bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gestation period, litter size and birth weight in the goat
Authors: Amoah E. A. , Bryant M. J. 
Published: September 2010

ABSTRACTData from 265 female goats (does) from seven herds in Year 1 and 130 does from four herds in Year 2 were analysed using a general linear interactive model for factors affecting gestation period (GP), litter size (LS) and birth weight (BW) of offspring (kids). Gestation period could be described by the regression equation GP = α – 0·890LS –1·072S where S is the proportion of male kids in the litter and the constant (a) depends on breed and herd and was 154·240 (s.e., 0·843) days for British Saanen does in Herd 1. The model established for LS was a quadratic regressional relationship LS = a – 0·000103 (MW - 60))2 + 0-0172 (MW -60) where MW was live weight of the doe at mating and a at MW = 60 kg depends on herd and period of kidding. For early-kidding does in Herd 1 a was 2·277 (s.e., 0·090) kids. The expression BW —α 0·363LS + 0·057P is a simplified multiple regressional form involving BW, LS and parity (P) where a varies according to breed, herd and age of the doe. The estimate of a for kids from British Saanen, 1-year-old does in Herd 1 was 3·879 (s.e., 0·632) kg.
The effect of trenbolone acetate on growth rate and carcass composition of young female rabbits
Authors: Lobley G. E. , Walker A. , Connell Alexmary , Galbraith H. 
Published: September 2010

ABSTRACT1. Eighteen New Zealand White × Califomian young female rabbits (does) were paired by weight and age and, at 800 g live weight, placed on a restricted intake based on the mean body weight of each pair. On attaining 1 kg one of each pair was then given 10 mg trenbolone acetate by injection on days 1, 3 and 5 of each week. This continued until the animals reached 2·3 to 2·4 kg (5 to 6 weeks).2. There were no differences in digestible or metabolizable energy intakes between treated and untreated rabbits. However, the treated animals showed small but significant increases in rates of gain for live and empty body weight compared with control does. Treated animals also had significantly more nitrogen (P < 0·001) and less energy (P < 0·05) per unit empty body weight than controls. Although the proportion of total nitrogen retention was 0·19 greater (P < 0·001) in treated does, total energy retention was only slightly less. Treated animals had approximately 40 g (200 g/kg) less fat and 50 g more protein (N × 6·25) than control does at the end of the trial.3. Increases in liver weight and clitoral size were observed in treated animals.
The influence of boar-related odours on puberty attainment in gilts
Authors: Kirkwood R. N. , Hughes P. E. , Booth W. D. 
Published: September 2010

ABSTRACTThree experiments employing 40, 39 and 15 Large White × (Landrace × Large White) gilts respectively were carried out to investigate possible primer pheromone activity (i.e. regulating endocrine systems) for those 16-androstene steroids with known signalling pheromone activity (i.e. immediate behavioural effects) in the pig. Experiment 1 consisted of groups of prepubertal gilts exposed to one of the following odour sources (a) 5α-androstenone (5α-androst-16-en-3-one), (b) 3α-androstenol (5α-androst-16-en-3α-ol), (c) a mixture of both steroids, and (d) a diethyl ether extract of boar submaxillary salivary gland. Age at the onset of puberty in these gilts was compared with that in an unstimulated control group. Experiment 2 was similar to Experiment 1 except that the steroids were used at a higher concentration (100 fold), and a fifth group of gilts was exposed to an intact boar. In the third experiment, age at the onset of puberty was noted following exposure of groups of gilts to one of the following (a) a castrated boar which had received long term injections of testosterone, (b) urine from an intact boar, (c) an intact boar.The results confirmed that the intact boar accelerates puberty in gilts. Although there was no conclusive evidence indicating that isolated boar odours had an effect on the onset of puberty, it is noteworthy that of those gilts exposed to 3α-androstenol, more reached puberty earlier than control gilts. However there is the possibility that transportation may have enhanced the earlier puberty found in some of the gilts taken to a source of 3α-androstenol. Prolonged treatment of a castrated boar with testosterone did not maintain its ability to accelerate puberty in gilts.
The interaction between dietary fibre level and protein degradability in dairy cows
Authors: Garnsworthy P. C. 
Published: September 2010

ABSTRACTA trial was performed to investigate the interaction between energy and protein source for cows in negative energy balance. Six cows were assigned to each of four types of concentrate (metabolizable energy (ME) 12 MJ/kg dry matter (DM), crude protein (CP) 180 g/kg DM) with low or high fibre contents (LF or HF) and protein degradability (LD or HD). For groups HDLF, LDLF, HDHF and LDHF respectively, acid-detergent fibre contents (g/kg diet DM) were 69·2, 66·1, 117·5 and 113·3; protein degradability values were determined as 0·78, 0·61, 0·72 and 0·66. Low-fibre diets were given at the rate of 11 kg/day concentrates with 6 kg/day hay (ME 8 MJ/kg DM, CP 84·5 g/kg DM) and high-fibre diets at the rate of 10 kg/day concentrates with 7·5 kg/day hay from weeks 4 to 13 of lactation. Cows were given a standard diet over the first 3 weeks of lactation and performance in week 3 was used as a covariate.Milk yield was not affected by treatment but the butterfat content of milk from cows given the high-fibre diets (44·9 g/kg) was higher than the low-fibre diets (36·4 g/kg; P < 0·01), which resulted in significant differences in fat-corrected milk yield (HDHF: 25·1, LDHF: 26·2, HDLF: 22·7, LDLF: 21·5, s.e.d. 1·5 kg/day). ME balance was lower for the LDHF group (−4·1 MJ/day) than for groups LDLF and HDLF (-15·4 and -16·8 MJ/day; P < 0·05) but was not significantly different from the HDHF group (-29·4 MJ/day). Undegradable protein (UDP) balances were 53·4, 93·8, -21·2 and 193·8 (s.e.d. 45, P < 005) g/day for groups HDLF, LDLF, HDHF and LDHF respectively. Differences from zero in ME and UDP balance were accounted for in all groups except LDHF by changes in live weight plus a systematic correction of approximately 10 MJ/day. It is considered that the cows given high-fibre diets responded to high UDP by increasing fat-corrected milk production but mobilization of body fat to support this increase was accompanied by retention of protein with associated water, resulting in very little change in live weight. It is also probable that the high UDP levels improved the digestion of fibre i n the rumen, but this is unlikely to have been sufficient to have accounted for all of the response.
Components of environmental variance of yields of cows in different lactations
Authors: Brotherstone Susan , Hill W. G. , Thompson R. 
Published: September 2010

ABSTRACTWith a view to incorporating identifiable environmental factors such as month of calving as random effects in models for dairy sire and cow breeding value estimation, an analysis was undertaken of environmental components of variance for fat yield in lactations 1 to 5 of pedigree British Friesian-Holstein cattle. Records of fat yield and of log fat yield on daughters of widely used sires were first corrected for age and month of calving and for sire in each lactation on a national basis. Variance components for herd-year, herd-year × lactation, herd-year × month of calving, herd-year × month of calving × lactation and error were then estimated for pairs of lactations.The results were most consistent for log fat yield, where heterogeneity of variance was less. Correlations were, approximately, 0·45 and 0·42 for records in the same herd-year and lactation for lactation 1 or a later lactation, respectively, and approximately 0·40 for records in the same herd-year and different lactations. Within herd-year and lactation, correlations of records in the same month were approximately 0·10 for lactation 1 and 0·08 for later lactations, and for different lactations the correlations were 0·06 if lactation 1 was included and 0·08 otherwise. Thus, the effects appear to be similar for later lactations, which can be pooled, but effects for month and month × lactation 1 v. later should be fitted.
The effect of supplementary light on the production and behaviour of dairy cows
Authors: Phillips C. J. C. , Schofield S. A. 
Published: September 2010

ABSTRACTIn experiment 1, 12 cows (treatment L) received natural daylight (mean 8 h), 10 h supplementary light (mean intensity 481 lux) and dark (mean 6 h), and 12 cows (treatment N) received natural daylight (mean 8 h) and dark (mean 16 h) for 8 weeks. Supplementary light increased milk yield and tended to increase food intake and loss of live weight. There were no significant effects on milk composition although milk fat concentration tended to be reduced for cows in treatment L. Daily feeding times were not affected by treatment although more feeding took place during the supplementary light in treatment L. Supplementary light increased the time spent lying down per day and reduced the distance walked per day, although cows in treatment L spent less time lying during the light supplementation period. In both treatments, the activity rate was increased on the day of oestrus, but in treatment L the incidence of oestrus-specific behaviour was significantly reduced compared with treatment N.In experiment 2, 16 cows received natural daylight (mean 9 h) and 10 h supplementary light of mean intensity 0, 101, 191 or 529 lux in a change-over design. There were no significant effects of supplementary light or its intensity on the food intake, milk yield or live-weight change of the cows, but milk fat concentration was reduced for cows receiving supplementary light at 101 or 529 lux and milk protein concentration was reduced for cows receiving light at 529 lux.
Non-parametric lactation curves
Authors: Elston D. A. , Glasbey C. A. , Neilson D. R. 
Published: September 2010

ABSTRACTLactation curves are fitted to data as a preliminary to estimating summary statistics. Two widely quoted curves are atbe-ct (Wood, 1967) and a(1 - e-bt) - ct (Cobby and Le Du, 1978), each of which has three parameters. Restriction to either of these curves imposes limitations on the fit to the data and can result in biased estimation of summary statistics. Alternatively, lactation curves can be generated by the use of a non-parametric method which requires only weak assumptions about the signs of derivatives of the curves. Because the non-parametric curves are more flexible, estimates of summary statistics are less likely to be biased than those based on parametric models. Use of the non-parametric curves is particularly advantageous around the time of peak yield, where the curves of Wood and Cobby and Le Du are known to fit data poorly.
Growth and carcass composition of Friesian, Limousin × Friesian and Blonde d'Aquitaine × Friesian steers
Authors: Keane M. G. , More O'Ferrall G. J. , Connolly J. 
Published: September 2010

ABSTRACTOne hundred and twenty spring-born steers comprising 40 Friesians (FR), 40 Limousin × Friesians (LM), and 40 Blonde d'Aquitaine ' Friesians (BL), were reared together from shortly after birth to slaughter at a mean age of 771 days. They were at pasture in summer and were housed and offered grass silage plus concentrates in winter. All were implanted with anabolic agents. During the finishing winter, there was a 3 (breed types) ' 2 (3 or 6 kg concentrates per day) ' 2 (94 or 181 day finishing period) factorial arrangement of treatments.Slaughter weights per day of age, carcass weights per day of age and carcass weights of FR, LM and BL were 846, 828 and 866 (s.e. 8·0) g, 464, 476 and 497 (s.e. 4·9) g and 358, 368 and 385 (s.e. 3·8) kg respectively. LM had lower carcass length, carcass depth, leg length and leg width values than FR or BL but when these measurements were expressed per kg carcass weight the values for LM and BL were similar. Both LM and BL had better carcass conformation than FR, and BL had a lower carcass fat score than either FR or LM between which there was no difference. FR, LM and BL had carcass lean, fat and higher-priced lean proportions of 634, 669 and 685 (s.e. 3·7), 185, 168 and 144 (s.e. 3·7) and 352, 361 and 361 (s.e. 1·4) g/kg respectively.Increasing the concentrate level from 3 to 6 kg per day increased side weight by 9·6 kg (P < 0·001). This consisted of 0·6 kg bone, 3·3 kg lean and 5·7 kg fat. Extending the finishing period from 94 to 181 days increased side weight by 30·3 kg (P < 0·001). This consisted of 2·6 kg bone, 12·0 kg lean and 15·7 kg fat. Allometric regression coefficients for side lean, bone and fat weights on side weight were not significantly affected by breed type or concentrate level. The coefficients for lean, bone and fat were 0·80 (s.e. 0·04), 0·58 (s.e. 0·05) and 2·27 (s.e. 0·16) respectively. The coefficients for weights of lean in the hind-shin, fore-shin, fillet and brisket on side lean weight were 0·8 or lower. The corresponding coefficients for silverside, inside round, knuckle, rump and strip-loin were between 0·8 and 1·0 while the flank, shoulder, neck, chuck, plate, fore-rib and cube-roll had coefficients in the range 1·0 to 1·5.
The effect of beta-adrenergic agonists on carcass and meat quality in sheep
Authors: Warriss P. D. , Kestin S. C. , Brown S. N. 
Published: September 2010

ABSTRACTTwenty-four crossbred wethers (live weight 27·6 (s.e. 0·36) kg) were divided into three groups and given a concentrate diet. One group was a control, one was given cimaterol (10 mg/kg diet) and one was given clenbuterol (2 mg/kg diet). After 49 days on treatment the animals were fasted for 48 h and slaughtered at a live weight of about 36 kg. The effects of both beta-agonists were similar. Food conversion was proportionately 0·20 better in treated sheep which also produced heavier (18·3 v. 17·0 kg, P < 0·01) carcasses that were leaner. The cross-sectional area of the m. longissimus was increased proportionately by about 0·25 (P < 0·001) and the thickness of subcutaneous fat over the muscle reduced by 0·37 (P < 0·01). The loin joint from treated animals contained proportionately 0·30 more muscle (P < 0·001) and 016 (F > 0·01) less fat. Muscles from treated sheep had higher pHu values (P < 0·01) which resulted in reduced loss of exudate during storage (P < 0·01) and darker colour (P < 0·05). They also contained only about half as much intramuscular fat (13 v. 27 mg/g, P < 0·001) and less haem pigments (2·4 v. 3·9 mg/g, P < 0·001). The results indicate that beta-agonists substantially improve carcass quality but, under certain conditions of pre-slaughter handling, may reduce lean meat quality. The similarity of response to both beta-agonists suggests the observed effects on meat quality may be common to this class of drug.
The effect of pre-mating nutrition and exposure to the presence of rams on the onset of puberty in Awassi ewe lambs under semi-arid conditions
Authors: Kassem R. , Owen J. B. , Fadel I. 
Published: September 2010

ABSTRACTTwo experiments are described investigating the possibility of advancing puberty in Awassi ewe lambs kept under semi-arid conditions in mid Syria using 197 single ewe lambs in 1982 and 165 in 1984. In both years, the animals were allocated to three groups each given different levels of supplementation with a barley/chopped straw mixture to achieve different levels of pre-mating growth (high, medium and low). In 1984, the three groups were further subdivided into four subgroups each given continuous exposure to teaser rams from different ages. These were 175, 200 and 230 days of age and a control group not given continuous access to the ram. The results for the two experiments showed that a higher proportion of ewe lambs on the high and medium treatments showed oestrus in their first season (H = 88%, M = 72%, L = 41%; P < 0·01). The high level of nutrition also advanced the mean date of first oestrus in the high group by 22 and the age at conception by 16·5 days as compared with the low level.In the second experiment, no interaction between feeding level and presence of ram was observed and although there were no significant effects on occurrence of oestrus, continuous exposure to vasectomized rams from 175 days reduced mean age at first oestrus by 16 and age at conception by 19 days as compared with the unexposed controls.It is concluded that these practices have important implications for the efficient use of semi-arid range land by Awassi sheep on a semi-intensive system.
Effect of diet and of remating interval on milk production and milk composition of the doe rabbit
Authors: Fraga M. J. , Lorente M. , Carabaño R. M. , de Blas J. C. 
Published: September 2010

ABSTRACTThe influence of four diets and two remating intervals (1 or 9 days after parturition) on several milk and production traits was studied in 73 lactations of 46 Californian C? × New Zealand $ does. Three diets were formulated to provide increasing levels of fibre concentration (180, 202 and 238 g acid-detergent fibre per kg dry matter (DM)); a fourth diet contained added pork lard (35 g/kg) at the lowest level of fibre. The energy: protein ratio was maintained between 72 and 84 kj digestible energy (DE) per g digestible protein.The DE intake increased significantly when fat was included in the diet but was not affected by dietary fibre concentration. An increase in the DE content of the diet tended to decrease food conversion ratio at a mean rate of 0·16 kg/kg per MJ/kg DE. Fat addition also improved milk yield, litter weight at 21 days and survival index, mainly when litter size was higher than nine pups born alive. Neither live-weight gain nor prolificacy of does were affected by any of the variables studied.The type of diet did not affect milk DM, crude protein, fat and energy concentrations, the mean values being 287·8, 116·1, 134·2 g/kg and 27·73 MJ/kg, respectively. The proportions of short- and medium-chain fatty acids in milk fat were not affected by type of diet. The effect of fat addition on milk fat composition was limited to the long-chain fatty acids, mainly C18: 0 and C18: 1. These changes in addition to differences in milk intake could also affect the survival index of pups.Does remated 1 day after parturition showed a lower total milk yield than those remated 8 days later, the decrease being more apparent at the end of lactation. Remating interval did not affect the other variables studied.
Effects of protein concentration in the diet on milk yield, change in body composition and the efficiency of utilization of body tissue for milk production in ewes
Authors: Cowan R. T. , Robinson J. J. , McHattie I. , Pennie K. 
Published: September 2010

ABSTRACTTwenty-five mature Finnish Landrace × Dorset Horn ewes, each suckling two lambs, were used to measure the effects of dietary concentration of crude protein on food intake, milk yield and changes in body composition during the first 6 weeks of lactation. Diets were complete mixes of milled hay and concentrates, and the amounts of barley and fish meal were altered to give crude protein concentrations of 116 and 143g/kg dry matter. Ten ewes were slaughtered at 5 to 7 days of lactation and the remaining ewes were slaughtered at 40 to 43 days of lactation.The higher concentration of crude protein in the diet did not alter food intake or digestion. Milk yield was not altered in the first 3 weeks of lactation but was increased in weeks 4 and 5 (P<0·05). Production of milk protein was increased by a higher protein concentration in the diet (P<0·01) and this effect was evident from the 2nd week of lactation. Weight of chemically determined fat in the body decreased from 179 to 13-0kg from 6 to 42 days of lactation (P<0·001) for ewes on diets of both concentrations of crude protein.It was concluded that the higher level of protein intake during early lactation increased yields of milk and milk protein. The data suggest that the energy lost from the body was used more efficiently by ewes given the diet of high, rather than low, protein content.
Response of Slovak Spotted cattle to stresses evoked by physical stimuli and the administration of pharmaceutical agents
Authors: Jedliĉka J. , Mojto J. , Vanĉiŝin J. , Kmetová E. , Páleník S. 
Published: September 2010

ABSTRACTNine bulls of the Spotted Slovak breed were exposed to different stressful stimuli. The stimuli used were noise, electric shock and the administration of insulin, adrenocorticotrophic hormone and the sedative xylazine (Rompun). The levels of glucocorticoids, free fatty acids and glucose were determined in blood samples obtained through a permanent, indwelling, jugular cannula. It was found that insulin, adrenocorticotrophic hormone and electric shock evoked significant increases in the concentration of glucocorticoids in the blood. Noise did not affect the blood level of glucocorticoids. The stimuli did not induce any change in the blood levels of free fatty acids. Blood glucose levels were increased following insulin, adrenocorticotrophic hormone, electric shock and xylazine but not following noise. Insulin, as expected, decreased the concentration of glucose in the blood.
A note on the relationship between litter size at birth and litter weight at weaning in domesticated and feral mice
Authors: Congleton W. R. 
Published: September 2010

ABSTRACTThe relationship between litter size at birth and litter weight at weaning is curvilinear, with an intermediate litter size resulting in the heaviest litter weight at weaning. Relative to feral mice, the mean and variation for litter size at birth was larger for domesticated mice which had been selected for fertility and crossbred. Consequently, some of the litters from the crossbred domesticated mice were larger than the litter size at birth which optimized litter weight at weaning, primarily due to increased pre-weaning mortality. If litter weight at weaning is to be optimized by indirect selection for litter size at birth, the variation around an intermediate optimum litter size at birth could be most effectively reduced by negative assortative mating.
The effect of different levels of management on the assessment of differences between varieties of chickens. 1. Eight-week body weight
Authors: Bowman J. C. , Powell J. C. 
Published: September 2010

1. Analyses of records of eight-week body weight in broiler chickens have been carried out to estimate the effect of management level (measured by mean body weight of all varieties on each farm) on the components of variance due to differences between and within varieties, and to find out if there is any evidence of genotype-environment interaction.2. It was found that as management improved, the between-variety genetic variance remained constant or possibly increased whilst the withinvariety (genetic and environmental) variance decreased markedly. The cause of these regressions is not known.3. In four cases out of six there were significant genotype-environment interactions. In two cases, the genetic correlation between the performance of varieties on different locations was significantly different from 1·0.4. It is suggested that on the basis of these findings it would be necessary to select between varieties on records taken from chickens maintained under conditions similar to those in which they will eventually be used. However, fewer chickens would be required to measure, with a predetermined level of accuracy, mean differences on well managed farms than on poorly managed ones.