bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies in sow reproduction 5. The effect of lactation length of the sow on the subsequent embryonic development
Authors: Varley M. A. , Cole D. J. A. 
Published: September 2010

SummaryForty-five female pigs (sows) were allocated at random to one of three lactation lengths: 7 days, 21 days, 42 days. All sows were remated at the first post-weaning oestrus and were slaughtered at 20 days post coitum. The reproductive tracts were removed, dissected and examined. Ovulation rates as determined by luteal count were similar for all three groups, but the number of viable embryos decreased significantly (P < 0·05) from 13·0 for the 42-day lactation group to 9·2 for the 7-day lactation group. This difference was reflected in a significant (P < 0·01) reduction in the percentage embryo survival rate as lactation length was reduced. Uterine lengths for the 7-day lactation group were significantly (P < 0·05) shorter than the other two groups. Six sows in each treatment group were blood sampled: at weaning, at remating, at 2 days post-mating, at 10 days post-mating and at 20 days post-mating. The plasma samples obtained were assayed for progesterone. No differences were observed between treatment groups for plasma progesterone concentration at any of the sampling times. It is concluded that the reduction of the litter size at the next farrowing following a short lactation length is largely a result of increased embryo death in the first 20 days of gestation.
Dried sugar-beet pulp as a roughage substitute for pregnant ewes
Authors: Dickson I. A. , Laird R. 
Published: September 2010

SummaryIn 1968-69 for a mean period of 101 days before lambing, 72 cross-bred ewes, and in 1969-70 for a mean period of 88 days, 107 ewes were given roughage daily in the form of (a) 0·91 kg field-cured hay (b) 0·45 kg of hay plus 0·23 kg dried sugar-beet pulp nuts, or (c) 0·45 kg of pulp nuts. Each diet was supplemented by a concentrate allowance. From the 6th week before lambing was due to start, this allowance was progressively and uniformly increased.There was no evidence that the dried sugar-beet pulp had adversely affected performance in terms of ewe body-weight change, lamb numbers, litter weight at birth or 4 weeks of age, fleece weight or general health. It is therefore concluded that dried sugar-beet pulp can be used safely as a replacement for hay in supplying up to 67% of the energy needed for maintenance by ewes.
Tissue growth in the pig
Authors: Cole D. J. A. , White M. R. , Hardy B. , Carr J. R. 
Published: September 2010

SUMMARYGrowth coefficients were determined for muscle, bone and fat in the side and in the ham, for six muscles of the ham, and for the femur, using data obtained from the dissection of 66 carcasses of female pigs weighing from 25 to 65 kg live weight.Irrespective of the independent variable taken for regression, the coefficients showed bone in the side to be earlier developing than muscle, which in turn was earlier than fat. There is good agreement between these coefficients and corresponding values reported for cattle, sheep and pigs.There was little evidence that the ham as a whole or its muscle, bone and fat components grew disproportionately to the corresponding components of the whole side.The growth coefficients of the six muscles of the ham agreed closely with those reported for cattle, sheep and pigs with the exception of that for the m. adductor, which was lower.The combined weights of the m. biceps femoris and m. adductor were related almost as closely to the weight of muscle in the side as was the weight of total muscle in the ham. Of the six muscles taken individually the weight of the m. biceps femoris was most closely related to muscle in the side.
A note on the utilization by calves of maize and potato diets in liquid suspension or in dry form
Authors: Hinks C. E. , Whittemore C. T. 
Published: September 2010

SUMMARYForty British Friesian male calves were pair-fed creep feeds containing 67% of either cooked potato or cooked maize in the form of a dry coarse meal or finely ground in liquid suspension.Although dry maize diets were more acceptable than dry potato diets, daily gains were unaffected by either diet composition or drymatter content.Calves on liquid-fed diets produced faeces of significantly lower dry-matter content.
A note on the relationship between ultrasonic fat measurement and performance in beef cattle
Authors: Moran J. B. , Holmes W. 
Published: September 2010

ABSTRACTThe development of subcutaneous fat as measured by ultrasonics was determined in 28 Angus, 46 Hereford and 42 Charolais bulls, performance-tested on a barley/grass diet. The ultrasonic fat measurements were then examined for possible relationships with feed intake, growth rate and feed conversion efficiency. There were apparent breed differences in the rate of increase in subcutaneous fat thickness with changing live weight but ultrasonic measurements bore little relationship to performance parameters within any of the three breeds tested.
A note on live-weight adjustment for pregnancy in cows
Authors: Silvey M. W. , Haydock K. P. 
Published: September 2010

ABSTRACTSince comparison of live-weight change of breeding cows is complicated by pregnancy and reproductive synchrony, possible analytical methods for overcoming these problems were reviewed. It was concluded that correction of cow live-weight by subtracting the weight of the gravid uterus and products of conception was biologically and practically meaningful. Two exponential models using polynomial coefficients were derived from published data to predict the fresh weights, at any time during gestation, of the foetus (calculated from calf birth weight) and the gravid uterus and foetal membranes and fluids.
A note on the comparative performance of pigs sired by Piétrain × Large White and Large White boars
Authors: Smith W. C. , Toft C. R. , Handscombe N. 
Published: September 2010

ABSTRACTA Piétrain × Large White boar and a Large White boar were placed on each of 12 farms where the breeding females were crossbred white sows. Cooperators were requested to obtain 10 litters by each sire and record their performance to slaughter at 60 kg live weight. Breed of sire did not affect litter size or piglet body weight at birth or at weaning, age of progeny at slaughter, carcass mid-line fat depths or colour and condition of the ‘eye muscle’. Piétrain crosses had higher carcass yields (1·8%) and larger eye muscles in cross-section (13·2%) than Large White crosses. They also had less depth of fat above the eye muscle (14 %) but this did not confer any advantage in commercial evaluations.
Short-term fluctuations in the live weight of identical twin cattle
Authors: Taylor C. S. , Griffiths R. G. , Donald H. P. 
Published: September 2010

ABSTRACTTwo pairs of uniformly treated identical twins were weighed four times daily for 16 days. In addition, daily growth rate was analysed for 10 pairs of identical twins kept on high and low planes of nutrition over a 16-week period.Identical twins fluctuated in body weight from hour to hour and day to day in a significantly more similar manner than did unrelated animals. The greater similarity found when all animals were uniformly treated still persisted when identical twins were placed on different planes of nutrition.
Bull beef production from suckler herds of traditional breed type
Authors: Robertson I. S. , Lowman B. G. 
Published: September 2010

ABSTRACTThe feasibility of producing bull beef in suckler herds of traditional breed type was investigated in two parts. A controlled feeding experiment (Part 1) was carried out with weaned bull and steer calves slaughtered at 398, 432 and 466 kg live weight. Bulls and steers were compared on a standard level of feeding and in addition a group of bulls was given a ration providing a 20% higher daily intake of metabolizable energy. This latter group grew significantly faster than the control bulls and steers, and consumed similar total amounts of metabolizable energy when slaughtered at the same final weight. Carcasses from both groups of bulls were significantly leaner than those of steers. With regard to weight of lean produced per day of age the ranking was bulls on the high energy diet > other bulls > steers.In Part 2 the performance and management demands from birth to slaughter of bulls and steers were compared in a number of spring and autumn-calving herds. Bulls gained live weight more rapidly than steers and although they were taken to heavier slaughter weights their carcasses were significantly leaner. Some readjustment of management practices, e.g. separation of male and female calves with their dams was required. No serious behavioural problems were encountered during the suckling or finishing stages.A consumer acceptance trial showed that, in relation to steaks normally purchased, 61% of local consumers judged bull steaks as average or above in eating quality compared with 91% for steer steaks. It is concluded that although bull beef production is feasible a market outlet is an essential prerequisite.
Studies in sow reproduction 6. The effect of lactation length on pre-implantation losses
Authors: Varley M. A. , Cole D. J. A. 
Published: September 2010

ABSTRACTThirty Landrace × (Landrace × Large White) sows were used to investigate the importance of pre-implantation losses in the embryonic mortality of the early-weaned sow. The sows were allocated at random to one of two lactation lengths, namely, 7 or 42 days. Following weaning and remating the sows were slaughtered at 9 days post coitum. Ovulation rates were similar for both groups (15·3 and 15·1 for the 7-day and 42-day weaned groups respectively). Numbers of embryos present at 9 days post coitum were 12·5 for the 42-day group and 11·2 for the 7-day group and the difference was non-significant. Percentage embryo survival was 83·5% for the 42-day group and 74·3% for the 7-day group; the difference was non-significant. It was concluded that the bulk of embryo loss in the early-weaned sow occurred after the pre-implantation stage and was probably at or around implantation.
The performance of sows and litters penned individually or grouped in late lactation
Authors: Petchey A. M. , Dodsworth T. L. , English P. R. 
Published: September 2010

ABSTRACTPiglets in litters reared in groups from 3 to 7 weeks of age weighed less at weaning (7 weeks) than piglets in which litters were penned individually. Some of the difference between the two management systems was created within the week after grouping. Grouping sows and their litters did not initiate oestrus in lactation. The subsequent litter size of the grouped sows was reduced but between-treatment differences for this trait failed to reach significance at the 5% level.
A time-controlled feeding system for cattle
Authors: Shaw R. A. 
Published: September 2010

ABSTRACTA system of time-controlled feeding has been developed to give a considerable degree of control over the food intake of animals without eliminating individual variation.The system is based on the Calan-Broadbent electronic feeding doors and animals are conditioned by certain electrical and sound stimuli to use the doors only during prescribed periods. Clock mechanisms control the time intervals when electric power to the doors is on or off.Times and durations of feeding can be adjusted so that a predetermined level of intake is obtained, and a heavy demand on labour is avoided.In the present trial, British Friesian and Jersey cattle on a time-controlled feeding regime were compared with animals given access to food ad libitum. A significant reduction in food intake due to time-controlled feeding was detected in both breeds over a 6-month period.There was no evidence to suggest that the particular time-controlledfeeding regime restricted one breed more than the other.
Substitution rates in steers fed on low quality grass hays supplemented with maize grain
Authors: Torres F. , Boelcke Cristina 
Published: September 2010

ABSTRACTTo estimate the effect of supplementation on hay: grain substitution rates, 18 experimental rations were evaluated in digestibility trials, each using four steers (300 kg live weight) housed in metabolism stalls. Four hays (digestible dry matter = 40 to 62 %) were given to appetite, supplemented with maize grain plus urea at several different levels, up to 2·5% of animal live weight, and substitution rates were estimated as the slope of the linear regression of hay intake on grain intake. General substitution rates were independent of hay quality, and the pooled rate was 830 g (Sb = 0·036) per kg of grain dry matter. Nevertheless, the analysis of the observed partial substitution rates and those in the literature, suggests a possible interaction between the effects of hay digestibility and grain level on substitution rates.
Effect of dietary lysine levels on performance, nitrogen metabolism and plasma amino acid concentrations of lactating sows
Authors: Chen S. Y. , d'Mello J. P. F. , Elsley F. W. H. , Taylor A. G. 
Published: September 2010

ABSTRACTDuring lactation 30 sows were given a basal diet containing 0·39% lysine or the same diet supplemented with 0·1, 0·2, 0·3 or 0·4% Llysine. In addition a group of six sows was given a high protein/high lysine control diet containing 17% crude protein and 1·06% lysine. Piglet weight gain, sow milk yield, milk contents of total solids, protein, fat and energy and efficiencies of utilization of energy and protein for milk production increased progressively as dietary lysine levels were raised to 0·59 %. Sows receiving the lysine-supplemented diets had markedly higher efficiencies of conversion of dietary protein into milk protein and lower efficiencies of energy utilization than those given the high protein/high lysine control diet.Nitrogen retention and biological value of the dietary protein increased quadratically with increasing dietary lysine concentrations, reaching maximum values at 0·59% lysine.Apparent digestibilities of isoleucine, lysine, methionine, threonine and valine in the basal diet were closely correlated with digestibility of nitrogen. Plasma lysine concentrations remained depressed and relatively constant at low dietary levels of lysine, but increased sharply at 0·59 % dietary lysine coinciding with a marked drop in circulating concentrations of other essential amino acids.
Changes in the body composition of cattle exhibiting compensatory growth and the modifying effects of grazing management
Authors: Baker R. D. , Young N. E. , Laws J. A. 
Published: September 2010

AbstractFriesian steer calves born in August were reared from 3 to 7 months of age on either a low (OL) or high (OH) plane of nutrition. A further group born in October (YH) was also reared on a high plane. At grazing, the performance of calves of the same age but different weights (OL v. OH) or the same weight but different ages (OL v. YH) were compared at two levels of herbage allowance, either 30 or 60 kg dry matter per kg live weight. During the winter, the H groups received silage and concentrate and the L group was given silage only. The OL group had a higher concentration of fat and a lower concentration of water in the empty body at the end of the winter than did the OH and YH groups respectively.Compensatory growth was exhibited by the OL group at both herbage allowances. Differences in the live-weight and empty body-weight gains of OL and OH cattle could be explained almost entirely by differences in the energy content of the gains whereas this was only partially so when the OL and YH groups were compared. The results indicate that YH cattle had lower herbage intakes even though they were of similar weight to OL cattle.It was concluded that silage nitrogen is used less efficiently by cattle than is generally assumed and that the levels of gut fill and energy content of the live-weight gains in this experiment were not consistent with the general values suggested by the Agricultural Research Council (1980).
The effects of level of maize gluten feed in the diet on pig performance and carcass quality
Authors: Edwards Sandra A. , Prescott Nicola J. , MacDougall D. B. 
Published: September 2010

AbstractDiets containing 0, 100, 200 or 300 g/kg of maize gluten feed were formulated, using standard tables of ingredient values, to have similar levels of digestible energy (12·9 MJ/kg) and lysine (8·9 g/kg). Each diet was scale fed to four pens of eight pigs, entire males and females, from 37 kg until slaughter at about 85 kg.There were no problems with diet palatability and no significant differences in live-weight gain, food conversion efficiency or killing-out proportion. With increasing maize gluten feed, dietary lysine increased (8·5, 8·6, 8·9, 9·0 g/kg) and backfat thickness decreased (P1 + P3 = 28·6, 27·2, 25·5, 24·9 mm, P < 0·05). Fat samples were taken from the last rib position on each side of all carcasses. With increasing maize gluten inclusion the fat (inner layer) became darker (P < 0·001) and yellower (P < 0·05). Increasing maize gluten feed also increased levels of linoleic acid (170·4, 195·8, 224·8, 247·7 g/kg total fatty acids; P < 0·001) indicating that progressively softer fat would be produced. The results show that inclusion rates of maize gluten feed up to 300 g/kg did not adversely influence pig performance or carcass characteristics but the appearance and keeping quality of the fat might be adversely affected by higher levels.
Variance of body weights and daily weight gains of weaner pigs housed at various stocking densities in confinement
Authors: Kornegay E. T. , Notter D. R. , Bartlett H. S. , Lindemann M. D. 
Published: September 2010

AbstractBody weight and gain data from eight studies conducted with weaner pigs to determine the relationship between stocking density and performance were used to evaluate the effect of various stocking densities on several factors which measure variation within pens. The initial weight of the pigs ranged from 5·7 to 8·3 kg and final weight ranged from 17·7 to 32·1 kg. There were 244 pens of pigs with floor space ranging from 0·11 to 0·28 m2 per pig. Average daily gain and body weight were depressed as stocking density increased. Natural logarithms of variance, coefficients of variation and ranges of average daily gains and body weights were not increased by stocking density. Body weights and daily gains appeared equally effective in measuring variance of weaner pigs housed at various densities. These results indicate that increasing stocking density within the range of densities tested does not cause a greater variation in body-weight gains.
Scope for selecting many breeding stocks of possible economic value in the future
Authors: Smith C. 
Published: September 2010

AbstractCurrent animal improvement deals largely with selection of stocks for current economic objectives. However, there is uncertainty about how well these objectives will hold in the future, since husbandry and marketing needs and conditions may change unpredictably over time. The scope for developing alternative stocks, selected for different chosen sets of objectives, is considered, so that by substitution or crossing it may be possible to reduce the uncertainty and better meet future needs and conditions. The reduction in uncertainty is modelled by including risk or uncertainty in the discount rate in assessing benefits over time from one cycle of selection. From the national viewpoint, the costs of developing alternative selection stocks are small relative to the possible returns. Thus, if the uncertainties were reduced by having them, a large number of such alternative stocks would be justified. The expected benefits to the community from animal breeding would also be increased thereby.
A note on the critical temperature of the fasted and fed early-weaned pig
Authors: Jordan J. W. , McAllister A. , Weatherup S. T. C. 
Published: September 2010

AbstractThe heat production of fasted and fed littermate pairs of pigs weaned at 10, 17 and 24 days of age was determined between 16 to 34°C. Up to and including 34°C the post-weaning heat production of fasted pigs at 10 and 17 days of age decreased with rising temperature. Rectal temperatures of all 24-day-old fasted pigs were higher at 34°C than at 31°C. For fed pigs weaned at 10 days of age the heat production continued to decrease up to and including 34°C. The decrease between 28°C and 31°C and between 31°C and 34°C was comparatively small and rectal temperatures were slightly elevated at 34°C. The results indicated that for fed pigs weaned at 17 and 24 days the thermoneutral zone was in the region of 31°C and the lower critical temperatures were about 28°C.
Influence of liver fat on post-partum hormone profiles in dairy cows
Authors: Watson Elaine D. , Williams Linda A. 
Published: September 2010

AbstractCows (no. = 11) were classified from liver biopsies taken 7 to 10 days after calving as having mild (FL1, no. = 6), or moderate (FL2, no. = 5) fatty infiltration of the liver. Blood samples were collected from the jugular vein: (1) three times weekly and assayed for progesterone and oestradiol; (2) at 10-min intervals for 8-h periods on three occasions during the early post-partum period and assayed for LH; (3) every 2 h, with ovarian palpation performed every 4 h around the second or third post-partum ovulation, and assayed for LH and oestradiol.Mean weekly concentrations of oestradiol were not significantly different between FL1 and FL2 cows. FL2 cows tended to have short (< 17 days) first cycles (3/4 FL2 v. 0/5 FL1) with significantly lower concentrations of plasma progesterone (P < 0·05). Mean basal concentrations of LH in the samples collected at 10-min intervals tended to be lower in FL2 than in FL1 cows; however, the difference was significant only in the 2nd week of sampling (P = 0·05). Mean basal concentrations of LH were significantly higher in weeks 3 and 4 than in week 2 in FL1 but not in FL2 cows (P < 0·05). The frequency and amplitude of LH pulses were not affected by week of sampling or by fat content of the liver. The total area under the profile of LH during the pre-ovulatory surge was lower in FL2 than in FL1 cows (P < 0·05) but peak plasma concentrations of pre-ovulatory oestradiol and timing of ovulation after the LH surge were similar.
Cereal straw in diets for beef cattle: effects of pattern of growth and diet formulation on growth rate and food conversion efficiency
Authors: Macdearmid A. , Williams P. E. V. , Brewer A. C. 
Published: September 2010

AbstractFive groups of Hereford × Friesian steers (initial weight 340 kg) were given either a diet of rolled barley and ammonia-treated barley straw (AS) in the ratio 60: 40 ad libitum (ASB) to support continuous growth, or were offered over a 143-day period diets of either (i) AS alone (diet AS) (ii) untreated straw (US) plus cassava (diet USC) (iii) US plus grass silage (diet USS) or US plus fish meal (0·27 kg fish meal per day) (diet USF). Both the AS and US were offered ad libitum and allowances of cassava and silage adjusted to allow the USC and USS steers to match the growth of AS steers. Steers i n the restricted groups (AS, USC, USS and USF) were then given freshly cut grass ad libitum until they reached slaughter weight; some steers required additional hay and barley to reach slaughter weight. Steers in group ASB consumed 7·4 kg dry matter (DM), gained 1·16 kg live weight per day taking 112 days to achieve the 455 kg slaughter weight. AS, USC and USS animals maintained body weight over the restricted period, whereas the USF group tended to lose weight and daily DM intakes were 4·63 kg AS (AS steers); 3·81 kg US plus 0·95 kg cassava (USC steers); 0·86 kg US plus 3·31 kg silage (USS steers); 3·5 kg US plus 0·27 kg fish meal (USF steers). When grass or grass followed by barley plus hay was given the live-weight gains of the previously restricted cattle did not differ (mean 1·0 (s.e. 0·10) kg/day). AS provided proportionately 0·30 of the metabolizable energy used to produce growth rates in excess of 10 kg/day or if given as the sole food maintained cattle without supplementation.