bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies in sow reproduction 1. The effect of nutrition between weaning and remating on the reproductive performance of primiparous sows
Authors: Brooks P. H. , Cole D. J. A. 
Published: September 2010

SUMMARYFollowing weaning of their first litter at 42 days post partum, 36 Landrace × (Landrace × Large White) sows were fasted for 24 hr then allocated to one of three feed levels, 1·8, 2·7 and 3·6 kg food/day, until the day after mating. During pregnancy all the sows received 1·8 kg food/day.The incidence of infertility and anoestrus was greatest for sows fed 1·8 kg/day and least for sows fed 3·6 kg·day. Sows fed 1·8 kg/day took significantly (P < 0·01) longer (21·6 + 3·0 days) to return to oestrus than sows fed 3·6 kg/day (9·2 ± 2·2 days). The mean litter size for sows fed 1·8, 2·7 and 3·6 kg food/day was 9·4 ± 0·9, 10·1 ± 0·8 and 11·5 ± 0·6 piglets respectively, but these differences were not significant.
The effect of a methane-suppressing compound, trichloroethyl adipate, on rumen fermentation and the growth of sheep
Authors: Clapperton J. L. 
Published: September 2010

SUMMARY1. Three experiments have been carried out to study the effect of adding trichloroethyl adipate, a compound known to prevent the production of methane bothin vitroandin vivo, to the diet of sheep on fermentation in the rumen and on the growth of lambs. In Experiment 1 the additive was incorporated at various levels for 6 weeks, in Experiment 2 it was given at one of four levels for 12 weeks and in Experiment 3 it was included in the food of growing lambs for 15 weeks.2. Initially, in Experiments 1 and 2, the additive caused a large reduction in methane production and in the molar proportion of acetic acid in the rumen liquor with a corresponding increase in propionic acid. These effects were much reduced after the first 2 to 3 weeks of administration.3. The total food intake of the animals receiving the additive in Experiment 3 was 4% less than that of the control animals. This difference was negligible at the start of the experiment but increased throughout the feeding period.4. On average, the relative live-weight gain and the changes in the weights of carcass, viscera and empty body weight of the animals receiving the additive were also 4% less than those of the control animals.5. The observed differences in weight gain resulted from the differences in food intake and the additive had no beneficial effect upon lamb growth. This lack of effect on growth was due to rapid adaptation by the rumen fermentation to the presence of the additive.
A note on the use of brewers' dried grains as a protein feedstuff for cattle
Authors: Öster A. , Thomke S. , Gyllang H. 
Published: September 2010

SUMMARYYoung, uncastrated male cattle (initial weight 80 kg, final weight 240 kg) were used to evaluate brewers' dried grains as a protein source (17 or 36% of the concentrate mixture), in comparison with soyabean oil meal (6% of the concentrate mixture). There were no significant effects on feed intake or average daily live-weight gain. The killing-out percentages for the three treatments were 49·2; 48·6 and 46·9 respectively (P < 0·001). There was a lower fat deposition (P < 0·01) in animals receiving the higher level of brewers' dried grains, and the degree of rumen parakeratosis was less (P < 0·001) with the diets containing grains.
Protein metabolism of rats treated with trienbolone acetate
Authors: Vernon B. G. , Buttery P. J. 
Published: September 2010

ABSTRACT(1) Both the anabolic agent trienbolone acetate (3-oxo-17-β-hydroxy- 4,9,11-estratriene acetate) and testosterone subcutaneously injected into entire female rats caused an increase in growth rate compared with placebo controls (P<0·01 andP<0·001 respectively). The trienbolone acetate rats grew slower than the testosterone-treated animals (P< 0·01). This may reflect differences in the mode of action of the steroids.(2) In castrate males there were no significant differences in growth rate between the trienbolone acetate, testosterone or placebo control rats (P>0·05).(3) Trienbolone acetate reduced the rate of myofibrillar protein degradation in female rats, within 3 days of treatment, at least as judged by Nt-methylhistidine excretion. The treated rats had superior nitrogen retentions (P<0·01) and feed conversions (P< 0·001).(4) The data suggest that the rat is a suitable model on which to test the mode of action of trienbolone acetate.
Anorexigenic substances and voluntary food intake in the pig
Authors: Wyllie D. , Owen J. B. 
Published: September 2010

ABSTRACTThe urine of pigs contains a substance with an anorexigenic effect when injected into pigs or rats. When injected into rats or pigs onad libitumfeeding a urine extract caused a reduction in food intake only when the extract had been obtained from the urine of satiated pigs, and not from hungry pigs. The pig urinary anorexigen there-fore appears to be similar in nature to the anorexigen extracted from rat urine. Like rat urinary anorexigen, its anorexigenic effect is largely dose dependent and it is soluble in distilled water. Rats injected with plasma from satiated pigs showed an anorexigenic reaction but injection of plasma from hungry pigs had no effect on food intake. The possible role of these anorexigenic substances in the control of voluntary food intake in the pig is discussed.
The effect of daylength on the growth of lambs. 1. Comparisons of sex, level of feeding, shearing and breed of sire
Authors: Forbes J. M. , El Shahat A. A. , Jones R. , Duncan J. G. S. , Boaz T. G. 
Published: September 2010

ABSTRACTTwo experiments were carried out with crossbred lambs which had been weaned in July when 16 weeks old. From early September they were kept in a light-proof building with 12 h artificial light per day for 3 weeks and then half were exposed to 16 h and half to 8 h light per day for a further 16 weeks.Experiment 1 included 72 lambs (48 castrated males and 24 females) and half in each daylength were fed on a concentrated ration ad libitum; the other half were restricted to 70 g/kg live weight0·75 per day. Half of each group were shorn. Lambs kept in 16 h light per day grew significantly faster than those in short daylength at both levels of feeding. Food conversion ratio was best in the 16 h restricted sheep. Unshorn lambs had heavier carcasses than shorn lambs. Long daylength stimulated general growth of the animal without markedly affecting carcass composition, irrespective of level of feeding, whereas ad libitum feeding resulted in much fatter carcasses than did restricted feeding. Gut fill was significantly greater in long-daylength sheep.Experiment 2 included 24 individually penned castrated male lambs, 12 of which were sired by Suffolk rams and 12 by Oxford rams; all were fed at the restricted level. Long daylength significantly stimulated weight gain, especially in the Oxford-cross lambs, but the increase in carcass weight was not significant in this experiment due to the large effect on gut fill.It was concluded that long daylength stimulated growth and gut fill by some central control mechanism and not merely by encouraging more eating.
Body composition changes in lactating ewes estimated by serial slaughter and deuterium dilution
Authors: Cowan R. T. , Robinson J. J. , Greenhalgh J. F. D. , McHattie I. 
Published: September 2010

ABSTRACTChanges in body composition during lactation were measured in 12 Border Leicester × Scottish Blackface ewes by serial slaughter at 12, 41 and 111 days of lactation. Ewes suckled twin lambs and were given daily 1·6 kg dry matter of a complete diet containing 151 g crude protein and 10·2 MJ metabolizable energy/kg dry matter.Live weights of ewes averaged 60·2, 58·9 and 55·8 kg at 12, 41 and 111 days of lactation respectively. There were no significant changes in weights of stomach, small and large intestine and liver.The weight of body fat averaged 9·19, 2·28 and 1·19 kg at 12, 41 and 111 days respectively (P < 0·001) and weight of ash increased from 1·72 kg at 12 days to 2·30 kg at 111 days (P < 0·001). Water to protein ratios at the three stages of lactation were 2·94, 3·36 and 3·18 (P < 0·10). The energy value of weight loss varied from 68 to 17 MJ/kg, depending on the relative changes in total body water and fat. Live-weight change was therefore a poor indicator of change in body energy during early lactation.Body fat could be predicted from its combined relationships with live weight and total body water (residual s.d. ±0·70 kg), but when deuterium oxide space was used to estimate body water separate equations were necessary for early and later stages of lactation. This was apparently due to differences between stages of lactation in the time required for deuterium oxide to equilibrate with water in the reticulo-rumen.
Double-low rapeseed meal for pigs: ileal apparent digestibility of amino acids in diets containing various proportions of rapeseed meal, fish meal and soya-bean meal
Authors: Partridge I. G. , Low A. G. , Matte J. J. 
Published: September 2010

ABSTRACTIn order to determine the relative nutritional value of rapeseed meal (var. Tandem) in comparison with soya-bean meal and fish meal, seven barley-based diets were formulated to provide 13·1 MJ digestible energy and 8·8 g total lysine per kg. They contained soya-bean meal (S), rapeseed meal (R) or fish meal (F) alone, or equal proportions (on a total nitrogen basis) of soya and rapeseed, soya and fish meal, rapeseed and fish meal or soya, rapeseed and fish meal. The study involved 14 pigs growing from 40 to 90 kg, each fitted with a T cannula in the terminal ileum. Dietary treatments were applied during 7-day periods according to a 7 × 7 Latin-square design, replicated twice. The pigs were fed at 12-h intervals. Ileal digesta were collected during two 12-h periods from each pig after adaptation to each diet. Nutrient apparent digestibilities were measured using chromium III oxide as a marker; for diets S, R and F, respectively, values were: dry matter, 0·58, 0·51 and 0·66 (s.e. 0·014); N, 0·72, 0·67 and 0·73 (s.e. 0·011); lysine, 0·79, 0·72 and 0·83 (s.e. 0·010), with a similar relationship between diets for most other amino acids. In general, values for diets containing combinations of the protein supplements were intermediate between those for diets containing the respective single supplements. Following the main trial, seven pigs were given a semi-purified diet containing rapeseed meal as the only protein source; this gave amino acid digestibility values similar to or slightly higher than diet R. Diet R, which contained 375 g rapeseed meal per kg, presented no palatability problem. Rapeseed meal of the quality used in this trial could contribute a substantial proportion of the protein supplement for growing pigs. Its value should be enhanced by formulating diets according to the ileal digestibility of the limiting amino acids.
Influences of production circumstances on the economic revenue of cattle breeding programmes
Authors: Groen A. F. 
Published: September 2010

ABSTRACTThe economic values of cattle production traits differ with different production circumstances. This sensitivity implies that (1) production circumstances influence the revenue of breeding programmes, and (2) losses in revenue of breeding programmes occur when circumstances used in defining breeding goals are incorrect with regard to actual production circumstances at the moments of expression of genetic superiorities. In this study, these effects are quantified for a set of genotype and index traits, including milk production traits, food intake capacity and live weight. Twenty-four situations of production circumstances were studied, including alternative output limitations, milk production levels, roughage qualities and product (milk, beef) and production-factor (food) prices.Results indicate that type of output limitation is the most important factor in determining revenue. Also, incorrect prediction of type of limitation leads to highest losses in revenue found (proportionately 0·01 to 0·06 of revenue). Losses in revenue due to incorrect prediction of production circumstances seem too low to justify complete diversification of cattle breeding goals within a breeding organization, except for different types of output limitations.
The direct and maternal components of the response to divergent selection for yearling growth rate in angus cattle
Authors: Herd R. M. 
Published: September 2010

ABSTRACTA crossmothering experiment was conducted to measure the direct and the maternal components of the response to divergent selection for yearling growth rate in beef cattle. The animals were from three closed lines of Angus cattle. Two lines had been selected since 1974 for either high (high-line) or low (low-line) average daily gain from birth to yearling, and the third line was maintained as a randomly bred control-line. A total of 221 female calves born between 1984 and 1987 was used in the crossmothering experiment, and an additional 113 cows bearing calves in 1988 were used to obtain more records of milk production.On average, high-line calves born in 1984-87 were 45 kg heavier at weaning (200 days of age) than low-line calves and 65 kg heavier at yearling age, corresponding to a proportional divergence in daily weight gain of 0·29 and 0·32 respectively. The direct component of the response to selection was 0·82 (s.e. 0-05) of the divergence in body weight at weaning and 0·89 (s.e. 0·05) at yearling age. The maternal component was 0·18 (s.e. 0·06) and 0·11 (s.e. 0·04) for weaning and yearling weight respectively. Over the years 1984-88, high-line dams produced 1·15 times the milk of low-line dams and only 1·03 times that of control-line dams. There were small differences in the composition of milk sampled in 1984 which resulted in the milk of high-line dams having a higher content of metabolizable energy (ME) than that of control-line dams. The ME in the milk consumed by the calves from the three selection lines was sufficient to fuel similar proportions of their pre-weaning growth and indicated that the expression of the maternal component of the selection response may be via small differences in the quantity and quality of the milk produced by the dams. Expression of the direct component appeared to be at least partially via differences in appetite of the calves. These results, together with results for sheep, mice and rats, show that the direct component of the response to selection for growth is much larger than the maternal component.
Hormonal induction of twinning in farmed red deer (Cervus elaphus): comparative mortality and growth of twins and singles to weaning
Authors: Fennessy P. F. , Moore G. H. , Littlejohn R. P. 
Published: September 2010

ABSTRACTMultiple births were induced in 20 hinds subjected to a progesterone plus gonadotropin treatment to advance the breeding season by about 4 to 5 weeks. In total, over 2 years, 92 hinds were treated and run with melatonin-treated stags. Of the 59 hinds that calved to the induced oestrus, 39 produced single calves, 19 produced twins and one produced triplets. Birth weight, gestation length, perinatal mortality and growth rate to weaning at ca. 20 weeks of age were compared for singles and twins. There was a significant effect of birth type on birth weight with twins being proportionately 0·30 lighter than singles (6·27 and 8-94 kg; P < 0·001), with a significant interaction between the birth weight of a calf and the sex of its co-twin (P < 0·05); males born as co-twins to females were proportionately 0·18 heavier than their co-twin females (P < 0·06), while in contrast twin male sets were substantially lighter than twin female sets. Gestation lengths were similar for both singles and twins, with significant negative relationships between gestation length and birth weight for both singles and twins, with a 2-day decrease in gestation length for a 1-kg increase in mean birth weight. There was a strong quadratic relationship between perinatal survival and birth weight; the expected mortality rates at 5, 8 and 11 kg birth weight derived from the relationship were 0·39, 0·11 and 0·39 respectively, indicating reduced probability of survival at both low and high birth weights. The regression relationships between weaning weight or growth rate to weaning and birth weight indicate that at the same birth weight, twin-reared calves were about 5 kg lighter than singles at 20 weeks, while an extra 1 kg weight at birth was associated with an extra 2 kg weight at 20 weeks.
Resumption of post-partum oestrous behaviour and associated plasma progesterone profiles in Menz ewes
Authors: Mukasa-Mugerwa E. , Ezaz Zere 
Published: September 2010

ABSTRACTFifty Ethiopian Menz ewes maintained on pasture grazing with uncontrolled mating showed ovarian cyclicity at all times of the year. Conception rates to first, second and third service were 78, 18 and 4%, respectively. Mean post-partum anoestrous interval was 76·1 (s.e. 4·6) days. Two-thirds of ewes conceived before lamb weaning at 90 days and had 8 month lambing intervals. Twice weekly progesterone determinations showed that 67% of ewes exhibited a silent ovulation 66·4 (s.e. 10·5) days post partum, 12% of oestrous cycles were longer than 20 days and 8% of heats were false or anovulatory. It was concluded that Menz ewes have the natural potential for three lambings in 2 years, under adequate nutrition. Their better management and genetic improvement should further reduce current lambing intervals and increase annual reproductive rates.
Influence of season on testicle size and libido in male goats from the Mediterranean area
Authors: Roca J. , Martinez E. , Vazquez J. M. , Ruiz S. , Coy P. 
Published: September 2010

ABSTRACTIn the Mediterranean environment and subtropical microclimate of the south-east Iberian Peninsula (37° 59' N), testicle size and sexual behaviour of male goats were studied and the influence of season (day length, air temperature and relative humidity) on these factors examined.Nine, 13-month-old Murciano-Granadina male goats weighing 47 to 53 kg were used. The experiment began during the month of January and extended for a complete year. Every 2 weeks, anterior-posterior maximum testis diameter was measured. They were tested twice a week for levels of sexual behaviour using ovariectomized goats and libido was evaluated as reaction time to mating.The annual mean testis diameter was 5·06 (s.e. 0·02) cm, varying significantly with season of the year. The lowest values were measured during winter 4·89 (s.e. 0·03) cm. These increased (P <0·01) in spring (5·16 (s.e. 0·01) cm) and summer (5·19 (s.e. 0·02) cm), but decreased again (P <0·01) in the autumn (5·04 (s.e. 0·02) cm). The annual mean reaction time was 197 (s.e. 12) s, but was longest (P <0·01) in spring (318 (s.e. 30) s), and shortest during summer (144 (s.e. 16) s) and autumn (132 (s.e. 17) s). The testicle diameter measurement was correlated with day length (r = 0·41; P <0·01) and air temperature (r = 0·45; P<0·01), while the reaction time showed no relationship with climatic measurements.It was concluded that day length is not the only factor responsible for seasonal variation in testis size of Murciano-Granadina male goats and that, in their natural habitat, libido is unlikely to be a limiting factor in the breeding programme.
A comparison of phase feeding and choice feeding as methods of meeting the amino acid requirements of growing pigs
Authors: Bradford M. M. V. , Gous R. M. 
Published: September 2010

ABSTRACTTwo experiments are reported in which a comparison was made of phase feeding and choice feeding as methods of meeting the changing amino acid requirements of growing pigs. In the first experiment, three feeding strategies were used: a system in which a single food (165 g protein per kg food) was offered throughout the growth period; a phase-feeding system, using five different treatments; and three choice-feeding treatments, in which the two diets offered differed only in their protein concentrations. The second experiment consisted of six treatments, three of which constituted a single feeding system, being a high, a medium, (the control) and a low protein food (240, 165 and 100 g protein per kg); there were two phase-feeding treatments, of three and five phases; and one treatment in which a choice was offered of the high and the low protein foods. In both experiments, group data were collected on Landrace × Large White pigs, sexes separate, during the growing period (30 to 90 kg). All pigs were weighed weekly, as was the amount of food consumed in each pen of 10 animals. Phase feeding improved food conversion efficiency (+4·4 g/kg) and caused a decline in both food intake (−45·3 g) and P2 backfat thickness (−0·4 mm) with each increment in the number of phases used. Results of the choice feeding treatments were not statistically significantly different from either the control or the phase feeding treatments. The intake of dietary protein was higher in the choice treatments than in the control (420 v. 370 g in experiment 1 and 345 v. 334 g in experiment 2). Where the two foods on offer differed only in protein content, pigs reduced the proportion of high protein food in the combination chosen by 0037 and 0·059 per week in the two experiments respectively, these linear trends being statistically highly significant. They were less successful in differentiating between the high protein food and maize, the proportion of high protein food chosen decreasing at a statistically significant rate of 0018 per week, but where the maize had not been supplemented with vitamins and minerals there was no significant trend in the way in which the pigs selected their diet, demonstrating the importance of the correct design of the two foods on offer in a choice-feeding programme.
The effect of semen collection frequency and food intake on semen production in breeding boars
Authors: Kemp B. , Barker G. C. M. , Hartog L. A. den , Verstegen M. W. A. 
Published: September 2010

ABSTRACTAn experiment was conducted to study the effect of feeding level and semen collection frequency on semen quantity and quality of 62 Yorkshire boars at two artificial insemination centres during 10 successive periods of 2 weeks. The experiment had a 2 × 2 factorial design with two feeding levels (2·75 and 3·5 kg/day) and two semen collection frequencies (three and five times in 2 weeks).In the first 2-week period boars on the high frequency semen collection scheme produced 94 × 109 sperm cells more than boars on the low scheme. In periods 2 to 10 the mean difference was only 18 × 109 sperm cells. Boars on the high feeding level produced 32 × 109 sperm cells more per 2-week period than the boars on the low feeding level (P < 0·05). Boars at the high collection frequency and the high feeding level tended to produce a higher number of sperm cells during periods 2 to 10 than the boars on the high semen collection frequency and the low feeding level (P > 0·05). No effects of food intake or semen collection frequency on semen quality were found.