bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carcass composition in four sheep breeds: the importance of type of breed and stage of maturity
Authors: Wood J. D. , MacFie H. J. H. , Pomeroy R. W. , Twinn D. J. 
Published: September 2010

ABSTRACTIn order to investigate the effects of type of breed on carcass composition, an examination was made of 361 lambs from four breeds: Clun Forest and Colbred (termed ewe breeds); and Suffolk and Hampshire (termed ram breeds). The animals were in four carcass weight groups averaging 15, 17, 19 and 21 kg.Percentage subcutaneous fat was influenced more by carcass weight than by breed, whereas both carcass weight and breed had similar effects on percentage lean. At the mean carcass weight of 18 kg, Colbreds, the leanest breed, had a similar value for percentage lean (about 57 % of carcass tissue weight) to the carcasses over all breeds weighing 15 kg; and Cluns, the fattest breed, had a similar value (about 54%) to those weighing 21 kg. Since the ram breeds were intermediate in composition between the two ewe breeds there was no effect of type of breed on carcass composition. The breed differences were related to eventual mature size and to the stage of maturity at each carcass weight, as judged by body length and bone weight measurements. However, Colbreds were bigger and leaner than published estimates of their mature weight suggested. Humerus weight was a good predictor of lean or total fat weight, explaining 83 % ofvariation when used as a predictor along with carcass weight.Type of breed had a marked effect on internal fat deposition, the ewe breeds having heavier weights of both kidney knob and channel fat (KKCF) and caul fat (omental fat) than the ram breeds; and on the length oflimb bones, the ewe breeds having longer but thinner bones than the ram breeds. The order of the relative growth of the tissues and fat depots was: subcutaneous fat > caul fat > KKCF > intermuscular fat > lean > bone. Therefore, the internal fat depots were later maturing than intermuscular fat.The percentage of prime cuts in the carcass was not affected by carcass weight. Colbreds had significantly lower values than the other breeds. Suffolks had the lowest lean to bone ratio.
Protein requirements of male cattle fattened on diets differing in energy concentrations
Authors: Levy D. , Holzer Z. , Folman Y. , Bleiberg M. , Ilan D. 
Published: September 2010

ABSTRACTThe effects of three levels of crude protein in the diet, 10, 12 and 14 %, on the performance of entire Israeli Friesian male cattle (bulls) during fattening, was studied in two experiments.The bulls were 5 months old and 200 kg live weight, and 7·5 months and 250 kg, at the start of Experiments 1 and 2, respectively, and were slaughtered after 178 to 268 days (Experiment 1) or 156 to 166 days (Experiment 2) on trial, at a live weight of 430 to 480 kg.In Experiment 1 mixed diets of two metabolizable energy concentrations (11·1 and 10·5 MJ metabolizable energy/kg dry matter) were used, each containing concentrates with 10, 12 or 14% crude protein content. In half of the treatments the crude protein content of the concentrate was increased by two percentage units for the first 61 days of the experiment. Daily live-weight gain was significantly higher at 14% and 16% crude protein than at 10% and 12% crude protein during the first 61 days for animals on the high energy diet, but liveweight gain was not affected by crude protein content on the low energy diet over this period, or at either energy concentration from 62 days to slaughter.In Experiment 2 the diet consisted of concentrate, wheat straw and cotton hulls, giving a metabolizable energy concentration of approximately 10·55 MJ/kg dry matter. Daily live-weight gain did not differ significantly between concentrates containing 10, 12 or 14% crude protein, but carcass weight gain was higher at 12% and 14% crude protein than at 10% crude protein.It is concluded that in order to ensure the best performance of bulls of the Israeli Friesian breed, diets with a high concentration of energy should contain 14% crude protein when fed to animals with a body weight of 200 to 300 kg, and 12% crude protein for heavier animals.
The effect of correction factors on response to selection in beef cattle
Authors: Jones L. P. , Hopkins I. R. 
Published: September 2010

ABSTRACTProgeny of younger dams grow more slowly than those of older dams. When the environmental effects of dam age are not allowed for in selection for growth rate, selection differentials and genetic responses to selection are reduced.In a model herd, with cows aged 2 to 8 years, it was found that neglecting the dam age effects reduced genetic gains by about 15% when selection is for weaning weight, and by 11 to 7 % when selection is at an age of 12 to 20 months. Much of the reduction occurs because of the selection of higher proportions from genetically inferior groups.If genetic differences among dam age groups are small the reduction is only 7% at weaning and less at older ages. The effect of ignoring calf age was also estimated. It was found that if calves born within a period of 33 days were compared and calf age was neglected, the response to selection for weaning weight would be reduced by about 6%.
A note on the effect of social rank on the feeding behaviour of young cattle on self-feed maize silage
Authors: Leaver J. D. , Yarrow N. H. 
Published: September 2010

ABSTRACTIn two experiments young British Friesian cattle were allowed restricted access to maize silage on a self-feed system. Restrictions were imposed by either limiting the width of feed face per animal or by reducing the time available for feeding.The social order of each group of cattle was determined by observing dominance-submission interactions between pairs of individuals. Dominance rank and angular dominance values were calculated for individuals in each group and related to silage intake, feeding time and rate of eating. Silage intake and rate of eating increased significantly with dominance value, and feeding time decreased although not significantly.
Pig courtship behaviour: pheromonal property of androstene steroids in male submaxillary secretion
Authors: Perry G. C. , Patterson R. L. S. , MacFie H. J. H. , Stinson C. G. 
Published: September 2010

ABSTRACTThe influence of the odoriferous androstene steroids upon the response and courtship behaviour of gilts has been studied. These steroids are normally present in the submaxillary salivary glands of the boar, and have been shown previously to be an aid in the artificial insemination of gilts. Glands were excised from young boars after weaning, and at 6 months of age the ability of the boars to elicit a standing response from oestrous gilts was compared with that of littermate controls. In addition, a detailed record was made of behavioural activities performed by both gilts and boars, under a standard test procedure.Analysis of the data showed that the presence of the glands was essential for normal behavioural patterns in both the females and the males. When confronted with a treated boar, the gilts were affected in three ways: approaching oestrus, they did not respond as early as they did to the controls; the intensity of their response was reduced; and it was held for a shorter period. The demeanour of the treated males was passive and unconcerned, i n contrast to the easily-aroused aggressive nature of the controls. The characteristic viscous salivary secretion was absent, and the scrotal sac was less pronounced and supported closer to the body.These results suggest that elimination of the white, frothy saliva normally containing and dispersing the androstene steroids not only reduces the boar's ability to command and elicit a full sexual response from oestrous gilts, but it also reduces his own libido. In conjunction with previous work, these studies provide evidence for the pheromonal properties of androstenone and androstenol.
A note on milk intake of piglets measured by tritium dilution
Authors: Yang T. S. , Howard B. , Macfarlane W. V. 
Published: September 2010

ABSTRACTThe milk intake of two litters of suckling piglets was measured by the turnover of tritium-labelled body water. The estimated intakes of a litter of seven piglets agree with the current knowledge of milk yield from sows, which generally rises to a maximum at the 3rd week and then declines. With a litter of four, intake rose continuously from the 1st to the 6th week. Since piglets are often weaned at 3 weeks of age, this method has few disadvantages n i practical use. During the estimation of water turnover the total body water of individual piglets can also be obtained so that information on body composition (solids, protein, fat and ash) can be derived. The efficiency of conversion of milk by piglets can thus be calculated.
Induction of puberty in gilts 1. The effects of rearing conditions on reproductive performance and response to mature boars after early puberty
Authors: Paterson A. M. , Lindsay D. R. 
Published: September 2010

ABSTRACTAttainment of puberty and the ovulation rates for the first three oestrous cycles were studied in gilts reared to 160 days alongside contemporary castrate or entire males before introducing them to mature boars.Gilts which were introduced to the boars at 160 days of age reached puberty at younger ages and lighter weights than isolated gilts. Rearing treatment did not affect the age of puberty. Gilts which were isolated from boars after 160 days of age reached puberty earlier if they had been reared with entire rather than castrate contemporary males. The interval from introduction of the boars to first oestrus was related to age and weight at the time of introduction.Ovulation rate at the pubertal oestrus was the same in both isolated groups, and higher in both these groups than for gilts induced into early puberty by boars. Ovulation rate increased at the second and third oestrous cycle and groups differed only at the first oestrus. In a second experiment, the reproductive performance of gilts approximately 218 days of age experiencing either their first, second or third oestrus was studied. No differences were found among the groups and the conclusion is that in gilts of similar age and weight the oestrous cycle at which mating takes place does not affect reproductive performance.
A note on the housing of intact male and female pigs together in the same pen during the growing period to bacon weight
Authors: Barber R. S. , Braude R. , Mitchell K. G. , Thomas Joanne 
Published: September 2010

ABSTRACTA feeding trial was carried out, using 180 pigs, to assess the effect on performance when intact male and female pigs were housed together in the same pens from 20 to 90 kg live weight. There were no significant differences in daily feed intake, rate of growth or feed: gain ratio between pigs from mixed-sex pens and pigs from single-sex pens. Carcass measurements indicated slightly leaner carcasses for intact male pigs whether housed in separate pens or together with female pigs, while female pigs likewise had a significantly higher dressing percentage.
A note on a comparison of crossbreds from two prolific sheep breeds
Authors: Boaz T. G. , Jones R. , Smith C. 
Published: September 2010

ABSTRACTTwo groups of crossbred ewes, produced by crossing the Scottish Blackface with two prolific sheep breeds, the East Friesian and the Animal Breeding Research Organisation Dam Line, were compared in good lowland conditions over three ages (2 to 4 years) from 1976 to 1978. The East Friesian crossbred ewes were heavier, had larger, heavier litters and had heavier lambs at weaning. More of their lambs were slaughtered directly off their dams, at heavier weights and at earlier ages. The total weight of lamb sold per ewe was about 15% higher than for the Dam Line crossbred ewes.
The effect of daylength on the growth of lambs 3. Level of feeding, age of lamb and speed of gut-fill response
Authors: Forbes J. M. , Brown Wendy B. , Al-Banna A. G. M. , Jones R. 
Published: September 2010

ABSTRACTFour experiments, each with 24 growing sheep, were carried out to investigate the effects of 8- or 16-h daylengths on growth and carcass characteristics. In the first two experiments, with 6- to 9-month-old castrated males, and 3- to 5-month-old female and castrated male animals, pair feeding of a concentrate feed was adopted. Live-weight gains were significantly greater under 16-h daylength, but carcass weights were not significantly increased because most of the live-weight difference was due to gut-fill. Carcass weights and measurements suggested that long daylength stimulated the growth of non-fat tissues at the expense of fat.The third experiment compared castrated males fed either ad libitum or restricted to a daily ration proportional to each animal's own weight from 6 to 9 months of age. Food intake was higher in the ad libitum sheep but not significantly so. Weight gains were, however, significantly greater with ad libitum feeding and long daylength, compared with restricted feeding and short daylength, respectively. Gut-fill was greater in those kept in 16 h daylength and the small advantage in carcass weight was not significant. Carcass characteristics were not markedly affected by daylength, while carcass weight and fatness were higher following ad libitum feeding than restricted feeding.In the fourth experiment 12 female sheep, aged 9 months, were individually rationed according to live weight and slaughtered after 4 weeks exposure to 16- or 8-h daylengths; another 12 were slaughtered after 7 weeks of treatment. Gut-fill was significantly greater in long daylength at both slaughter times, showing that the effect of daylength on gut fill has occurred within 4 weeks of the start of treatment, while live weight has not been observed to be affected at this stage in any experiment in this series.Overall these experiments show little stimulating effect of long daylength on growth, and a large effect on gut-fill.
The composition of body-weight changes in underfed lactating beef cows
Authors: Chigaru P. R. N. , Topps J. H. 
Published: September 2010

ABSTRACTThe effects of reducing the feed intake of 12 winter-calving (Hereford male × British Friesian female) cows to the maintenance level for 6 weeks from week 10 of lactation were investigated during two consecutive lactation periods. Initially, six cows were in their first and six in their third lactation. In each year the period of ‘underfeeding’ was preceded by a period of ‘adequate feeding’ (maintenance plus milk production requirements) and succeeded by a period of ‘refeeding’ (2 × maintenance). Changes in body water, estimated by the dilution of tritiated water and deuterium oxide at the end of each feeding period, were used to calculate changes in body tissue. Milk yield during the period of ‘adequate feeding’ indicated that individual cows differed markedly in milk production potential. During ‘underfeeding’ milk yield was related to lactation potential. Cows of higher potential tended to maintain higher yields than those of lower potential but in doing so they incurred higher body-weight losses. The ‘refeeding’ period did not result in significant increases in milk yield. The weight losses during ‘underfeeding’ consisted mainly of fat but some cows apparently mobilized relatively large amounts of protein. More fat per unit body weight loss was mobilized by the heifers than by the cows, which, on the other hand appeared to mobilize relatively more protein. On ‘refeeding’, only a few cows were able to achieve complete tissue repletion.
A note on regional variations in the seasonality of milk production in dairy cattle
Authors: Wood P. D. P. 
Published: September 2010

ABSTRACTMean daily milk yield, fat concentration and protein concentration in the milk of 579 303 British Friesian, 6 608 Shorthorn, 27 374 Ayrshire, 19 529 Jersey and 19 760 Guernsey cattle were recorded monthly from August 1978 to July 1979 inclusive, and classified by breed, parity, stage of lactation, and five geographical areas according to the location of the herd. Parameters of the function Y(n) = anbecn were estimated for each breed/parity/area group for yield, fat concentration and protein concentration (b and c describe the shape of the curve, a is a scalar, n the week of lactation and e the base of natural logarithms). Systematic deviations from the function were associated with the season of production, reflecting the spring and summer flush of milk yield. Fat and protein concentrations also exhibited seasonal variations from the underlying curve. After correction for the seasonal fluctuation in production, there was no variation in total yield, fat concentration or protein concentration associated with the month of calving.
A note on a possible association between plasma β-carotene levels and conception rate in a group of winter-housed dairy cattle
Authors: Jackson P. S. 
Published: September 2010

ABSTRACTThree groups of winter-housed Friesian cows were fed according to maintenance and production requirements on dairy cake and poor quality hay for 5 weeks (5 cows), 4 weeks (4 cows) or 2 weeks (3 cows). They were then treated as one group with two injections of 500 μg cloprostenol 11 days apart to synchronize oestrus, followed by insemination 72 and 96 h after the second treatment.Blood samples were taken for β-carotene estimation 1 day before the first cloprostenol injection, 3 days before the second injection, and the day after the second insemination. Conception was confirmed by rectal examination. Haematological parameters and metabolic profiles for all 12 cows were in the normal range and condition scores showed no correlation with time of conception. However, plasma β-carotene levels declined rapidly and uniformly between the three sample points for all cows. The individual animal means were directly correlated with length of time on the described diet and with time of conception (P<005). A theory of β-carotene involvement in ovarian function is advanced.
A note on the eating quality of pork from lean pigs
Authors: Wood J. D. , Mottram D. S. , Brown A. J. 
Published: September 2010

ABSTRACTSixteen pork carcasses were purchased from those exhibited in Class 146 at the Royal Smithfield Show 1978 (i.e. pork carcasses of 48 to 61kg dead weight, age <5 months). Eight had thinner backfat than the average for the class (‘very lean’ group with 6 mm fat over m. longissimus at the last rib and estimated lean content in side of 63%), while eight had thicker backfat than the average (‘lean’ group with 12 mm fat over m. longissimus at the last rib and estimated lean content in side of 57%). Both groups were leaner than the national average. The carcasses were returned to the Meat Research Institute for eating quality assessments. Muscle quality was similar in both groups. Toughness (assessed instrumentally), tenderness and flavour (assessed by taste panellists) were also similar. Juiciness was lower in the ‘very lean’ group but was not matched by higher cooking losses and the difference was considered to be relatively unimportant. In conclusion, the eating quality of pork is maintained at very low values of carcass fatness.
Beef production from silage 1. The voluntary intake and live-weight gain of beef cattle given red clover silage
Authors: Thomas C. , Aston K. , Gibbs B. G. , Tayler J. C. 
Published: September 2010

ABSTRACT1. The primary growth of a tetraploid red clover was cut from 17 to 19 June and ensiled with formic acid at 3·81/t fresh crop (F), equal volumes of formic acid and formalin at 9 11/t (67 g formaldehyde per kg crude protein) (FF) or wilted and ensiled without additive (W). The silages were given ad libitum either alone or with supplements of dried grass or barley/fish meal at 6·7 g dry matter per kg live weight to 45 British Friesian male castrates, initially 3 months old and 104 kg live-weight.2. The use of formaldehyde reduced the concentration of fermentation acids and of ammonia-nitrogen in the silage. Wilting the crop increased silage dry-matter content by 74g/kg fresh weight but this silage had the highest concentration of fermentation acids and of ammonia-nitrogen.3. Digestibilities of diets containing silage FF were lower than those of diets containing silages F and W except when silage FF was supplemented with dried grass (interaction P <0·05).4. The intake of silage W was on average higher than that of silages F and FF (P < 0·001). Supplements of barley/fish meal and dried grass depressed silage intake to a similar extent (P <0001). When silages were given as the sole feed, calves consuming silage F had higher live-weight gains than calves given silages FF and W (P <001). This effect was not apparent when silages were supplemented with barley/fish meal, but with a supplement of dried grass the calves given silage FF grew more slowly than those given silages F and W.5. The results are discussed in relation to the possible effect of treatments on the supply of rumen-degradable protein and of amino acids to the animal.
Physiological attributes as possible selection criteria for milk production 2. Plasma insulin, tri-iodothyronine and thyroxine in bulls
Authors: Osmond T. J. , Carr W. R. , Hinks C. J. M. , Land R. B. , Hill W. G. 
Published: September 2010

ABSTRACTInsulin, thyroxine and tri-iodothyronine concentrations were measured in samples of blood from 175 Friesian bulls, aged between 2 and 7 years, which were being progeny-tested for milk production. Least squares regression coefficients were estimated for these hormone levels on time of day and time after feed at sampling and age of bull. Correlations between hormone levels and Improved Contemporary Comparisons of the bull, a measure of his daughters' milk production, did not differ significantly from zero, suggesting that simple spot estimates of levels of these hormones in bulls would not supply useful predictors of daughters' production.
Starling damage on farms using the complete diet system of feeding dairy cows
Authors: Feare C. J. , Wadsworth J. T. 
Published: September 2010

ABSTRACTMost farms that were feeding complete diets to dairy cows in the east midlands lost barley to starlings during the 1978/79 winter and more outdoor than indoor feeding sites were infested. The maximum total loss recorded on any one farm was 11 -881, this being 9% of the 1321 of barley presented to the cattle. The presentation of ground barley, rather than rolled barley, reduced the quantity of grain removed by starlings but the proofing of buildings i n which cattle are fed complete diets is suggested as the most effective means of preventing this food loss.
A note on the influence of boar age on its ability to advance puberty in the gilt
Authors: Kirkwood R. N. , Hughes P. E. 
Published: September 2010

ABSTRACTTwenty-four Large White × (Landrace × Large White) gilts were allocated to one of four treatments such that one gilt from each of the litters was on each treatment. Three of the treatments involved 30-min daily contact with a boar, the boar being either (1) 2 years of age, (2) 11 months of age, or (3) 6·5 months of age, at the start of the trial. The fourth group were controls, receiving no boar stimulation.The experiment began at a gilt age of 165 days and continued until puberty was detected. The gilts were slaughtered 5 days after puberty was reached.The results indicate no significant difference for age at puberty between gilts exposed to the 2-year- or 11-month-old boars (182·0 v. 181·6 days respectively), although both were significantly younger at puberty than gilts exposed to the 6·5-month-old boars or having no boar contact (P<001) (206·0 v. 203·0 days respectively).