bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of plane of nutrition, live weight, temporary weaning and breed on the occurrence of oestrus in beef cows during the post-partum period
Authors: Holness D. H. , Hopley J. D. H. , Hale D. H. 
Published: September 2010

ABSTRACTThe occurrence of oestrus and ovarian function during the post-partum period was examined in 160 lactating beef cows of the Africander and Mashona breeds. Cows were fed either to gain 12 to 14% (High) or to lose 12 to 14% (Low) of their autumn peak live weight (early pregnancy) by mid-breeding season. Half the cows in each group were subjected to an increase (Low-High) or decrease (High-Low) in nutrient intake for a 25-day period starting at 25 days partum. Nursing was interrupted for an 8-day period in half of the cows at 50 days post partum by the application of nose plates to their calves.Oestrus occurred significantly earlier in the high than the low plane cows (66 v. 75 days post partum respectively, P< 0·05), but short-term fluctuations in nutrient supply had no apparent effect on the incidence of oestrus. Temporary weaning significantly reduced the mean time from calving to first oestrus in the high-plane (P< 0·01) but not in the low-plane cows, and in Mashona (P<0·05) but not in Africander cows. There was a lower incidence of ‘silent’ oestrus and the mean occurrence of oestrus was significantly earlier (P< 0·001) in the Mashona when compared with the Africander cows.
Fertility in Cheviot ewes. 1. The effect of body condition at mating on ovulation rate and early embryo mortality in North and South Country Cheviot ewes
Authors: Gunn R. G. , Doney J. M. 
Published: September 2010

ABSTRACTIn two experiments over 2 years, 113 North Country Cheviot and 132 South Country Cheviot hill ewes were differentially group-fed over a 10-week period to achieve either good or moderate body con- dition. Ewes were maintained in these levels of condition over the 5 weeks prior to mating. After mating, ewes were killed either on return to service or between days 23 and 85 for counts of corpora lutea and viable embryos.Ovulation rate in each breed was positively related to body condition at mating. Embryo mortality, as ova loss, was not influenced overall by breed, type of ovulation, year of recording, or body condition. Although comparisons of loss were partly confounded by a differen- tial distribution in the number of ova shed in each breed and body condition group, there was an apparent breed difference in loss of single- and multiple-shed ova. Potential lambing rate therefore showed greater response to improved body condition at mating in the North Country Cheviot breed than it did in the South Country Cheviot.
Fertility in Cheviot ewes. 3. The effect of level of nutrition before and after mating on ovulation rate and early embryo mortality in South Country Cheviot ewes in moderate condition at mating
Authors: Gunn R. G. , Doney J. M. , Smith W. F. 
Published: September 2010

ABSTRACTOne hundred and twenty South Country Cheviot hill ewes were differentially group-fed indoors over a 2-month period to achieve either moderately-good or poor body condition. Over 5 weeks prior to mating, ewes in moderately-good condition were brought down in condition by restricted feeding and ewes in poor body condition were raised in condition by a high level of feeding. The ewes were thus in moderate condition at mating. During the first 4 weeks after mating, half the ewes from each original condition group were fed at a high level and the other half were fed at a low level. Ewes were killed either on return to service or at 30 ± 10 days forcounts of corpora lutea and viable embryos.Ovulation rate was not significantly related to the level of pre-mating food intake at the condition level studied, although the trend was positive. Embryo mortality, as ova loss, was reduced by a high level of post-mating food intake but was increased by a high level of pre-mating intake. This latter result, however, may be influenced by the experimental confounding of high pre-mating food intake and very low initial body condition. The greatest loss was incurred by ewes, originally in poor condition, which were fed at a high pre-mating level and a low post-mating level. Potential lambing rate at slaughter was not affected by the level of food intake either before or after mating although the trend was for a low level of post-mating intake to be associated with an increase in the proportion of barren ewes.
The performance of Masham ewes
Authors: Newton J. E. , Fenlon J. S. 
Published: September 2010

ABSTRACTThe performance of two flocks of crossbred Masham ewes (Tees-water × Dales Bred) was measured for 6 and 4 years respectively. The ewes in Flock 1 were mated with Dorset Down rams and the ewes in Flock 2 with Suffolk rams.The overall mean mating weight of each flock was 68-0 kg with no consistent year-to-year variation. The mating weight repeatability values for ewes entering the flocks as 2-year-olds were 0·532 (±0·0681) and 0·524 (±0·1118) for Flocks 1 and 2 respectively.Mean litter size increased with age, but repeatability was low. Over- all litter weights for singles, twins and triplets were 5·89, 9·88 and 12·43 kg respectively. Two-year-old ewes had lighter litters than mature ewes. Repeatability for litter weight in Flock 1 was 0·337 (±0·0755).Lamb growth rate to 4 weeks of age was lower for 2-year-old ewes in both flocks and the repeatability was 0·322 (±0·0947) in Flock 1. For ewes having twin lambs, significant correlations (P < 0·01) were found between mating weight and birth weight and between birth weight and lamb growth rate to 4 weeks of age.Perinatal mortality was higher for lambs with a birth weight below 3·9 kg, but overall lamb mortality was only 8%: this low figure was probably due to the relatively high birth weight of the twin and triplet lambs.
The effect of copper treatment on the performance of hypocupraemic calves
Authors: MacPherson A. , Voss R. C. , Dixon J. 
Published: September 2010

ABSTRACT1. Seven experiments involving 191 calves and 40 cows were under- taken over a 2-year period into the effect of copper treatment of hypocupraemic calves on their subsequent performance.2. Significant increases in mean live-weight gain of copper-treated calves ranging from 19·9 to 34·3 kg/head relative to untreated control groups were obtained in three cases.3. The frequency of copper injection required to maintain plasma copper levels above 0·60 mg/1 varied from 6 to 12 weeks.4. The live-weight gain and plasma copper concentration responses are discussed in relation to the pasture herbage concentrations of copper, molybdenum and sulphate.
Feeding calcium salts of fatty acids in high-starch or high-fibre compound supplements to lactating cows at grass
Authors: Garnsworthy P. C. 
Published: September 2010

ABSTRACTIn two experiments, the effects of protected fat and fibre were studied in compound supplements for grazing dairy cows. The protected fat used consisted of calcium salts of long-chain fatty acids. In experiment 1, 17 cows (group S) were given 4 kg/day of a starchy compound and 17 (group F) 4 kg/day of a high-fibre compound containing protected fat for the first 4 weeks after turn-out to grass. No significant difference was found between groups in milk yield, but cows in group F produced milk with a higher fat content (42·6 g/kg) than did those in group S (37·1 g/kg; P < 0·01) and had higher yields of fat (0·88 v. 0·79 kg/day; (P < 0·05). In experiment 2, four groups of five cows were given 4 kg/day of starchy (S) or fibrous (F) compounds, with (P) or without (C) protected fat for the first 4 weeks after turn-out. After 4 weeks, treatments (starchy or fibrous, added fat or none) were reversed for a further period of 4 weeks. There was no significant effect on milk yield, milk protein yield, live-weight change or change in condition score, although cows on treatment SC tended to produce less milk and have greater gains in live weight and condition. For groups SC, FC, SP and FP respectively, milk fat yields (kg/day) were 0·86, 0·98, 0·99 and 1·06 (s.e.d. 0·06); milk protein contents (g/kg) were 34·4, 34·8, 34·2 and 33·0 (s.e.d. 0·68) and calculated milk energy outputs (MJ/day) were 67/2, 74·3, 74·4 and 76·6 (s.e.d. 3·04). It is concluded that substituting fibrous compounds for starchy compounds tends to increase milk fat content and yield; adding calcium salts of fatty acids to either type of compound significantly increases milk fat content and yield but tends to decrease milk protein content.
Selection and response within the nucleus of a sheep group-breeding scheme
Authors: Anderson S. , Curran M. K. 
Published: September 2010

ABSTRACTAn evaluation of the response to selection for prolificacy within a nucleus sheep flock of a commercial group-breeding scheme is presented. In 1979, the Romney Group Breeders formed a nucleus flock of 120 prolific ewes chosen from 12 contributing flocks. A control flock was established in 1982 from the same source. The analysis was conducted on the trait of litter size. Selection differentials are presented for each year of birth progeny group in both flocks. Expected selection response was calculated from selection differentials and was found to have an average value of 1·5% of parent mean litter size per year. Using least squares procedures the litter size performance of control and nucleus ewes of 2, 3 and 4 years of age was corrected for environmental effects. Realized response was estimated from the differences between corrected litter size means of control and nucleus flocks. Response in litter size was found to be significant within years and within ewe age groups (P < 0·05).
Compensatory growth and body composition changes in grazing steers following silage feeding without or with a supplement of fish meal and monensin
Authors: Gibb M. J. , Baker R. D. 
Published: September 2010

ABSTRACTThe effects of fish meal and monensin supplementation of silage on the growth and composition Friesian steers was examined in winter and subsequently during grazing. Four-month-old steers were given grass silage ad libitum, alone (U) or mixed with fish meal and monensin at 100 and 0·005 g/ dry matter (DM) of silage (S) for 17 weeks. Empty body weight (EBW) and carcass weight (CW) gains were significantly increased by supplementation (810 v. 495, and 553 v. 332 g/day, respectively). Although treatment S steers were heavier, their composition at turn-out was similar to that of the treatment U animals: mean fat, crude protein (CP), water, ash and energy contents were 121, 187, 640, 51 g/kg and 9·10MJ/kg EBW, respectively. During the following 20 weeks, six animals from each treatment grazed a perennial ryegrass/white clover sward unsupplemented (UU and SU), supplemented with a fish meal/maize/molassine meal (50:35: 15) pelleted diet and monensin at 4 g/kg live weight (LW) per day and 0·1 mg/kg LW per day, respectively, (UMF and SMF). A further group of six steers from treatment S received the pelleted diet without monensin during grazing (SF). Steers from treatment U showed significant compensation in EBW and in carcass growth at pasture, irrespective of whether they received a supplement, which led to a marked reduction of the differences in EBW and CW by final slaughter. Composition at final slaughter showed no significant effect winter nutrition, with the exception of fat content (g/kg EBW), which was significantly lower animals from treatment SU. Steers from treatments UMF and SMF had slightly higher rates of fat, CP, water and energy deposition, which resulted in higher fat and lower water contents (g/kg EBW) than those from treatments UU and SU, although these differences were not significant. Steers on treatment SF had gains and final compositions intermediate between those on treatments SU and SMF. Supplementation was cost effective in winter, but marginal in summer.
Influence of trenbolone acetate, zeranol and oestradiol-17β implantation on growth performance and reproductive function in beef heifers
Authors: Zarkawi A. , Galbraith H. , Hutchinson J. S. M. 
Published: September 2010

ABSTRACTTwenty-four Hereford ♂ × Friesian ♀ heifers were divided into four equal treatment groups and given subcutaneous ear implants as appropriate 14 days after prostaglandin treatment for the induction of synchronized cycles. Subsequently, they were observed for 75 days. One group was an untreated control, one was given 300 mg trenbolone acetate, one 36 mg zeranol and one 45 mg oestradiol-176. Growth and ovarian cyclicity, assessed by periodic progesterone measurement, were monitored. Trenbolone acetate-treated heifers grew faster (P < 0·05) than other groups which did not differ significantly. Trenbolone acetate shortened the oestrous cycle in which treatment was started in two of five heifers and lengthened it in two others. Subsequent cycles were either suppressed or of short duration. Zeranol and oestradiol-176 treatment had little effect on ovarian cyclicity apart from a small increase in the number of short cycles. It is concluded that, at the doses used, trenbolone acetate suppresses mechanisms leading to ovulation or pre-ovulatory follicular development.
Seasonal variation in voluntary food intake and post-weaning growth in lambs: a comparison of genotypes
Authors: Iason G. R. , Mantecon A. R. 
Published: September 2010

ABSTRACTVoluntary food intake (VFI) was measured daily and live weight (LW) was measured weekly in a total of 39 growing lambs of six genotypes given a similar complete chopped-straw based diet in experiments in 1983, 1985, 1987 and 1988. The six genotypes and the years of study were: Scottish Blackface (BF), 1983 and 1988; Suffolk × (Border Leicester × BF) (BL × BF), Suffolk × (East Friesland × Cheviot) (EF × NCC), Suffolk × (East Friesland × BF) (EF × BF), 1985; Welsh mountain (WM) and Beulah (BH), 1985. Measurements were made on lambs penned individually within 6 weeks of weaning at 5 to 6 months of age through to slaughter in the following spring. During this period there was an increase in LW and VFI associated with growth. Regression lines were fitted to LW and weekly means of daily VFI against week for each individual. Analysis of deviations about these lines showed a decline in VFI in BF lambs around December and to a lesser e×tent in BL × BF from December to January. The decline in VFI in BF was observed in two different years. A negative deviation from the normal rate of increase in LW was also apparent although it was much less marked and present in EF × NCC lambs as well as BF and BF × NCC. Any such variability of seasonal cycles between genotypes of growing lamb would influence the e×tent to which nutrition and growth may be manipulated. This should be considered when choosing a feeding or growth regime for a particular genotype, or vice versa.
Comparative aspects of resistance to body cooling in newborn lambs and kids
Authors: Müller S. , McCutcheon S. N. 
Published: September 2010

ABSTRACTThe aim of this study was to compare responses to cold stress in newborn lambs and kids. Two experiments were conducted in a climatic chamber with controlled air temperatures and artificial wind and rain. The first experiment involved 25 Poll Dorset × (Border Leicester × Romney) lambs and 16 Angora × feral kids while the second involved 30 Suffolk × (Border Leicester × Romney) lambs and 26 Angora × feral kids. Rectal temperatures were measured and the rate of decline in rectal temperature estimated in both experiments. In the second experiment, metabolic rate was also measured and coat characteristics (birth coat depth and wool weight per unit area of skin) were examined. The effects of birth rank and sex on resistance to cold exposure and their interaction with species were examined in both experiments.In experiment 1, kids had lower rectal temperatures than lambs at the start of the test but there was no species effect on the rate of decline in rectal temperature. In experiment 2, kids exhibited a significantly greater rate of decline in rectal temperature than did lambs. This difference in species effect between the experiments reflected primarily a greater rate of body cooling in the Poll Dorset-cross lambs (experiment 1) than in the Suffolk-cross lambs (experiment 2) rather than a difference between the kids in the two experiments. Additionally, in experiment 2, metabolic rate per unit live weight was significantly lower in the kids than in the lambs. No differences were apparent between the species in coat characters. Multiple-born lambs and kids were found to exhibit a significantly greater rate of decline in rectal temperature than singles, but only marginal differences in heat production were observed between the birth ranks. No significant effects of sex on resistance to cold stress were found in this study. Effects of birth rank and sex were additive with those of species. It is concluded that a combination of low heat production capacity and small body size is responsible for the generally poor responses of newborn kids to cold stress but there is probably little difference between lambs and kids in the insulative value of their birth coats.
Prediction of voluntary intake of grass silages by lactating cows offered concentrates at a flat rate
Authors: Rook A. J. , Gill M. , Willink R. D. , Lister S. J. 
Published: September 2010

ABSTRACTData for individually recorded silage dry-matter intake (SDMI), concentrate dry-matter intake (CDMI), live weight, milk yield and milk composition of lactating dairy cows offered silagead libitumand concentrates on a flat-rate basis, together with data for silage composition from experiments conducted at four sites, were used to obtain simple and multiple regressions of SDMI on other variables.Simple regressions showed that the most important variables affecting SDMI were, in order of importance: silage ammonia nitrogen, fat yield, CDMI, silage digestible organic matter concentration (DOMD) and live weight. The best multiple regression for the mean SDMI over weeks 4 to 13 of lactation accounted for proportionately 0·649 of the variation. Examination of week by week data for weeks 3 to 20 of lactation showed that two models for early and mid lactation were required to give a reasonable pattern of residual variances. These models accounted for 0·627 and 0·581 of the variation respectively. It was necessary to fit time effects explicitly in early lactation. Live weight was best represented by fitting post-calving live weight and deviations from post-calving live weight separately. A number of models requiring fewer input variables were also obtained to allow for use in situations where the full range of measurements is not made.The new models were tested using independent data from three sites. They performed better than a number of previously published models but the best model still gave a prediction error of proportionately 0·17 about the mean actual silage intake in early lactation and 015 in late lactation.The results suggest that there is little to be gained from further refinement of the functional form of the models and that the construction of a number of models for specific food and management situations is preferable to the use of global models.
The utilization of alkali-treated wheat straw: effects of neutralization of residual alkali and potassium supplementation on growth and mineral balance of male calves
Authors: Holzer Z. , Drori D. , Brosh A. , Levy D. 
Published: September 2010

ABSTRACTThe mineral balance of male calves given neutralized (with HC1) and unneutralized 35 g NaOH per kg treated wheat straw (WS), was determined in a digestibility trial in which WS was offered at inclusion levels of 300, 500 and 700 g/kg diet. The ratio of apparently retained sodium (Na) and potassium (K) increased with increasing proportion of straw in the diet and was lower on neutralized straw diets.The effect of supplementation with 3 and 6 g K per kg diet dry matter in a diet comprising approximately 500 g/kg of 35 g NaOH per kg treated WS, on performance, mineral status and acidbase balance was examined in a growth trial with 56 Israeli-Friesian male calves. The animals on the untreated WS diet had significantly (P< 0·05) less fat in the large depots and lower fat trim of carcass than did animals on the treated WS diets. No other differences in performance were significant. Ammonia concentration in rumen liquor and urea in blood were lower in the animals given alkali-treated WS. The concentrations of Na, K and chlorine in blood serum of the experimental animals were not affected by the treatment. The data on Na, K and magnesium (Mg) in muscle show depletion of Na and K and a trend towards a decrease in Mg concentration. K supplementation reduced the extent of depletion of Na and K. In bone, only Na was affected by the feeding of alkali-treated WS, the pattern being the same as in the muscle. The blood acid-base balance of the experimental animals was not significantly affected by treatments. The values of pH, actual bicarbonate and pCO2 of the animals given 35 g/kg alkali-treated WS indicate mild alkalosis in those animals. This alkalotic state did not affect performance. It appears that there is no Na loading problem which might interfere with growth.
Influence of straw quality and level of concentrate in a completely mixed diet on intake and growth rate in steers
Authors: Ørskov E. R. , Reid G. W. , Kay M. 
Published: September 2010

ABSTRACTThree types of straw were used, a spring barley (variety Corgi) untreated (UC), ammonia-treated Corgi (AC) and an ammonia-treated winter wheat (variety Longbow) (AW). Each straw was included in a complete diet containing either 350 (L), 450 (M) or 550 (H) g/kg straw. The other principal ingredients were rolled barley, molassed sugar-beet pulp and fish meal. Hereford cross steers approximately 16 months old and weighing 350 kg live weight were given the diets ad libitum in both a main trial lasting 80 days, to assess intakes, live-weight gains and food efficiency, and in a subsidiary trial to measure in vivo apparent digestibility.The live-weight gains during 80 days for steers given the UC diet at L, M and H inclusion were 117, 102 and 0·70 kg/day respectively. The respective live-weight gains for AC were 1·32, 1·27 and 1 02 kg/day and for AW 1 ·26, 1 ·20 and 0·95 kg/day.While experimental comparisons were terminated at 80 days when the first steers were slaughtered, all except five with the lowest growth rate reached the target fat class for slaughter before 6 months on the diets. While differences in intake and performance between steers given the straws closely reflected differences in degradation characteristics determined by in sacco measurements, the increase in in vivo apparent digestibility between untreated (0·510) and treated (0·545) was small. It is concluded that a large proportion of high quality or treated straw can be incorporated and utilized in diets for finishing cattle.
Influence of social conditions post-puberty on the sexual behaviour of the domestic male pig
Authors: Hemsworth P. H. , Winfield C. G. , Beilharz R. G. , Galloway D. B. 
Published: September 2010

SUMMARYThree groups of four mature boars were housed in individual pens for 3 mo under one of the following social conditions: near ovariectomized female pigs induced into sexual receptivity at 2-week intervals; isolated from female pigs but either with or without visual and physical contact with neighbouring boars. The total number of copulations achieved in six mating tests throughout the period was significantly greater (P<0·01) for the boars housed near sexually receptive females than for those housed in the other two social conditions. For the subsequent 3 mo all boars were housed near sexually receptive females and no significant differences were found between the three groups for total number of copulations.