerning polledness (direct dominant effect) and intersexuality (pleiotropic recessive effect) in the Swiss breeds of goat.
Mating of sows during lactation: Observations from a commercial unit
Authors: Rowlinson P. , Boughton H. G. , Bryant M. J. 
Published: September 2010

SUMMARYObservations were made on a commercial herd of female pigs (sows) where a managemental system was employed which enabled sows to be served during lactation. The system involved grouping between 2 and 8 sows together with their litters about 3 weeks post partum. The sows were fed ad libitum from grouping, and the piglets had ready access to creep food. After one day a male pig was introduced to the group. No exogenous hormone therapy was used.Results from 39 batches, comprising 180 sows, suggested that sows kept under these conditions will exhibit oestrus, and conceive during lactation with a high degree of predictability. Lactational oestrus was shown by all sows and conception to first service was 84·9%. The number of days between grouping and oestrus, and parturition and oestrus, were 11·15 ±0·28 and 35·53 ±0·47 respectively. Litter size and performance did not appear to be adversely affected by the concurrent lactation and pregnancy, either at the present or subsequent parturition. The average farrowing interval of 153 days allowed a performance of 2·35 litters/sow per year, and, with 9·47 piglets weaned/litter, a productivity of 22 piglets/sow per year.
A note on rationing of growing pigs according to age
Authors: Braude R. , Mitchell K. G. , Pittman R. J. 
Published: September 2010

SUMMARYIn a trial involving 231 pigs grown from 20 to 90 kg live weight, three methods of adjusting the feed allowance were compared, namely according to live weight and a scale with weekly adjustments, or according to age with fixed increments of feed, adjusted either weekly or every 3 weeks. Irrespective of the frequency of feed adjustment, rationing by age gave as satisfactory results in performance and carcass quality as rationing by live weight, and reduced labour requirements by eliminating the need for regular weighing of the pigs throughout the growing period.
A note on the retention of energy and nitrogen in rabbits
Authors: Blas J. C. De , Galvez J. F. 
Published: September 2010

SUMMARYOne hundred and twenty-four young rabbits of the Giant of Spain breed (mature weight, 4 to 4·5 kg) were slaughtered in groups at birth, 10, 20, 30, 40, 50 and 60 days of age.Energy retention over the six 10-day periods was 10·7, 26·5, 39·0, 48·9, 72·6 and 57·3 kcal/day, energy content per unit of weight increase was 5·18, 5·52, 5·52, 5·47, 5·80 and 5·89 kcal/g, and deposition of protein (N×6×25) was 1×45, 3×09, 4×28, 5×56, 7×31 and 5×44 g/day. The regression of the energy content of the empty body (kcal) on empty-body weight (g) was:Y = 1×734 X – 88·536with a coefficient of regression of 0·97.
Development of a synthetic pig sire line by election with immigration 2. Immigration
Authors: Webb A. J. 
Published: September 2010

SUMMARYA synthetic sire line has been developed over 11 generations by a process of selection accompanied by immigration. In each generation prospective immigrants of any breed were mated to native pigs already i n the Sire Line, and, ignoring breed, their progeny were given the same opportunity of being selected as the progeny from matings involving natives alone. This method of immigration is shown to be biased as a result of (a) heterosis in crosses of immigrants with natives, and (b) treating natives and immigrants as if they were members of the same population. When affected by both sources of bias, the breeding values of inferior immigrant progeny may be seriously overestimated with the result that inferior genes may enter the native population and hold back genetic progress. Methods of removing the bias and alternative systems of immigration are discussed.
Design and analysis of mixed grazing experiments
Authors: Connolly J. , Nolan T. 
Published: September 2010

SUMMARYNew methods of design and analysis for mixed grazing experiments are proposed and compared with previously reported designs. In general, with previous designs the effects of mixed grazing per se were confounded with other factors. The concepts of equality of grazing pressure and of livestock equivalents are examined and criticized when used as starting points for mixed grazing experiments. Two year's results of a mixed grazing experiment with cattle and sheep are analysed and provide evidence that mixed grazing is beneficial to both species in terms of production per animal. A simple economic analysis shows how the price ratio between the value per unit weight gain of the two species can be used to decide on the area of financial benefit from mixed- as opposed to single-species enterprises.