bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of diet composition, dry-matter intake, milk production and energy balance on time of post-partum ovulation and fertility in dairy cows
Authors: Lucy M. C. , Staples C. R. , Thatcher W. W. , Erickson P. S. , Cleale R. M. , Firkins J. L. , Clark J. H. , Murphy M. R. , Brodie B. O. 
Published: September 2010

AbstractLactating Holstein-Friesian cows from two calving groups (no. = 90) were studied during the early post-partum period to determine the effect of dry-matter intake (DM1), 40 g/kg fat-corrected milk (FCM) production, energy balance (EB), parity, and food additives (calcium salts of long-chain fatty acids [CaLCFA] and niacin) on the recrudescence of ovarian function and establishment of pregnancy. Cows that ovulated early during the post-partum period (15 to 21 days after calving) consumed more food and tended to produce more FCM compared with cows ovulating later (22 to 42 days or after 42 days). Primiparous cows had lower EB and tended to have longer intervals to first ovulation compared with multiparous cows but the average interval to pregnancy was similar for primiparous and multiparous cows. Feeding CaLCFA tended to extend the interval to first service and decreased pregnancy rate. Production characteristics (including DMI and FCM production) seem to determine interval from calving to first ovulation as well as interval from calving to pregnancy (days open). Fertility was affected negatively by feeding CaLCFA.
Correlated responses in slaughter and carcass traits of crossbred progeny to selection for carcass lean content in sheep
Authors: Cameron N. D. 
Published: September 2010

AbstractCorrelated responses in slaughter and carcass traits to divergent selection for high or low carcass lean content in Texel-Oxford sheep were measured in the crossbred progeny of 23 rams. Rams were selected using the selection index: -0·995 FATD + 0·206 WT20, where FATD and WT20 are the ultrasonic backfat depth and live weight at 20 weeks of age, with both traits standardized to have zero mean and unit phenotypic variance. A total of 329 crossbred lambs were slaughtered at 16 weeks of age and 250 lambs were slaughtered at fixed weight, 38 to 40 kg for castrated males and 36 to 38 kg for ewe lambs. Progeny from high-line rams grew faster, as indicated by the heavier slaughter weight of lambs slaughtered at fixed age (04 (s.e.d. 0·5) kg) and the lower age at slaughter for lambs slaughtered at fixed weight (-5 (s.e.d. 3) days). Subcutaneous and internal fat scores and the Meat and Livestock Commission carcass appraisal and conformation scores were all lower in the high line than in the low line and the magnitude of the selection line differences for lambs slaughtered at fixed weight was essentially double that of lambs slaughtered at fixed age (0·8 v. 0·5 score units).Shoulder joints of 254 lambs, slaughtered at fixed age, were dissected and half carcasses were dissected on 66 of the lambs. Carcass and shoulder joint information was combined with double-sampling methodology, using multiple regression equations to predict carcass composition. For each tissue type, viz. lean, subcutaneous fat, internal fat and bone, the correlations between carcass content and shoulder joint content were at least 0·90 and the proportions of variation in carcass tissue content accounted for by the prediction equations were also at least 0·90. Progeny of high-line rams had higher carcass lean weight, (402 (s.e.d. 140) g) than progeny from the low line, with no difference in carcass fat weight, such that carcass lean content was higher, (10 (s.e.d. 5) g/kg), and carcass fat content was lower, (-10 (s.e.d. 7) g/kg). Based on the slaughter and carcass traits of these crossbred progeny, divergent selection for high and low carcass lean content has established lines of animals with different rates of lean growth but similar rates offat deposition.
Changes in body components of autumn-calving Holstein-Friesian cows over the first 29 weeks of lactation
Authors: Gibb M. J. , Ivings W. E. , Dhanoa M. S. , Sutton J. D. 
Published: September 2010

AbstractChanges in body composition of 54, second to fourth parity, autumn-calving Holstein-Friesian dairy cows offered grass silage ad libitum and 3(L), 6(M) or 9(H) kg concentrate dry matter per day were measured by serial slaughter at 0, 2, 5, 8, 11, 14, 19, 24 and 29 weeks post partum.Concentrate level had a significant effect on the fresh weights of many of the body fractions with the differences generally being greater between L and M than between M and H. Increasing concentrate level generally reduced the extent of weight loss of body fractions in early lactation and enhanced subsequent repletion. Empty body weight decreased to week 8 and then increased steadily over the remaining 21 weeks, but within this pattern different organs were concomitantly increasing and decreasing. Carcass weight and the weights of the internal fat depots showed a decline over the first 8 weeks and a subsequent increase, udder weight declined throughout, weights of various sections of the digestive tract showed an initial increase then remained steady, whilst liver weight increased throughout.In week 0 the carcass accounted for proportionately 0-61 of the total energy in the body (6278 MJ), of which fat and crude protein (CP) comprised proportionately 0·67 and 0·33, respectively. In early lactation mobilization of fat and CP in the carcass was reduced with increasing level of concentrate. In the non-carcass fraction increasing concentrate level led to a higher weight of CP in the metabolically active organs such as the digestive tract and udder but had little effect on the weight of fat. Nevertheless, there was generally a positive effect of concentrate level on energy content. Total weights of fat, CP and water in the body declined to week 8 then increased over the following 21 weeks. Although weight of CP in the liver increased throughout lactation and weight of fat was elevated in weeks 0 and 2, the energy content of the liver remained fairly constant.Estimates of the change in net energy (NE) associated with live-weight loss and with live-weight gain showed a slight though non-significant difference between the two, despite evidence of a higher concentration of fat associated with gain than with loss, and CP concentration being the same in both cases. The mean value was 19·3 MJ/kg live-weight change.
An assessment of the biological and economic efficiency in conversion of milk to growth in N'Dama calves
Authors: Agyemang K. , Clifford D. , Little D. A. 
Published: September 2010

AbstractTwo groups of eight N'Dama calves were fed different quantities of milk from birth to 10 months of age to compare efficiencies of converting milk to live-weight gain, and to assess the economic efficiencies of the two feeding regimes. Group 1 received an average of 347 (s.e. 2·4) kg per calf, with a daily and seasonal pattern of feeding designed to simulate a village production system where calves have access to only part of the milk produced by their dams, the rest being extracted for human consumption. Group 2 received an average of 617 (s.e. 5·1) kg per calf, and simulated situations where no milk is extracted such as in a ranch or station-type of operation.During the first 6 months, when growth was certainly mediated only by milk, and live-weight gains were consistently positive at 151 and 262 g/day in groups 1 and 2 respectively, the biological conversion of milk to live weight did not differ between groups (8·7 v. 8·8 kg milk per kg live-weight gain). When the two groups were compared over the same weight range to remove possible effects of variable maintenance requirements, the conversion efficiencies again did not differ significantly. Over the whole 10-month period the biological conversion factors were slightly less favourable but still not different between groups (9·5 v. 9·4 kg/kg). When monetary values of milk and live weight at farmgate prices were applied to quantities of milk consumed and calf live-weight increases, the cost efficiency of group 1 was superior to that of group 2.Based on these findings and results from other on-farm experiments in The Gambia, it was concluded that the current practice of partial milk extraction as occurs in the village production system is a logical approach for profit maximization.
Lamb mortality in Scottish hill flocks
Authors: Gunn R. G. , Robinson J. F. 
Published: September 2010

SUMMARY1. Records on lamb mortality from birth to marking at approximately 6 weeks are summarised for four seasons in one Cheviot and three Scottish Blackface flocks and discussed in relation to the breed, environmental and management differences existing on the three farms of Sourhope, Roxburghshire; Lephinmore, Argyllshire and Glensaugh, Kincardineshire.2. The mortality rates in single-born lambs from three-year-old and older ewes, following hill lambings, were 12% and 6% respectively in the Cheviot and Blackface flocks at Sourhope and 14% in the Blackface flock at Lephinmore. In the Blackface flock at Glensaugh, the mortality rate following regular pre-lambing feeding and lambing on cultivated pastures was 5%.3. There was considerably heavier mortality in twin-born lambs, and in single-born lambs from two-year-old ewes, notably as a result of increased loss subsequent to birth.4. Among single-born lambs, more males were lost than females, the difference being between 1% and 8% according to the farm and being largely due to a greater frequency of difficult births among males.5. Lambs with birth weights markedly heavier or lighter than average had a higher percentage of mortality.6. An abnormal incidence of loss from difficult birth in a Cheviot sub-flock in 1957 is described.
A comparison of cubes and meal for growing and fattening pigs
Authors: Laird R. , Robertson J. B. 
Published: September 2010

SUMMARY1. Thirty-six Large White fattening pigs, eight to nine weeks old at the beginning of the trial, were used to study the effects of cubing pig rations.2. There were three treatments, meal, cubes and cubes reground to meal.3. Pigs fed on cubes had significantly higher growth rates (by 0·09 ± 0·03 lb. per day or 7·1%) than those fed on meal.4. Food conversion was significantly lower, by 0·18 ± 0·05 lb. feed per pound gain, for cube-fed pigs. The saving in feed was 5·1% for the complete fattening period, this difference being statistically significant (P < 0·001).5. No significant differences between treatments were recorded for any of the carcass measurements.6. Meal-fed pigs had significantly lower dressing-out percentages than those fed cubes.7. There were no significant differences in performance between pigs fed on cubes and ground cubes.
Further studies on the water requirements of the growing pig
Authors: Barber R. S. , Braude R. , Mitchell K. G. 
Published: September 2010

SUMMARY1. Results of an experiment involving 48 individually-fed pigs, covering the growing period between about 40 and 208 lb. live-weight, indicated that reduction in the amount of water allowed per lb. of meal from 3 lb. to 2 lb. or 1½ lb. had no significant effects on either the performance or the carcass quality of the pigs.2. Provision of an unrestricted supply of water, in addition to the allowance of 1½ lb. added to each lb. of meal, resulted in a significant improvement in the rate of weight gain which was caused almost entirely by an increase in daily meal consumption by these pigs.3. Under the conditions of the experiment, the provision of water ad lib. was not accompanied by any adverse effects on carcass quality, although conditions under which it might do so are discussed.4. The data on water consumption of the pigs indicated that the observed effects on performance of providing water ad lib. did not arise as a result of a deficiency in the total water intake of the pigs given a restricted supply. The possibility is discussed that the length of time that water was available to the animals might be of importance.
A genotype-environment interaction experiment with bacon pigs
Authors: King J. W. B. 
Published: September 2010

SUMMARYA genotype-environment interaction experiment was carried out on a total of 140 pigs. Three genotypes, produced by mating an inbred boar of each of the Large White, Landrace and Wessex Saddleback breeds to Large White sows, were fattened on conventional rations and on a high growth ration with 10% fat and growth promoting additives.The high growth ration increased growth rate by 34% and improved food conversion ratio by 26% and gave a higher dressing-out percentage, but produced shorter and fatter carcasses. No significant genotype-environment interactions were found for growth rate or food conversion. A significant interaction was found for streak thickness but not for other carcass measurements.
Intensive beef production 4. The effect on nitrogen retention of all-concentrate diets containing different levels of fish meal
Authors: Bowers H. B. , Preston T. R. , McDonald I. , MacLeod N. A. , Philip Euphemia B. 
Published: September 2010

SUMMARY1. All-concentrate diets given ad libitum and containing different levels of fish meal, and varying in crude protein content from 16 to 22% in dry matter were given to eight Friesian steers at 150 kg. and at 240 kg. live-weight.2. At a mean live-weight of 150 kg., the retention of nitrogen increased significantly to a maximum of 41.5 g. per day on the diet having 22% crude protein in dry matter. At 240 kg. live-weight, the maximum retention of 37 g. per day was achieved at 20% crude protein in dry matter.3. Faecal nitrogen excretion per unit of metabolic body weight was approximately constant at all protein levels and at both live-weights.4. Urinary nitrogen excretion per unit of metabolic body weight increased with increasing crude protein level in the diet and for any crude protein level was higher at 240 kg. than at 150 kg. live-weight.
The interaction between dietary lipids and fibre in the sheep 2. Digestibility studies
Authors: Devendra C. , Lewis D. 
Published: September 2010

SUMMARYDigestibility studies were carried out to establish the inter-relationship between crude fibre and total lipid digestibility in the presence of added calcium or non-ionic detergents. Three levels of calcium, corresponding to daily intakes of 2·3, 4·8 and 22·9 g per sheep, were used in a predominantly ground barley diet (65 to 73%) to which was added 8% beef tallow or maize oil. Two non-ionic detergents were used at 0·1% of the diet: nonyl phenol ethylene oxide and fatty alcohol combined with 3 molecules of ethylene oxide.With a daily intake of 2·3 or 4·8 g calcium per sheep, supplementation with fat resulted in a reduced fibre digestibility. When the intake was increased to 22·9 g, there was a significant improvement (P<0·05) only for the maize-oil-supplemented diet. Increasing calcium intake, associated with increased calcium digestibility, significantly (P<0·05) depressed total lipid digestibility. Intake of 4·8 g calcium per day was associated with the highest calcium digestibility of 33% digestibility units and the total lipid digestibility of 94%. Maize oil was better digested than beef tallow with the lower level of calcium; the position was reversed with the higher level of calcium supplementation. No advantages were found for crude fibre and total lipid digestibility when detergents were added.A possible mechanism by which the physical wetting of dietary lipids causes decreased digestibility of the fibre component is discussed.
A note on the effect of once, twice or three times a day feeding with concentrate on the efficiency of utilization of a diet given to beef cattle
Authors: Renton A. R. , Forbes T. J. 
Published: September 2010

SUMMARYAn experiment was carried out in which equal amounts of concentrate were given to beef cattle once, twice or three times per day, with a basal hay diet. There were no significant differences between treatments in food and water intake, digestibility coefficients, nitrogen balance data or live-weight gain.
The effect of supplementary protein on the performance of dairy cows offered grass silage ad libitum
Authors: Laird R. , Leggate A. T. , Castle M. E. 
Published: September 2010

ABSTRACTSixty-four lactating dairy cows (Ayrshire, British Friesian and Shorthorn × Ayrshire) were offered grass silage with a dry-matter content of 258 g/kg, and containing 75 g/kg digestible crude protein and 64·6% digestible organic matter in the dry matter for an average period of 16·7 weeks. The control and supplemented groups, each of 32 cows, received concentrates containing on a fresh basis 14% and 18% crude protein respectively which were offered at the rate of 0·4 kg/kg milk for yields above 2·3 kg/day. The mean daily yields of milk were 17·4 and 19·5 kg/cow, silage dry-matter intake 8·16 and 9·00 kg/cow per day and concentrate dry-matter intake 5·36 and 5·94 kg/cow per day on the control and supplemented treatments respectively and these differences were highly significant. The treatments had no significant effects on milk yield and composition in the post-experimental grazing period.
Production in mature corriedale ewes first mated at 7 to 11 or 18 months of age
Authors: Ponzoni R. W. , Azzarini M. , Walker S. K. 
Published: September 2010

ABSTRACTProduction in 210 mature Corriedale ewes first mated between 7 and 11 or at 18 months of age was studied at Paysandu, Uruguay. Ewes were classified into one of the following five classes according to their oestrous and lambing performance in 1968: (1) reared a lamb; (2) lambed but lamb died; (3) mated but did not lamb; (4) oestrus detected by vasectomized ram, true mating deferred for 12 months; and (4) no oestrus, mating deferred for 12 months. Records on flock performance and mortality were kept from all ewes from 1969 to 1973, when the dental status of all ewes present was assessed.There were no significant differences between classes in number of ewes lambing per ewe exposed to the ram, number of lambs born per ewe exposed to the ram, number of lambs weaned per ewe exposed to the ram, weight of lamb weaned per ewe exposed to the ram, and pre-mating body weight.Greasy fleece weight varied significantly (P < 0·01) with class of ewe. The least squares means for ewe classes 1 to 5 were 3·93, 3·99, 4·06,4·12 and 3·92 kg respectively. Class 4 ewes differed significantly (P < 0·01) from class 1 ewes and from class, 3 and 5 ewes (P < 0·05). Class 3 ewes differed significantly (P < 0·05) from class 1 ewes. Other differences were not significant.Ewe mortality between 1969 and 1973 was independent of class of ewe. The dental status of ewes appeared to vary with class of ewe. Early mating of Corriedale ewes apparently had no adverse effects on mature reproductive performance, but somewhat reduced wool production. If mating is to take place for the first time at 18 months of age, ewes that have shown oestrus previously are likely to exhibit greater overall productivity (wool plus lambs).
A seriatim study, using ultrasonic measurements, of fat depth and m. longissimus area in Hereford bulls, steers and heifers under grazing conditions
Authors: Truscott T. G. , Tulloh N. M. , Whitfield D. E. 
Published: September 2010

AbastractMeasurements of live weight and of ultrasonic (Scanogram) fat depth and m. longissimus cross-sectional area at the 12th/13th rib were taken at 4— to 6-week intervals from 10 to 35 months of age (23 occasions) on 15 Hereford males (bulls), 15 castrate males (steers) and 15 females (heifers) managed under grazing conditions.Mean rates of live-weight change throughout the measurement period (0·51, 0·47 and 0·39 kg/day for bulls, steers and heifers, respectively) were significantly different. When compared at the same ages, fat depth was similar in the steers and heifers, beginning at about 3 mm and increasing to 11 mm. Fat depth changed little in the bulls, beginning at 1·7 mm and increasing to 3 mm. At the same age, bulls had larger m. longissimus cross-sectional areas than steers and steers had larger muscle cross-sectional areas than heifers.Absolute variation within sex groups increased throughout the experiment in live weight and fat depth, but not in m. longissimus crosssectional area. Simple correlation coefficients, pooled within sex groups, of relationships between the same measurements at various measuring occasions, indicated that measurements of fat depth and of muscle cross-sectional area at 10 to 12 months of age are poor indicators of these measurements at periods of 6 months or more later in life.When compared at the same live weights, heifers had the greatest and bulls had the smallest fat depth and, within animals, fat depth was closely related to live weight. At any live weight, m. longissimus cross-sectional area was less in heifers than in steers and bulls, which were not significantly different from each other in this trait. Equations relating fat depth and muscle area to live weight are presented and, under the conditions of this study, indicate that there is no basis for adjustment of fat depth for live weight in bulls subjected to contemporaneous selection.
Genetic and environmental influences on beef cattle production in Zambia 3. Carcass characteristics of purebred and reciprocally crossbred castrated males
Authors: Thorpe W. , Cruickshank D. K. R. , Thompson R. 
Published: September 2010

ABSTRACTCarcass characters for 365 male castrate cattle of the Africander, Angoni, Barotse and Boran breeds, and the reciprocal crossbreds of the latter three breeds, are reported. In each of the two year-of-birth groups, different slaughter-age/management regimes were used. For all carcass characters, except those related to size, the two sanga breeds, Africander and Barotse, were very similar, as were the two zebu breeds, Angoni and Boran. The introduced breeds, Africander and Boran, which had similar carcass weights, had heavier carcasses (+18 kg, +10%) than the indigenous Barotse and Angoni breeds.The sanga breed carcasses had less fat cover than those of the zebu breeds. Maternal effects were not important for carcass characters and the Angoni/Barotse and Angoni/Boran crosses showed no heterosis. In the Barotse/Boran crosses, slaughter and carcass weights and eyemuscle area gave between 8% and 9·5% heterosis, and the linear carcass measurements between 2% and 3%.It was concluded from the management comparisons that there was no economic advantage in delaying slaughter to the later of the two ages compared in the two year-of-birth groups.
Biometric properties of lactations in ewes raising single or twin lambs
Authors: Torres-Hernandez G. , Hohenboken W. D. 
Published: September 2010

ABSTRACTThe lactation curves of 21 single- (SR) and 28 twin-rearing (TR)ewes were fitted and milk production was estimated by the model Y = axb e−cx, developed in England for dairy cattle. In addition, persistency of lactation of SR and TR ewes was compared using five procedures reported in the literature. Results indicated that the coefficients that characterize the shape of the lactation curve (b and c values) were of similar magnitude to those reported in dairy cattle, thus denning a curve of similar shape. Lactation curves of SR and TR ewes were essentially parallel throughout lactation, with more milk production from TR ewes. The correlation between total milk production estimated by this model and that based on the sum of partial lactations was 0·98, but variability of milk production as estimated by the latter method was slightly less. Lactations of SR ewes had similar persistency to those of TR ewes.