bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Fleece of Wiltshire × Wensleydale Sheep
Authors: Ryder M. L. 
Published: September 2010

AbstractThe coat of 16 Wiltshire × Wensleydale lambs was investigated and all were woolly, with no halo hairs on the back. The bulk of the coat consisted of curly-tip fibres, and most lambs had Valley (8) or Plain (6) fibre-type arrays, only two having Ravine arrays.There was little difference in diameter between the primary and secondary fibres in the skin, and some evidence of ‘checking’ in the central primaries. The secondary/primary follicle ratio of 4·26 compared with a mid-parent value of 4·5. There was less latticed medullation in the crossbreds than in the Wiltshire.The adult fleeces were visually similar to those of the Wensleydale and were intermediate in weight and staple length between the parent breeds. These findings could have practical application in the improvement of ‘hair’ sheep, in that a first cross with the Wensleydale would have a fleece of medium wool lacking hair or kemp.
The profile area of beef carcasses and its relationship to carcass composition
Authors: Fisher A. V. 
Published: September 2010

SUMMARYThe relationship was examined between the composition of carcasses from 30 castrated Hereford male cattle and their profile areas obtained from photographic negatives. The accuracy of this method n i determining fatness was compared with that of other methods including visual assessment.Photographs were taken of a dorsal view of the intact carcass and lateral and medial views of the left side after splitting the carcass. A planimeter was used to measure the areas which were obtained from photographic negatives. Carcass lengths were recorded from the medial views. A panel of six judges assessed the sides for fatness on a seven-point scale with the aid of photographic standards.Areas and carcass lengths, adjusted to dimensional parity, were used as independent variables in multiple regression analyses, with the weights of the dissected tissues as dependent variables. Explanation of variation in muscle weight was poor, but dorsal area and length were (very nearly) as good as visual score and side weight in predicting total fat weight.
Evolution of various adipose deposits in growing rabbits and sheep
Authors: Vezinhet A. , Prud'hon M. 
Published: September 2010

SUMMARYThe importance of the different adipose deposits with respect to the total dissectible fatty tissue in growing rabbits and lambs was studied. Development of the subcutaneous fat in the lamb is late and occurs after birth. In contrast, the internal types of fat, such as the perirenal and pelvic fat, represent at birth an important percentage of the total fat. They tend to lose part of their relative importance between 0 and 250 days after birth. In the rabbit the situation concerning the development of subcutaneous and perirenal fat is inverted. For both species the intermuscular fat remains almost constant in relative importance during the whole growth period.After the period required for the establishment of the different fat deposits, we could observe in lambs, and to a smaller degree in rabbits, a relative growth which tends to become isometric with regard to the total fat deposits.
Differences in feed intake and the performance of Finn × Dorset ewes during late pregnancy
Authors: Shevah Y. , Black W. J. M. , Land R. B. 
Published: September 2010

SUMMARYIn two experiments carried out in the autumn of 1971 and 1972 (treatment prefixes 1 and 2 respectively), 84 Finn x Dorset ewes found by X-ray to carry from 1 to 4 foetuses were individually fed during the last 6 weeks of gestation either: 1A,ad libitum; 1H and 2H, 33 kcal M/kg ewe live weight+365 kcal per ME/kg foetus (anticipated birth weight); 1M, 80%; and 2L, 50% of the total energy fed to treatments 1H and 2H. The amounts given remained constant during the experimental period. The method of feeding according to foetal number within treatments, attempted to standardize the nutritional state within treatments.All ewes (except those on 2L which remained constant) gained 6 to 8 kg live weight during the last 6 weeks of gestation and lost 8 to 10 kg at parturition. The birth weight of lambs was not affected by the range of energy (2·3 to 4·4 Meal ME/ewe per day) consumed during the last 6 weeks of gestation.Plasma concentrations of free fatty acids (FFA), glucose and ketone bodies were determined weekly. The mean FFA levels were significantly higher in the low energy treatment groups than the high ones.The present data indicated that if there is little change in body weight i n the early stages of pregnancy a 65 kg ewe bearing twin lambs, will require about 4 Meal ME/day during the last 50 days of gestation t o prevent a rise in plasma FFA concentration or loss of weight over the gestation period.
A note on the effect of twin births on production in the subsequent lactation
Authors: Wood P. D. P. 
Published: September 2010

SUMMARYA study of the British Friesian Cattle Society's herdbook for 1961 showed that twin births were registered from 323 cows which had borne single calves the year before, and which had 2009 contemporaries of the same age calving single births in the same two seasons and in the same herds.Least squares means of milk yield and fat percentage calculated from the truncated 305-day lactation showed that the twin mothers exceeded their contemporaries by 118±47 kg milk in lactations 2 days shorter. After correction for herd and year effects there was no difference between the twin birth lactation yield and the preceding single birth yield.There was a reduction in fat percentage of 0±06% associated with the twin birth lactation.The proportion of a sample of 194 twin mothers failing to calve again was 24±3% against 19±1% of the mothers of single calves, but no reasons for culling had been recorded.
A note on the prediction of silage intake by cattle
Authors: Richards I. R. , Wolton K. M. 
Published: September 2010

SUMMARYIn a series of feeding trials, measurements were made of silage drymatter (DM) content and pH, animal live weight and intake of DM other than silage. Silage intake has been related to these measurements by multiple regression. Subsequently, within the recorded ranges of the variables used, good predictions have been made of silage intake by large groups of cattle.
Observations on the effect of levamisole treatment on the production of dairy cows in England
Authors: Fox M. T. , Jacobs D. E. 
Published: September 2010

ABSTRACTA field study involving 1087 cows and 191 heifers on nine carefully selected English dairy farms was conducted to evaluate the effect of nematocidal treatment on subsequent milk production. As many of the cattle as possible were allocated to pairs according to specific criteria and dosed with either levamisole and oxyclozanide, or oxyclozanide alone, soon after calving. The remaining unpaired animals were assigned alternately to the two treatment groups according to calving date. The milk production and health status of all the cattle in the study were closely monitored.Analysis of pooled milk production data over a 2-year period failed to show a statistically significant response to nematocidal treatment. When individual herd data were analysed, a significant response to treatment was recorded on one farm. It was noted that the apparent value of the response varied according to method of analysis.Factors considered likely to account for differences in response between farms and also between trials are considered.
Estimates of genetic parameters for milk and fat yield for the first three lactations in British Friesian cows
Authors: Meyer Karin 
Published: September 2010

ABSTRACTA multivariate restricted maximum-likelihood procedure was used to estimate variance and covariance components between and within sires. This method, which considered all lactations simultaneously, accounted for the bias in later lactation records due to selection on dairy performance. Analysis was carried out for a mixed model with herd-year-seasons as fixed and sires as random effects, and fitting lactation length, calving age and month within season of calving as covariables. The data included 26 176 first, 19 978 second and 14 868 third lactation records for 679 test sires, and were analysed in 13 subsets. Additional records for proven sires, treated as fixed effects, were included to improve the data structure.Estimates for all components were higher in later than in earlier data sets, probably, to a large extent, because of a scale effect. Pooled estimates of heritabilities for lactations 1 to 3 were 0·28, 0·19 and 0·24 for milk yield, and 0·27, 0·21 and 0·25 for fat yield. Genetic correlations of 0·91, 0·91 and 0·95 for milk yield, and 0·91, 0·91 and 0·99 for fat yield, were found between lactations 1 and 2, 1 and 3, and 2 and 3, respectively. Results suggest that dairy performance in all lactations is almost identical genetically.
Plasma metabolite and hormone concentrations in Friesian cows of differing genetic merit measured at two feeding levels
Authors: Flux D. S. , Mackenzie D. D. S. , Wilson G. F. 
Published: September 2010

ABSTRACTPhysiological differences between cows in hormone and metabolite concentrations were sought that may account for genetic differences in milk production.Two groups of New Zealand Friesian cows, differing in genetic merit for fat production (high breeding index (HBI) and low breeding index (LBI)) by approximately 23 breeding index units (20 kg fat on the United Kingdom improved contemporary comparison scale), were each divided into two further groups, one of which was given freshly cut pasture to appetite and in the other intake was restricted to 70% of appetite. Eighteen blood samples were collected over a 24-h period from each of 16 cows fitted with indwelling jugular catheters. Samples were analysed for growth hormone, insulin, free fatty acids and β-hydroxybutyrate. Mean concentration of insulin was significantly higher in the HBI underfed group than in any other group (P< 0·01). Glucose concentration was significantly lower in the LBI group (P< 0·05), whose intake was restricted. The concentration of (3-hydroxybutyrate was significantly higher in the cows whose intake was restricted (P< 0·01) and the concentration fell markedly after feeding. Growth hormone concentrations were higher in the cows on restricted intake (P< 0·05) and in HBI cows but the differences were not statistically significant.It was concluded that different patterns of blood metabolites and hormones are associated with cows that differ in genetic merit. Aspects of insulin and glucose metabolism, particularly at low planes of feeding, appear to offer most promise as indicators of high milk-solids production.
The estimation of killing out in cattle from knowledge of breed, and visual appraisal of external fat cover and conformation
Authors: Bailey P. J. , Cook G. L. , Kempster A. J. , Sains A. G. 
Published: September 2010

ABSTRACTData for a total of 3715 cattle from four sources were used to examine the relative importance of live weight at slaughter, and visual assessments of carcass conformation and subcutaneous fat cover, as predictors of killing out. The sources were the Meat and Livestock Commission's beef breed evaluation programme (1689 steers of different breeds and crosses), the beef demonstration unit at the National Agricultural Centre, Stoneleigh (814 commercial dairy-bred cattle), an East Anglian abattoir (405 commercial cattle) and the Milk Marketing Board's Warren Farm (807 dairy-bred steers by different sire breeds). An assessment of live body conformation was also examined as a predictor in the Warren Farm data.Carcass conformation provided a more precise prediction of killing out than did either live weight or subcutaneous fat score. Regression coefficients in the different groups ranged from 5·4 to 12·0 g/kg for each increase in conformation class (six-point scale). The live conformation assessment was a less precise predictor (within sire breed residual s.d. = 17·7 g/kg) than the carcass assessment (15·6 g/kg).
Methods of analysing the effect of season of birth on weaning weight in a zebu × temperate beef herd in Kenya
Authors: Carles A. B. , Riley Janet 
Published: September 2010

ABSTRACTA study was made of weaning weights in a beef herd, using a rotational crossbreeding system including the Boran breed (zebu) and two temperate beef breeds (Devon and Limousin), and a seasonal calving period spanning the onset of the rains.Significant sources of variation in calf weaning weights were crossbred type, age at weaning, sex, dam's age, season of birth, year and a year × crossbred type interaction (all P < 0·001).The adjusted mean weaning weight was 203 kg. Weaners sired by a temperate bull were generally 1·08 times the weight of those sired by a zebu bull. Steers were 1·06 times the weight of heifers. Marked increases in weaning weights occurred as dams increased in age from 3 to 6 years and slight increases continued up to 9 years of age. Weaners born to 9-year-old cows were 1·09 times the weight of those from first calvers.Alternative methods for investigating the effect of season of birth were examined and the final choice was a covariate for time from birth to the onset of the rains. Calves born in the earliest part of the calving period were approximately 1·14 times the weight of those born just after the onset of the rains.
The heritabilities and genetic correlations among eight blood constituents, and their relationship to aspects of performance and genetic polymorphisms, in the sheep
Authors: Woolliams J. A. , Wiener G. , Field A. C. 
Published: September 2010

ABSTRACTBlood samples were taken from Scottish Blackface ewes of five lines (selected for long and short cannon bones, for hairy and fine fleeces, and an unselected control line) at ages ranging from 9 to 69 months. The samples were analysed for the concentrations of copper, glucose, calcium, magnesium, phosphorus, total protein, albumin and globulin in plasma.The components of variance and covariance between sires and within sires were estimated and heritabilities were calculated for the eight blood constituents and live weight. The heritabilities ranged from 0·20 (s.e. 0·08) for the concentration of copper to 0·43 (s.e. 0·10) for total protein. Only one of the 34 genetic correlations was significantly different from zero, this being between the concentrations of calcium and phosphorus.Ewes that had had a single lamb 9 months earlier had lower concentrations of copper, calcium, albumin (P < 0·001) and glucose (P < 0·01) than ewes that had not lambed. Concentrations of glucose (P < 0·05) and total protein (P < 0·001) were also decreased according to the number of lambs born to the ewe 3 months later.Ewes with low red cell potassium concentrations had higher concentration of glucose in plasma than ewes with high red cell potassium concentrations (P < 0·05). Haemoglobin type affected the concentrations of copper (P < 0·01) and total protein (P < 0·05), with ewes of type B having higher and lower concentrations respectively. The constituents measured were not significantly affected by transferrin type.
The effect of daylength on the growth of lambs. 5. Skeletal long photoperiod
Authors: Brinklow B. R. , Jones R. , Forbes J. M. 
Published: September 2010

ABSTRACTFour experiments were carried out, with a total of 98 Suffolk-cross lambs fed at a restricted level, to study the effects of skeletal long photoperiod (7 h light: 10 h dark: 1 h light: 6 h dark) compared with short photoperiod (8 h light: 16 h dark) on growth and blood levels of hormones. The experiments started when the lambs were from 2 to 10 months of age and continued for 9 to 14 weeks.In the first experiment, the weight gains of both females and castrated males were significantly increased by skeletal long photoperiod. Plasma prolactin was increased and cortisol decreased by skeletal long photoperiod.Experiment 2 included females and castrated males; prolactin was stimulated by skeletal long photoperiod and there was a significant positive correlation between live-weight gain and prolactin.The weight gains and carcass characteristics of the female lambs used in the third experiment were not affected by photoperiod. Live-weight gain was negatively related to plasma cortisol.In experiment 4, there were 12 intact males and 12 castrated males. The intact animals grew significantly faster; skeletal long photoperiod caused a depression in testosterone levels in plasma even though it tended to increase live-weight gain.When the data from all four experiments were pooled, it was found that skeletal long photoperiod gave a significant increase in live-weight gain in animals whose pineal gland was intact (40 per photoperiod; 138 v. 113 g/day); there was no effect on gut fill at slaughter and the increase in carcass weight (0·5 kg) was not significant.
The effect of age on halothane susceptibility in pigs
Authors: Carden A. E. , Webb A. J. 
Published: September 2010

ABSTRACTThe effect of age on incidence of susceptibility to halothane anaesthesia in pigs was studied on animals that were repeatedly exposed to the anaesthetic. In three trials, 232 Piétrain/Hampshire and 201 Landrace pigs were given three 3-min halothane tests, at 19, 35 and 54 days of age. In a fourth trial 253 Landrace pigs received four 5-min tests, at 21, 35, 49 and 63 days. All pigs were offspring of positive × positive matings. Maximum-likelihood estimates of the probability of positive reactions were 0·47, 0·73 and 0·88 at the three ages in Pietrain/Hampshire; 0·20, 0·63 and 0·60 in the first Landrance trial; and 0·64, 0·86, 0·84 and 0·90 in the second Landrace trial. Thus, in all trials, the incidence of halothane positive reactions increased with age. In both breeds and at all ages, the incidence was lower in males than in females.
A note on energy requirements for maintenance of lean and fat Angus, Hereford and Simmental cows
Authors: Ferrell C. L. , Jenkins T. G. 
Published: September 2010

ABSTRACTMature Angus (A), Hereford (H) and Simmental (S) cows (16 each) that had been randomly assigned and fed a maize silage-based diet at different levels of intake during lactation were selected.Lean and fat A, H and S cows were fed the maize silage-based diet individually to provide metabolizable energy (ME) intakes of 542, 506; 476, 437; and 624, 597 kj/kg0.75 per day respectively for 84 days. Daily weight gains of lean cows were greater than those of fat cows (0·40 v. 0·11 kg/day) even though daily ME intakes were less (55·2 v. 62·4 MJ/day). Theoretical estimates of ME requirements for maintenance were less for lean than for fat cows, and maintenance of A and H cows tended to be less than those of S cows.These results suggest that cow maintenance requirements increased in association with fatness that resulted from the previously imposed nutritional regimes and tended to differ among cow breeds.
Heat loss from groups of growing pigs under various conditions of environmental temperature and air movement
Authors: Holmes C. W. , Mount L. E. 
Published: September 2010

Continuous measurements of heat loss throughout the 24 hours have been made on groups of pigs living in a large direct calorimeter equipped as a pig pen. Five experiments, each lasting 24 days, were carried out on groups of six pigs each weighing about 20 kg, and these were repeated when body weight was 60 kg on groups of three pigs, chosen from the original six in each case. Each group was exposed initially to an environmental temperature of 20°C for 10 days, followed by either 9°C (two groups at each weight), 30°C (two groups at each weight), or a continuation of 20°C (one group at each weight). In another experiment lasting 66 days a group of four pigs was exposed to 12 and 20°C at two levels of air movement.Heat loss from the groups showed a marked 24-hr cycle, with a maximum n i the afternoon and a minimum in the early morning. The mean amplitude of the cycle at 20°C was 20% of the mean value; this proportion increased at 9 and 12°C.Heat loss was approximately proportional to (body weight)1·0 over the weight range 17·34 kg, and to (body weight)0·8 over the weight range 35·54 kg, when food intake increased in proportion to (body weight)1·0. Over the weight range 55·67 kg, when food intake was constant at 1·83 kg/day per pig, heat loss was proportional to (body weight)0·4. In both 20 and 60-kg pigs, heat losses showed little difference between 20 and 30°C, but were increased at 9°C.Evaporative loss from the pen, as a proportion of total heat loss, was approximately 21% at 9°C, 29% at 20°C, and 61% at 30°C. Voluntary water intake exhibited a marked 24-hr cycle similar in timing to the heat loss cycle.There was no lasting effect on heat loss associated with raising the mean air movement rate in the pen from 10 to 26 cm/sec.
The effect of source and level of dietary protein on the performance of in-lamb ewes
Authors: Forbes T. J. , Robinson J. J. 
Published: September 2010

The aim of the investigation was to evaluate the specific effect, if any, of grass protein on the birth weight of lambs born to ewes wintered indoors. Grass meal was used as a substitute for fresh grass, and soya bean meal—representing a more conventional source of protein for winter diets—was compared with it. Both sources of protein were included at two levels, providing a high (90 g or 0·2 lb/day) and a low (45 g or 0·1 lb/day) intake of digestible crude protein.The digestibility of dry matter was significantly higher for the diets containing soya bean meal (67·7%) than for those containing grass meal (58·2%). Dry-matter digestibility was not affected by level of protein intake. The digestibility of crude protein was significantly affected by protein source and level of intake.Lamb birth weights were not significantly affected by source or level of dietary protein. There was a tendency for birth weights to be higher on the diet containing grass meal at low protein intakes. Ewe weight gains during the last eight weeks of gestation were significantly affected by level of dietary protein, and net body weight change was significantly affected by both source and level of protein. Gestation treatments had no effect on the performance of ewes or lambs during the first three weeks of lactation.The retention of nitrogen during the 18th–20th weeks of gestation was affected by both source and level of dietary protein. Mean nitrogen retention was higher with diets containing soya bean meal (5·8 g per day) than with diets containing grass meal (3·6 g per day). There was no correlation between nitrogen retention and lamb birth weight.
The influence of castration on the growth of male pigs in relation to high levels of dietary protein
Authors: Prescott J. H. D. , Lamming G. E. 
Published: September 2010

1. A factorial split-plot experiment was conducted to investigate the growth of entire and castrate male pigs on conventional diets and diets containing higher levels of protein. Thirty-two Large White pigs were fed ad libitum from 50 lb to slaughter at 260 lb live weight. The carcasses were dissected.2. The live-weight gain of entire males was the same as that of castrates on the conventional diet, but they grew non-significantly faster than castrates on the higher protein diet.3. The entire males had a lower dressing percentage and less fat in the carcass than the castrates, but more lean, bone and rind, and a similar lean: bone ratio. The leanness of the entire males was increased on the higher level of dietary protein whereas the leanness of the castrates was unaffected except in the leg. The interactions were not significant.4. The carcasses of the entire males were proportionately heavier in the head and shoulders and lighter in the middle than those of the castrates.5. The majority of the entire males had flesh with a slightly tainted flavour.