bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of energy intake on protein and energy metabolism of boars of high genetic potential for lean growth
Authors: Rao D. S. , McCracken K. J. 
Published: September 2010

ABSTRACTTwo experiments were conducted each using one batch of six Landrace littermate, entire male, pedigree pigs in a Latin-square change-over study of the effects of energy intake on nitrogen and energy metabolism over the range 33 to 88 kg live weight. One animal from each litter was slaughtered at 33 kg body weight to obtain initial body composition data. Five feeding levels (80, 100, 120, 140 and 160g/kg M0·63) were used during five consecutive metabolism trials each of 11-days duration, excreta being collected during the last 7 days. The pigs were housed in individual metabolism cages and the diets were offered in liquid form (approx. 300 g dry matter (DM) per kg) twice daily at 09.00 and 16.00 h. Heat production was measured for 1 day during each balance period in an open-circuit respiration chamber. The average daily gain, nitrogen retention, heat production and energy retention increased linearly (P < 0·001) with increasing metabolizable energy (ME) intake. The relationship between energy intake and protein deposition was linear up to levels above the normal ad libitum consumption of energy. Protein deposition potential of these high genetic potential pigs was at least 200 g/day, and tended to be constant between 35 and 85 kg live weight. From the combined results of experiments 1 and 2, the energy requirement for maintenance was 0·982 MJ ME per kg M0·63 per day and the decrease in protein deposition was approximately 6 g/MJ reduction in ME within the range of practical energy intakes.
The effect of three concentrate input levels on the performance of dairy cows calving during mid-winter
Authors: Gordon F. J. 
Published: September 2010

SUMMARYA randomized block experiment was conducted using 27 British Friesian cows to assess the effects of three levels of concentrate input (589 (H), 456 (M) and 316 (L)±19·2 kg/cow) on performance. The animals, mean calving date of 6 January, were blocked according to calving date and allocated at random to treatments. All concentrates were given during the post-partum indoor feeding period (mean of 86 days) in addition to accessad libitumto grass silage. All animals received equal concentrate inputs/kg milk produced for 29 days after calving, following which the concentrate inputs were reduced, the reduction depending upon treatment. The milk outputs during the treatment period were 2147, 2075 and 1850 ± 75·8 kg and live weights at the end of the period were 504·1, 500·0 and 468·8 ± 4·96 kg for the H, M and L levels of concentrate supplementation respectively. Six animals per treatment were rotationally grazed at pasture at a stocking rate of 6·0 cows/ha for 11 weeks following the indoor feeding period. Performance at pasture was not affected significantly by previous treatment, with the milk outputs for the pasture period being 1647, 1673 and 1738 ± 53·0 kg, for the H, M and L treatments respectively. The milk outputs during the total indoor feeding plus grazing period at 3887, 3852 and 3636 ± 103·5 kg for the H, M and L treatments respectively did not differ significantly. Milk composition data are also presented.
The thin sow—observations on digestive efficiency, nitrogen balance and carcass composition
Authors: MacPherson R. M. , Campbell Rosa M. , Smart R. I. 
Published: September 2010

SUMMARYMeasurements were made of apparent digestibility of dry matter, nitrogen and lipid, nitrogen balance, pancreatic lipase activity and carcass composition in eight non-pregnant sows during three 10-day balance trials during which the feed intake was 1·1, 0·8 and 2·6 kg/day of a diet containing 14·69% crude protein and 3·0 Meal gross energy/kg DM.All the sows had similar breeding histories and had completed their fourth lactation. Four were in standard condition (mean body weight, 160 kg) and four in thin condition (mean body weight, 134 kg). All the animals lost weight and were in negative nitrogen balance while on the two lower levels of feed intake; the thin sows lost significantly more N than the standard animals (P< 0·05) and on the lowest level of feeding digestibility of DM by the thin sows was significantly less (P< 0·001).In both groups there was a rapid recovery in nitrogen retention and in body weight when the food intake was increased.
A note on the use of dexamethasone for inducement of parturition of Finn × Dorset ewes
Authors: Shevah Y. 
Published: September 2010

SUMMARYDexamethasone (16 mg) induced parturition in sheep when injected i n the dam on day 141 of gestation. The mean time of parturition was 49·0 ±2·18 hr after the injection, with 90% of the injected ewes lambed by the 143rd day of gestation compared with the 147th day in the control group. There was no ill effect on the ewe or the lamb born.
The performance and intake of weaned lambs grazing S24 perennial ryegrass, with and without supplementation
Authors: Newton J. E. , Young N. E. 
Published: September 2010

SUMMARYTwo forms of supplement, barley or dried grass pellets (G) were given to weaned lambs, set-stocked at pasture, at three stocking rates (43·5, 60 and 87 per hectare). The supplements were given either from weaning or from the time growth rate fell below a target value. The supplements significantly increased the proportion of lambs reaching the target weight (35 kg) and G was significantly better than barley, but slightly more G was given. The substitution value of supplement for herbage was 0·48 ± 0·12 and there was no difference in this value between barley and G. The proportion of lambs reaching the target slaughter weight was not influenced by whether the supplement was offered at weaning or delayed until lamb growth declined below a target level. Increase in stocking rate depressed the herbage intake and growth rate of the unsupplemented control lambs.
A note on further studies on sodium salicylate as a growth stimulant for growing pigs receiving diets with or without copper sulphate
Authors: Barber R. S. , Braude R. , Mitchell K. G. 
Published: September 2010

SUMMARYResults are reported of an experiment with 60 pigs (12 pigs/treatment) covering the growing period between 22 and 87·5 kg live weight in which the growth-stimulating properties of sodium salicylate were examined either as a single additive or with copper sulphate. The pigs were individually fed a wet diet ‘to appetite’ and the quality of the carcasses was assessed at slaughter.No significant improvement in live-weight gain or feed: gain ratio was obtained when either 200 or 700 mg of sodium salicylate/kg was added to the diet. When 700 mg of salicylate was given together with 250 mg Cu/kg diet, the response in growth rate was significantly higher than that obtained from the addition of copper alone.There was no significant treatment effect on carcass quality as assessed by linear measurements, nor on the dry matter, nitrogen or ash contents of the gluteus medius muscle.
The effect of avoparcin and monensin on the performance of growing and finishing cattle offered grass silage-based diets
Authors: Unsworth E. F. , McCullough I. I. , McCullough T. A. , O'Neill D. G. , Steen R. W. J. , Titterington C. I. 
Published: September 2010

ABSTRACTThe effect on animal performance of the inclusion in the diet of avoparcin at one or more of the following levels 0, 150, 300 and 450 mg per head daily and 200 mg per head daily monensin was studied i n a series of four trials. Finishing cattle of 428 (s.e. 3·9) kg live weight were used in three trials and yearling heifers (218 (s.e. 4·9) kg live weight) in the fourth. All animals received grass silage ad libitum with 0·5 to 6·0 kg per head daily of a cereal-based supplement. Relative to the control diets with no additive, proportionate increases in live-weight gain of between 0·07 and 0·38 were obtained with the inclusion of avoparcin at 150 mg per head daily in the diet with a small depression in silage dry-matter intake. The effects at higher levels of inclusion of avoparcin and of monensin were more variable. Alteration in the proportion of propionate to acetate in the rumen fluid of the animals was observed only at the highest levels of additive inclusion. There was no effect of additive treatment on carcass weight or dressing proportion.
A note on the method of replicate blood sampling when assessing the mean concentration of insulin, prolactin and growth hormone in the plasma of heifers fed different diets at different frequencies
Authors: Little W. , Harrison R. D. , Williams Linda A. , Hart I. C. 
Published: September 2010

ABSTRACTTwo groups of six heifers of mean age 284 days and mean body weight 233 kg were offered respectively, a barley-beef (BB) diet and a diet based on dried grass and sugar beet pulp (DG) at a rate calculated to give a live-weight gain of 0·5 kg/day. Three heifers from each group were fed twice daily, and the remaining three were fed through an out-of-parlour concentrate dispenser, and, during the period of blood sampling, hourly. Following a period of adaptation, blood samples were taken hourly during 24 h and the plasma analysed for insulin, prolactin and growth hormone (GH). The experiment was repeated 28 days later using the same heifers offered the same diets except that the twice-daily fed heifers were fed hourly and vice versa.Comparing the heifers fed the BB diet and those fed the DG diet, insulin in plasma was higher (7·11 v. 3·54 mU/1, P < 0·001) and GH lower (2·48 v. 3·41 uxg/l, P < 0·05) in heifers fed the BB diet. There were no overall significant differences between the two diets for prolactin or between the two frequencies of feeding for all three hormones.The residual variation among and within heifers was used to estimate the standard error of a treatment mean for different numbers of hourly samples on different numbers of heifers. Little was to be gained by taking in a day more than eight hourly-samples for insulin and more than 12 hourlysamples for GH and prolactin. Precision was most improved by increasing the number of heifers sampled. Feeding the heifers more than twice daily did not improve precision significantly.
The voluntary intake of hay by sheep in relation to its degradability in the rumen as measured in nylon bags
Authors: DeB. Hovell F. D. , Nǵambi J. W. W. , Barber W. P. , Kyle D. J. 
Published: September 2010

ABSTRACTThe voluntary intake and digestibility of four hays were measured with eight sheep using two 4 × 4 Latin squares. Measurements were made during the last 8 days of each 3-week period. The degradation characteristics of the hays were measured by incubating samples (in nylon bags) for 12, 24, 48 or 72 h in the rumen of four sheep fitted with rumen cannulae and given a good hay. The exponential p = a + b(1 − e−α) where p = degradation loss, t = time, and a, b and c are constants, was fitted. The potential degradability (defined as a + b) of the dry matter (DM) of the four hays was 0·76, 0·66, 0·54 and 0·46 with corresponding voluntary intakes of 71, 62, 52 and 45 ± 2·9 g DM per kg M075 per day. The in vivo digestibilities were 0·61, 0·59, 0·46 and 0·45 (s.e. 0·013) respectively and corresponded to 23-, 25-, 31- and 67-h degradation. Voluntary intake was better related to potential degradability (and degradability at 12, 24, 48 and 72 h) than to in vivo digestibility. It is concluded that the degradation characteristics of forages may have useful application in predicting voluntary intakes, and that potential degradability could be used to define the rumen (jegradable nitrogen content necessary with any particular forage.
The effect of restricted energy and nutrient intake after mating on reproductive performance of multiparous sows
Authors: Dyck G. W. , Cole D. J. A. 
Published: September 2010

ABSTRACTNinety-six multiparous sows were allocated at random on the 1st day of mating at the post-weaning oestrus to three dietary treatments of: 1·84 kg control diet (C); 0·92 kg control diet plus 0·92 kg pelleted hay (R); or 1·84 kg pelleted hay per day (M) for the following 10-day period to determine if restriction of nutrient intake affected reproductive performance. Subsequent to the 10-day period of nutrient intake restriction, all sows were fed 1·84 kg control diet once daily. The treatments had no effect on pregnancy rate, number of piglets born, number born alive, number weaned, or on piglet weight at birth or at weaning. Sows on the M treatment from oestrus to day 10 lost more weight (8·6 kg) during the 10-day period of nutrient restriction than the sows on the R (3·4 kg) or. the C (0·7 kg) treatments. However, weight gain from oestrus to day 110 of gestation was similar for all three treatments (16·5, 17·8 and 17·1 kg, respectively). Thus, restriction of nutrient intake early in pregnancy is not a critical factor affecting litter size and weight at birth or weaning in the multiparous sow.
Selection indices to improve the efficiency of lean meat production in cattle
Authors: Simm G. , Smith C. , Prescott J. H. D. 
Published: September 2010

ABSTRACTSelection indices to improve the efficiency of lean meat production in cattle were derived with an aggregate breeding value which comprised growth rate, food conversion efficiency, killing-out proportion and carcass lean proportion. Index measurements were growth rate, food conversion efficiency and ultrasonic fat area. Relative economic values of traits in the aggregate breeding value were calculated for an 18/20-month beef system, assuming a fixed national output of lean meat. Literature estimates of phenotypic and genetic parameters were used. Two indices were derived, one with a complete restriction on genetic changes in birth weight, and the other without restriction. Correlations between the index and the aggregate breeding value were 0·53 for the restricted index, and 0·57 for the unrestricted index. The maximum proportional reduction in expected economic response, due to complete restriction of birth weight was about 0·08. Selection on either index would actually lead to a slight decrease in carcass lean proportion, but this was less than the decrease expected from selection solely on growth rate. Correlations between the indices and the aggregate breeding value (measuring the accuracy of selection) fell by only about 0·01 when ultrasonic measurements were omitted from the index, but fell by about 0·09 when food conversion efficiency was omitted. Sensitivity of the indices to changes in parameters was also examined. With proportional changes of ±0·5 in individual economic weights, or absolute changes of ±0·2 in genetic correlations or −0·2 in heritabilities, the efficiency of selection ranged from 0·93 to 1·00.
The effects of a combined androgenic-oestrogenic anabolic agent in steers and bulls 2. Muscle weight distribution, partition of body fat and carcass value
Authors: Wood J. D. , Fisher A. V. , Whelehan O. P. 
Published: September 2010

ABSTRACTTwenty-one pairs of male cattle twins, 10 of which were monozygotic, were used in a study of the effects of a combined implant of trenbolone acetate (140 mg) and oestradiol-17β (20 mg) on muscle distribution, fat partition and carcass value. There were three comparisons within pairs: (1) between bulls and steers (no implants); (2) between bulls and implanted steers; and (3) between bulls and implanted bulls.Implants were given twice, at 44 to 73 and 300 days of age, and animals were slaughtered at 400 days following ad libitum consumption of a complete pelleted diet. The effects of castration and/or implantation on muscle distribution, fat partition and carcass value were assessed by comparison with the untreated (control) bull values within each group and expressed as a ratio (treatedxontrol). These ratios were then compared between groups.Implantation of steers increased slightly the weight of muscles in the neck which in a preliminary study had been shown to be particularly heavy in mature bulls compared with steers. Implantation therefore produced a more bull-like muscle distribution in steers and the effect in bulls was to increase the weight of these muscles even further. In steers and bulls the partition of body fat was not affected by implantation. Both implanted steers and bulls were fatter than their respective control bulls and their fat partition was appropriate to this (higher subcutaneous to intermuscular fat ratio).Differences in carcass value between the groups, as evidenced by a retail cutting method applied to the right side of the carcass, reflected these differences in muscle distribution and fat partition. Thus, implantation of steers was judged to be economically advantageous despite the marginal reduction in value brought about by enlarged forequarter musculature. Implanted bull carcasses were less valuable than their respective controls mainly because they were fatter and required more trimming.
Milk production from silage 4. The effect of the composition of the supplement
Authors: Thomas C. , Aston K. , Daley S. R. , Bass Jacqueline 
Published: September 2010

ABSTRACTPrimary growths of perennial ryegrass (Lolium perenne) were cut on 22 May and 12 June and wilted for 24 h prior to ensiling. A 40: 60 mixture of the two silages was offered ad libitum with two pelleted supplements. Supplement Ba was a mixture of (dry matter (DM) basis) 932 g rolled barley and 68 g fish meal per kg. Supplement SBP/FF consisted of 555 g unmolassed beet pulp, 314 g extracted rice bran, 56 g fat prills and 75 g soya-bean meal per kg. The factorial combination of the two supplements (Ba and SBP/FF) given at two levels, 6 kg DM (L) or 12 kg DM (H), provided the four treatments imposed over weeks 3 to 10 of lactation on 40 British Friesian cows. During weeks 12 to 20 of lactation (post-experiment period) the cows were given an equal mixture of the two concentrates at 9 kg DM per day.Supplement Ba contained less ash (31 v. 94 g/kg), acid-detergent fibre (68 v. 218 g/kg) and fat (29 v. 77 g/kg) but more starch (558 v. 89 g/kg) and digestible organic matter in the dry matter in vitro (DOMD) (781 v. 627 g/kg) than SBP/FF. The concentration of total nitrogen (N) was similar at 25·6 g/kg. Silage had a DOMD of 643 g/kg, a pH of 3·8 and proportionately 0·82 of fermentation acids as lactic acid.Apparent digestibility of gross energy was higher for Ba diets (0·748) than for SBP/FF (0·704). Cows given SBP/FF ate 0·9 kg more silage DM than those given Ba (P < 0·01) but there was no difference in digestible energy intake or in substitution rate (−0·37 kg silage DM per kg additional supplement DM). Increasing the amount of supplement increased milk yield by 3·9 kg/day (P < 0·001). Cows given SBP/FF yielded on average 1·6 kg more milk than those given Ba (P < 0·05). However, this increased output consisted almost entirely of lactose and water as a result of a high concentration of fat in the milk of cows given Ba at the low level (46·3 g/kg). Further, the concentration of protein was less with SBP/FF (28·0 g/kg) than with Ba (29·2 g/kg).The effects of SBP/FF in early lactation were translated into a positive residual effect in mid lactation equivalent to the immediate effect. In contrast, raising yield by increasing the amount of supplement did not result in increased output subsequently. The results show that a supplement of fibre and fat despite having a lower digestibility than barley can produce more milk but a similar yield of fat and protein provided silage is offered ad libitum.
Diets with chemically treated straw for beef steers: effects of rapidly fermentable carbohydrate on food utilization, growth and bacterial cellulolysis
Authors: Williams P. E. V. , Stewart C. S. , Macdearmid A. , Brewer A. 
Published: September 2010

ABSTRACTThe effects of level of supplemental carbohydrate from turnips and level of rumen degradable nitrogen on bacterial cellulolysis, food intake, live-weight gain and diet digestibility were examined with 36 300-kg Friesian steers allocated, in a randomized-block design, to one of six dietary treatments: (i) sodium hydroxide treated straw plus a supplement of urea (30 g urea per kg straw dry matter (DM)) (uO); (ii) uOplus turnips (23·5 g DM per kg M0·75); (Hi) uOplus a high level of turnips (47 g DM per kg M0·75); (iv) (v) and (vi), the same three diets, but with additional urea (60 g urea per kg straw DM). In two separate experiments each lasting for 56 days, the turnip allowance was given in either two feeds, or one feed per day and the straw was given to appetite. Rumen fluid was obtained by stomach tube from all steers before feeding (07·30 h) and after feeding (11.00 h) on days 10 and 24 of each experiment.Weight gains for all groups given straw plus turnips were high (> 0·90 kg/day). Increasing the quantity of turnips gave significantly increased DM intakes and weight gains but then turnips substituted for straw, and the proportion of straw consumed decreased from 0·8 to 0·6 of the dietary DM (P< 0·01) There were no significant interactions between frequency of feeding of turnips and level of urea on the variables food intake and weight gain. Fibre digestibility was not depressed by the addition of turnips to the diet. Rumen fluid pH decreased after the steers ate turnips but tended to remain above 6·7. There were no large changes in the total number of viable cellulolytic bacteria as a result of either addition of urea or turnips to the diet; counts remained in the order of 107 per ml. Steers consumed large quantities of sodium hydroxide treated straw; turnips were therefore only a small proportion of the overall DM intake with relatively little effect on bacterial cellulolysis.
Inter-age correlations of food conversion efficiency with body weight, growth rate and food intake within and between British breeds of cattle
Authors: Thiessen R. B. , Taylor St C. S. 
Published: September 2010

ABSTRACTIn a multibreed experiment 306 females from 25 British breeds of cattle were given a standard pelleted diet ad libitum. Correlations of food conversion efficiency (FCE) with body weight, weight gain, and food intake were studied over 12-week and longer periods from 12 to 72 weeks of age. Inter-age correlations of FCE with itself and the other traits were also studied over age intervals separated by 12, 24, 36 and 48 weeks. The between-breed correlations were genetic while the within-breed correlations were phenotypic.Between breeds, FCE measured over the full age range from 12 to 72 weeks appeared to be very highly correlated with FCE measured over the 12-week period between 24 and 36 weeks of age. Correlations of 12 to 72 week FCE with traits not requiring measurement of food intake were much lower, being at most 0·77 for weight gain, 0·73 for weight gain per unit body weight and 0·57 for body weight. The pattern of correlations implied that over constant age ranges the larger faster-growing breeds with high intakes tended to be more efficient; however, these correlations were generated primarily at early ages between 12 and 36 weeks and FCE at later ages could not be predicted from other traits measured at earlier ages. Nevertheless, between-breed selection to improve FCE by indirect selection on body weight and weight gain could be effective but there would appear to be no advantage in waiting beyond 1 year of age.Within breeds, correlations of 12 to 72 week FCE with FCE measured over 12-week periods increased with age from 0·24 to 0·61. Correlations of FCE with weight gain in the same 12-week periods were quite high (0·49 to 0·89) and those with weight gain per unit weight were invaribly higher (0·68 to 0·90). However, as a predictor of FCE in any subsequent period, weight gain per unit body weight was poor and weight gain of no value whatsoever. There was no strong association of FCE with body weight.