bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of breed and sex on the allometric growth patterns of major bovine tissues
Authors: Mukhoty H. , Berg R. T.
Published: September 2010

The influence of breed and sex on relative growth patterns of muscle, bone and fat in beef cattle has been investigated. Comparisons were made of growth coefficients estimated using Huxley's (1932) allometric equation relating muscle, bone or fat to muscle plus bone using data from the dissection of half carcasses of 63 young bulls, 106 steers and 22 heifers representing a number of breed groups. Growth coefficients for muscle and for bone were found to be similar among different breed groups of bulls, steers and heifers. The proportion of muscle increased and that of bone decreased as the size of animal, measured by muscle plus bone, increased. Muscle and bone weights adjusted to common muscle plus bone weights were significantly different among breed groups within sex. Differences in amount of muscle relative to bone were therefore established at earlier stages of growth and maintained over the period represented in the present study.

Growth coefficients for fat were significantly different among breed groups within sexes.

Sex within breed group had no statistically significant influence on growth coefficients for muscle or for bone. Muscle and bone weights adjusted to a common muscle plus bone weight were similar for sex groups within all breed group comparisons. Sex did not have a marked effect on rate of fattening since differences between growth coefficients for fat (between sexes, within breeds) were not statistically significant—although in all comparisons growth coefficients for fat were lowest for bulls, intermediate for steers and highest for heifers. Sexes differed in weight of fat adjusted to common muscle plus bone weight, heifers being fatter than steers and steers fatter than bulls, a difference probably resulting more from early onset of the fattening phase in heifers, followed by steers, rather than relative rate of fattening.
Artificial insemination and natural service at a predetermined time in cyclic sheep treated with ‘SC-9880’-progesterone sponges
Authors: McClelland T. H. , Quirke J. F.
Published: September 2010

Results are given of an experiment in which 61 cyclic Finnish Landrace × Dorset Horn ewes were synchronized for oestrus by intravaginal treatment for 14 days using sponges impregnated with 30 mg ‘Cronolone’ (9a-fluro-11-hydroxy-17a-acetoxy-progesterone; SC-9880, G. D. Searle) and 400 mg progesterone. Groups of 31 and 30 sheep were inseminated twice, either artificially or naturally, at predetermined intervals of 48 and 58 hr after sponge withdrawal. All 61 ewes were in oestrus within 48 hr of removing sponges; 26 of 30 (87%) artificially inseminated and 29 of 31 (94%) hand-mated sheep conceived at the controlled oestrus. The incidence of multiple births was not significantly affected by the method of breeding.
Genetic and phenotypic parameters of body weights in Bikaneri sheep (Magra strain)
Authors: Chopra S. C. , Acharya R. M.
Published: September 2010

Heritabilities of birth, weaning, 6-month and yearling weights adjusted for significant non-genetic factors and obtained from half-sib correlations were 0·10±0·03, 0·22±0·05, 0·37±0·09 and 0·48±0·07 respectively. Genetic correlations of birth weight with later weights were small and negative except with weaning weight. Genetic correlations among other weights were large and positive. The phenotypic correlations among these weights were positive and statistically highly significant.
A note on the performance of artificially reared lambs fed cold milk substitute from birth to slaughter
Authors: Penning P. D. , Bradfield P. G. E. , Treacher T. T.
Published: September 2010

Two groups of five lambs were removed from their dams within 48 hr of birth and artificially reared to a slaughter weight of approximately 32 kg on a milk replacer given cold, hay and concentrates. Voluntary intake of the feeds was recorded together with growth rates and carcass composition of the lambs.

The two groups of lambs were slaughtered at 58 or 67 days of age with growth rates of 459 and 433 g/day, respectively. The mean milk replacer dry matter consumed per lamb was 34·9 kg and 39·3 kg and concentrate dry matter intakes were 3·1 kg and 4·1 kg. Intakes of hay were negligible. Food conversion efficiencies were 0·70 and 0·67 kg of live-weight gain per kg of dry matter consumed. The mean carcass weights were 18·1 kg and 19·5 kg with mean muscle, bone and fat contents of 48·7%, 16·2% and 35·1 % for lambs slaughtered at 58 days and 48·0%, 14·7% and 37·2% for those slaughtered at 67 days.
The energy and protein metabolism of pigs growing at a high ambient temperature
Authors: Holmes C. W.
Published: September 2010

1. The experiment was designed to investigate the effect of growth at a high ambient temperature, 33–35°C, on the protein and energy metabolism of pigs, compared with 25°C. The high temperature caused an increase in rectal temperature of 1·4° to 1·7°C. The animals were given two low levels of feeding while growing between 25 and 70 kg live weight; energy and nitrogen retention were measured periodically.

2. The apparent digestibilities of the dietary dry matter and energy were decreased and urinary nitrogen losses were increased at the high temperature. Heat production was increased at the high temperature, by between 2% and 10%, the effect becoming more pronounced during the course of the experiment. Retention of energy and nitrogen was reduced at the high temperature.

3. The net efficiency of utilization of metabolized energy above maintenance was between 63% and 67%, and was not significantly affected by live weight or temperature. The results suggested that maintenance requirement was increased at the high temperature.

4. Analyses of sample joints indicated that the high temperature caused an increase in fat percentage only at the higher level of feeding; this result agreed with fat and protein retention calculated from the balances.
The utilization by beef cattle of a cereal supplement given in liquid suspension or in the dry form
Authors: Renton A. R. , Forbes T. J.
Published: September 2010

An experiment was carried out in which a cereal supplement was given to beef cattle, either in suspension in water or as a dry supplement. There were no significant differences between treatments in live-weight gain, food intake or food conversion ratios. Although there was a tendency for the digestibility coefficients of all constituents to be lower on the diet containing the liquid supplement, the differences were not statistically significant. It is concluded that giving a supplement in suspension has no adverse effect on the utilization of the overall diet and could facilitate mechanization of the feeding operation.
Variation in the concentration of copper in the blood plasma of Finnish Landrace and Merino sheep and their crosses with reference to reproductive performance and age
Authors: Hayter Susan , Wiener Gerald , Field A. C.
Published: September 2010

Concentrations of copper in blood plasma were determined in January and in February 1971 and in February and March 1972 in a grassland flock of sheep comprising the Finnish Landrace and (Tasmanian) Merino breeds and their reciprocal crosses. Numbers of animals ranged from 30 to 100. The unadjusted mean copper levels of the flock varied from 63 to 81 μg/100 ml. The Finnish Landrace had a markedly lower plasma copper concentration than did the Merino, the mean difference after adjustment for other factors varied from 16 to 54 μg/100 ml. First crosses had levels halfway between those of the parental breeds. Copper concentration fell in the 4-week period between February and March 1972 when most of the ewes were pregnant. This fall was greatest for the Finnish Landrace which started with the lowest level and least for the Merino.

Neither the breed differences in the change in level nor the actual concentration appeared to be related to the number of lambs (0 to 4) carried by the ewes. Variation in copper level associated with the age of ewe, significant for the two bleedings in 1972, was largely attributable to the higher level among the youngest age class, approximately 10 months old when bled. The stage of pregnancy at the time of blood sampling, as reflected by date of lambing, did not significantly affect plasma copper concentration in this flock.
Cold-induced inhibition of thermal panting in shorn sheep. 1. Effect of intensity of cold exposure
Authors: Slee J.
Published: September 2010

The delayed onset of heat-induced panting (at 42°C) immediately following previous shearing and exposure to cold was studied in 54 Scottish Blackface and 53 Tasmanian Merino sheep.

In control sheep (not previously cold-exposed) thermal panting commenced in 15 min. In cold-treated sheep, when the cold was intensified stepwise from +26°C (+30cC being thermoneutral) down to −10°C, using 2-hr exposures, or lengthened from 2 hr to 16 hr at +8°C, the delay (block) to panting increased non-linearly from 40 to 70 min.

The minimum intensity of cold required to produce a block (26°C in Merinos, 22°C in Blackfaces) was similar to that inducing peripheral vasoconstriction. More intense vasoconstriction preceded longer blocks, but vasoconstriction sometimes occurred without a subsequent block.

Merinos were more sensitive than Blackfaces to the blocking effects of cold, and, once blocked, the effect in Merinos was less easily removed by re-warming.

The time taken for cancellation of the heat debt during heat stress could account for half the block. The remainder, a delay of about 30 min, was attributed to a specific inhibition of respiratory control in the central nervous system.
A note on the genetic variation in the fatty acid composition of cow milk
Authors: Edwards R. A. , King J. W. B. , Yousef I. M.
Published: September 2010

The fatty acid composition of milk samples from Ayrshire twin cows was determined. The results were in general agreement with those reported by other workers. Comparisons between the variation within pairs of one and two-egg twins showed that the proportions of different fatty acids are subject to a high degree of genetic control.
Rearing of dairy cattle. 4. Effect of concentrate supplementation on the live-weight gain and feed intake of calves offered roughages ad libitum
Authors: Leaver J. D.
Published: September 2010

The effects of three levels of concentrate supplementation on the live-weight gain and intake of roughages of 12-week-old British Friesian female calves were examined. Each supplement was offered for 12 weeks to two replicates of five calves which were group fed. The following six roughages were studied; high quality hay, dried grass wafers, grass silage, barley straw, poor quality hay and maize silage. The digestibility of the roughages was measured with sheep by total collection of faeces.

Increasing the level of concentrate supplementation gave linear increases in live-weight gains of calves with all roughages, the greatest response occurring with roughages of low digestibility. The intake of roughage was depressed by increasing the level of concentrate supplementation, the greatest depressions occurring with roughages of high digestibility. Live-weight gains and roughage intakes were higher with dried grass wafers and lower with maize silage than would be expected from their respective digestibility coefficients.

Multiple regression equations were calculated to relate live-weight gains or roughage intakes to concentrate intake and roughage digestibility. These equations predict from the digestibility of a roughage, the amount of concentrates required daily to produce a given live-weight gain, and the amount of roughage which is eaten under these circumstances.
Cereal processing and food utilization by sheep. 3. The effect of replacing whole barley by whole oats on food utilization and firmness and composition of subcutaneous fat
Authors: Ørskov E. R. , Duncan W. R. H. , Carnie Constance A.
Published: September 2010

1. Forty-eight early-weaned lambs were used in an experiment in which whole barley was gradually replaced by whole oats in order to produce different types of rumen fermentation.

2. The type of rumen fermentation promoted by whole barley did not give rise to excessively soft fat in female lambs; in males, however, some carcasses were unacceptable. An increase in the proportion of propionic acid in the rumen liquor was associated with an increased proportion of odd- and branched-chain fatty acids and a decreased proportion of stearic acid in carcass fat. When the molar proportion of propionic acid in the rumen liquor was above 30%, three out of every five carcasses from the entire male lambs had excessively soft fat.

3. Assessment of food utilization was complicated by lower daily intakes of digestible organic matter (DOM) when more than about 15% of barley was replaced by oats and also influenced by changes in gut contents. With 100% whole barley the mean gut fill was 4·7 kg while with 100% oats it was 9·4 kg.

Assuming a maintenance requirement of 100 kcal metabolizable energy/kg0·75, it was calculated that the digestible organic matter of oats was utilized more efficiently than that of barley to produce empty-body gain. Most of the differences in utilization disappeared if an adjustment was made for differences in gut contents. The results indicate that the maintenance requirement/kg0·75 decreases with increasing gut content.
The effect of straw on the behaviour of sows in tether stalls
Authors: Fraser D.
Published: September 2010

The behaviour of sows in tether stalls with and without straw was studied in two experiments. Sows lay down more when 1 kg of straw was provided daily, especially when it was chopped and mixed wet with the food (dietary effect). Sows without straw performed avariety of stereotyped oral and other activities which were greatly reduced by the provision of loose straw that could be chewed and manipulated throughout the day (recreational effect). Sows were frequently seen standing or sitting motionless with the head drooping, probably in a state of drowsiness. This behaviour was virtually eliminated by full straw bedding (bedding effect). Certain ‘comfort movements’, barbiting at feeding time, and biting the neighbouring sows, were not influenced by straw. It is concluded that the dietary, recreational and bedding aspects of straw are all significant, but influence different aspects of the animals' behaviour. The significance of bar-biting and other activities is discussed.
A note on porcine skeletal muscle parameters and their possible use in early progeny testing
Authors: Stickland N. C. , Goldspink G.
Published: September 2010

An ‘indicator muscle’ (m. flexor digiti V brevis) was removed in its entirety from several Large White and Landrace pigs of varying fat depth (measured over the eye-muscle area). The total muscle fibre number was measured in transverse sections for each muscle. Significant inverse relationships were found between this fibre number and fat depth measurements. These and other results suggest that fibre number is related to lean meat content. Fibre number was also shown to be highly correlated with fibre density and as thinner fibres (i.e. higher fibre density) are associated with more tender meat, fibre number may be associated with quality as well as quantity of meat.
Prediction of comparative retail value of beef carcasses
Authors: Harries J. M. , Williams D. R. , Pomeroy R. W.
Published: September 2010

An attempt to evaluate a group of 72 beef carcasses, in retail terms, is described, resulting in a comparative measure of retail value that takes account of saleable fat and of the distribution of lean amongst the different cuts. Changes in the general level of beef prices can be discounted, provided the ratios of the prices of different joints remain the same. It was found that the index of retail value was poorly correlated with the commonly used ratio of high-priced to low-priced parts, but highly correlated with total proportion of lean. The index could best be predicted from a multiple regression on side weight and proportional area of muscle determined from photographs of the cut surface after quartering.
Value of lucerne cobs for milk production
Authors: Archibald K. A. E. , Thomson E. F. , Campling R. C.
Published: September 2010

Three changeover experiments, each with 16 milking cows, were conducted to evaluate the effects of stage of growth of lucerne, level of feeding of lucerne or ryegrass and level of inclusion of barley. The artificially dried and processed forages were in the form of cobs and given to cows in addition to a basal ration of hay. Late-cut lucerne (organic matter digestibility, OMD, 55%) promoted significantly lower milk yields than early-cut lucerne (68% OMD). When offered ad libitum in two meals each day both forages were eaten in quantities of about 13 kg dry matter. Ryegrass cobs (79% OMD) produced more milk than lucerne cobs (59% OMD) but gave similar milk yields per unit of digestible organic matter. Production rations supplying similar amounts of digestible organic matter and composed of different proportions of lucerne cobs and rolled barley gave similar milk yields. It is concluded that the relative milk-producing value of processed forages depends on their content of digestible organic matter. However, their bulk may limit their value and the inclusion of cereal with the dried forage may be worth while.
Performance of purebred and crossbred dairy cattle in Thailand
Authors: Madsen Ove , Vinther Knud
Published: September 2010

Reproductive and production traits were studied in a crossbreeding experiment involving Red Danish cattle, Indian milch breeds and native Zebu cattle in various combinations.

Frequency of abortions and postnatal mortality were higher for Red Danish than for Indian milch breeds and crossbreds, age at first calving was higher for Indian milch breeds than for other groups, calving interval was longer for purebreds than for crossbreds. Milk and butterfat production in first and second lactation increased with increasing proportion of genes from Red Danish cattle. The range of milk production in first lactation was from 987 kg for Indian milch breeds to 3445 kg for Red Danish imported from Denmark.

The optimum proportion of genes from Red Danish for the environmental conditions prevailing in the present crossbreeding experiment is considered to be 60 to 80%.
Prediction of the digestible energy in pig diets from analyses of fibre contents
Authors: King R. H. , Taverner M. R.
Published: September 2010

Digestible energy (DE) values were determined for 15 pig diets with pigs 8 to 18 weeks old by standard digestibility procedures. The 15 diets contained 4360 to 4920 kcal gross energy (GE)/kg dry matter (DM), 2750 to 4070 kcal DE/kg DM, 2·8 to 15·8% crude fibre (CF), 2·4 to 21·1% acid-detergent fibre (ADF), and 7·3 to 33·8% neutraldetergent fibre (NDF).

The prediction equations obtained were all highly significant. DE was most accurately predicted when the fibre value used was NDF, the regression equation being: DE = 4314·37·22 NDF (residual SD + 265). The inclusion of GE in the regression equation considerably improved its accuracy: DE = 1·510 GE-2579·39·37 NDF (residual SD ±127).

However, the greater digestibility by pigs of NDF in diets containing sweet lupin seed meal (SLSM) resulted in these diets being more efficiently digested than diets containing other common protein supplements. Omitting the four diets containing SLSM from the regression analysis resulted in an even more accurate prediction equation: DE = 1·177 GE-1085·40·22 NDF (residual SD±107). It is suggested that this equation may be used to predict DE of pig diets compounded from commonly used constituents.
The effect of dietary concentrations of digestible energy on the performance and carcass characteristics of early-weaned pigs
Authors: Campbell R. G. , Taverner M. R. , Mullaney P. D.
Published: September 2010

Fifty-four pigs weaned at 3 weeks of age were allocated at an average weight of 5·4 kg to two experiments to examine the effects of diets having digestible energy (DE) concentrations ranging from 2910 to 3940 kcal/kg.

In the first experiment pig growth performance and the dry-matter digestibility of the experimental diets were measured between 3 and 8 weeks of age. The composition of the carcass at 8 weeks of age was correlated with the composition of various carcass joints.

In the second experiment pig growth performance was measured over the live-weight range 5-4 to 20 kg.

The findings were:

1. Growth rate was linearly related to DE intake.

2. The optimum DE level for maximum growth was 3640 kcal/kg.

3. The efficiency of utilization of DE for growth did not vary in the first experiment but was poorest at a DE concentration of 3245 kcal/kg in the second.

4. The DE content of the diet had no significant effect on carcass characteristics at 8 weeks of age in the first experiment or at 20 kg live weight in the second.

5. The proportion of fat and lean in the 8-week carcass was significantly (P < 0·01) correlated with that of the shoulder joint.
Effect of concentrate level and stocking rate on performance of dairy cows calving in late winter
Authors: Gordon F. J.
Published: September 2010

A 2 × 2 factorial design experiment was conducted for 2 years using 72 British Friesian cows to assess the effects of two levels of concentrate input (822 and 610 ± 13·7 kg/cow) and two stocking rates (6·4 and 4·9 cows/ha) on animal performance. The animals, which had a mean calving date of 22 January, were blocked according to calving date and allocated at random to treatments within each block.

All concentrates were given during the post-partum, indoor-feeding period in addition toad libitumgrass silage. All animals received equal concentrate inputs/kg milk produced for the first 4 weeks after calving following which the input to the low concentrate animals was reduced. The animals went to pasture during mid-April and were rotationally grazed for a 24-week period. The pasture received 450 kg N/ha. No interaction between concentrate input and stocking rate was found. The mean milk outputs during the winter period were 2064 and 1971 ±23·9 kg, during the grazing period 2679 and 2739 ± 53·2 kg, and during the total lactation 4991 and 4984 ± 78·8 kg for the high and low concentrate groups respectively. The mean live weights for the two groups were 515 and 496 + 3·1 kg at the end of the winter period and 549 and 537 ± 4·1 kg at the end of the grazing season. The mean values for the high and low stocking rates respectively were: output/cow at pasture, 2571 and 2847 ± 53·2 kg; total lactation yield, 4804 and 5170 + 78·8 kg; live weight at end of grazing season, 529 and 558 + 4·1 kg. Milk composition data are also presented.
Soaking of complete fattening rations high in poor roughage 3. The effect of moisture content and spontaneous fermentation on the performance of male cattle
Authors: Holzer Z. , Levy D. , Tagari H. , Volcani R.
Published: September 2010

Two trials were conducted with two complete fattening diets contain- ing 25 and 45 % fibrous roughage, to examine the effects of three moisture levels and five soaking conditions on the performance and ruminal fermentation of fattening cattle.

Differences between treatments in live-weight gain and carcass-weight gain were not significant but there were differences in the efficiency of conversion of metabolizable energy into live weight and into carcass weight and in some instances these were significant. There was a trend towards increased weight of kidney, pelvic and cod fats and a slight decrease in weight of other fat trim of the carcass (subcutaneous and intermuscular) on the treated diets, as compared with the dry control diet.

The pH of the rumen liquor of animals given the soaked rations was lower and the total volatile fatty acid concentration higher than that of animals receiving the dry control diet. The propionic acid concentration in rumen liquor was significantly higher in animals receiving moistened diets.
Development of a synthetic pig sire line by selection with immigration 1. Results of selection and heritability estimates
Authors: Webb A. J. , King J. W. B.
Published: September 2010

Starting in 1959 from a crossbred foundation, a specialized synthetic sire line has been developed with the aim of making rapid genetic improvement in lean meat production. Within-line selection, firston ultrasonic backfat and then on a performance index, was supplemented over 11 generations by a process of competitive immigration, in which individuals of any breed from outside were incorporated into the line on merit. By Generation 11 the Sire Line contained genes from 9 pure breeds and 2 hybrid strains.

After a rapid initial phenotypic decline in backfat, there was little apparent response to index selection. In Generation 11, a centrally tested sample of the Sire Line showed significant improvements over contemporary Large Whites in growth rate, feed efficiency, eye-muscle area, lean percentage and some fat depths, but was significantly worse in killing-out percentage. With the exception of teat number there was no evidence of a decline in reproductive performance, to which no attention was paid during selection. Estimated heritabilities of growth rate and backfat were not sufficiently different from those reported for purebred pig populations to indicate that additive genetic variance had been changed by mixing breeds. Some of the advantages and disadvantages of the ‘open synthetic’ method of genetic improvement are discussed.
Urea phosphate as a partial protein replacer in sheep concentrate diets
Authors: Tagari H. , Ben-Ghedalia D. , Zamwel S.
Published: September 2010

Incubation with rumen liquor gave a lower rate of release of ammonia and a higher dehydrogenase activity with urea phosphate (UP) than with urea.

Four concentrate diets containing 13 % crude protein, 27% of which was supplied by urea or three different forms of UP, were each given to eight Awassi lambs. With twice-daily feeding (but not five-times daily feeding), a beneficial effect of UP over urea was observed, expressed in lower blood ammonia and urea levels. There was no effect on the pH of rumen liquor.

In a N-balance experiment with 24 lambs, four diets were examined: a basal diet containing 9·5% crude protein and three other diets in which the crude protein content was raised to 13% by addition of soya bean meal, urea or UP. The diets were given twice daily. Urea phosphate and the soya bean meal gave a significant increase in N retention whereas the urea treatment did not. However, the difference in N retention between the UP and urea treatments was not significant. Total volatile fatty acid concentrations in the rumen did not differ significantly between treatments but the ratio of acetic to propionic acids was significantly lower with the urea diet.
Nutritional evaluation of wheat. 5. Disappearance of components in digesta of pigs prepared with two re-entrant cannulae
Authors: Ivan M. , Farrell D. J.
Published: September 2010

1. Three pigs prepared with re-entrant cannulae in the proximal duodenum and terminal ileum were used to study flow rate of nitrogen, and digestion and absorption of dry matter, nitrogen, gross energy and starch. The pigs were given a semi-purified diet, a hard wheat diet and a soft wheat diet. These were approximately isonitrogenous.

2. Nitrogen content of insoluble dry matter of duodenal digesta was much higher on the semi-purified diet than on the wheat-based diets.

3. Apparent digestibilities of dry matter, energy and nitrogen in the small intestine were in the order semi-purified diet > hard wheat > soft wheat although differences were not statistically significant. Similar results were obtained for total digestibility of these components.

4. Absorption of most amino acids from the small intestine was higher for casein in the semi-purified diet than for wheat protein. Significantly more lysine, arginine, isoleucine and tyrosine were absorbed from hard than from soft wheat.

5. With all diets there was almost complete digestion of starch in the small intestine.

6. There was little digestion of nutrients in the large intestine, and thus digestibilities calculated from faecal analyses showed similar trends to those calculated from analyses of digesta from the terminal ileum. Most values compared favourably with those reported elsewhere for digestibilities of amino acids in wheat.

7. It was concluded that casein was superior to the wheat proteins but that protein of hard wheat was of better quality than that of soft wheat when evaluated by ileal recovery of animo acids, due largely to a greater absorption of lysine.
The utilization of whole or bruised barley grain of different moisture contents given to beef cattle as a supplement to a forage-based diet
Authors: Broadbent P. J.
Published: September 2010

1. Fifty-four weaned single-suckled steer calves aged 11 to 14 mo were individually fed 2 kg wet distiller's grains, 10 kg swedes and an average of 11·5 kg grass silage daily. The quantity of silage offered was adjusted during the experiment in accordance with a live weight related scale. There were six treatments differing in the physical form, moisture content and level of barley grain offered. A nil barley supplement was compared with 2·5 kg barley dry matter daily offered either whole or bruised having been prepared for storage by drying (84·6% DM) and by treatment with propionic acid (79·9% DM); dried barley was also offered whole (at approximately 50% DM) after soaking in water for 24 hr. Each replicate of six cattle, one animal from each treatment, was slaughtered when all its members were subjectively estimated to have the required minimum body condition and minimum estimated carcass weight (186 kg) for marketing.

2. A supplement of barley grain caused increases in daily live-weight gain, slaughter weight, carcass weight and carcass fat content; and reduced carcass lean and bone content. These effects were increased if the barley grain was processed by bruising compared to being consumed unprocessed (whole). There was no indication that the method of preparation for storage or the moisture content of the barley grain when consumed affected the results of the experiment. It was concluded that the costs of processing barley grain by bruising for feeding to growing cattle for slaughter will be exceeded by the value of the additional animal performance obtained in comparison to feeding whole barley grain.
Soaking of complete fattening rations high in poor roughage. 4. The effect on deposition and fatty acid composition of bovine fat
Authors: Holzer Z. , Tagari H. , Levy D. , Volcani R.
Published: September 2010

The effects of diets containing variable percentages of roughage and moisture on depot fats were studied. Treatments were 25 and 45% roughage in the complete fattening diet, and 10, 50 and 75% moisture content of the diets. Depot fats collected post-slaughter from kidney, pelvic, ruminal, cod and trim fats in the carcass (mostly subcutaneous and some intermuscular) were weighed and analysed for their fatty acid composition.

Increasing the quantity of roughage in the diet (from 25 to 45%) significantly decreased ruminal fat deposition. Moistening the feed significantly increased the deposition of kidney, pelvic and cod fat, and significantly reduced the deposition of fat trim in the carcass. The content of unsaturated triglyceride fatty acids was significantly greater in calves fed on the 25% roughage diet. Calves fed on the soaked diets had significantly higher contents of unsaturated fatty acids than the controls.

The content of unsaturated acids was greater in cod fat and carcass trim than in kidney, pelvic or ruminal fat.

Hydrogenationin vitroof fatty acids by ruminal micro-organisms decreased with increasing level of moisture in the diet.

It is suggested that the increased unsaturated fatty acid content of the depot fats of animals fed on soaked diets might be due to a reduction in the hydrogenation of dietary lipid by rumen micro-organisms.
A note on the effect of changes in daylength on the seasonal wool growth cycle in Soay sheep
Authors: Ryder M. L. , Lincoln G. A.
Published: September 2010

Seven Soay rams were subjected to a short daylength from the middle of August until the end of October, and this hastened the onset of winter follicle inactivity which normally begins at the end of September. A reversion to long days until the middle of January slowed down the process, and in six animals the usual spring moult was inhibited.
Influence of dietary lysine content on energy utilization in pre-ruminant lambs
Authors: Colebrook W. F. , Black J. L.
Published: September 2010

Male crossbred lambs weighing 10 kg were given, by continuous abomasal infusion, one of a series of diets, equal in energy and nitrogen contents, which provided from 0·887 to 14·863 g lysine per 16 g nitrogen. Gross energy intake was l·38MJ/kg0·75 per day. Oxygen consumption and carbon dioxide production were measured using an open-circuit respirometer when the lambs weighed 12·5 kg. Neither heat production, as calculated from respiratory gas exchange and urinary nitrogen excretion, nor the gross efficiency of utilization of metabolizable energy were affected by the lysine content of the diets.
A trial to evaluate the Milk Marketing Board beef shape assessment scheme for Friesian/Holstein sires
Authors: Cook K. N. , Newton Jennifer M.
Published: September 2010

The Milk Marketing Board beef shape (BS) score for a sire is derived from the beef conformation assessments made during the routine inspection of his first lactation daughters in the Dairy Progeny Testing Scheme. The trial compared the scores for seven Friesian/Holstein sires with the beef characteristics of their steer progeny. Two groups of cattle, 189 in total, all out of Friesian dams, were used in the trial. The dams were assessed for BS. The cattle were reared on a standard grass/cereal system designed to achieve an overall target live-weight gain of 0·85 kg/day and slaughtered at 530 kg live weight. An assessment of BS was made at seven points during the lifetime of each animal. Carcass classification and assessment together with dissection of the shin joint was undertaken by the Meat and Livestock Commission. In addition to this, 40 carcasses representing high and low BS scores were taken for full dissection of the left side.

The BS score of the dam had no significant effect on the score of the calf at any point during its life. The relationship between the sire BS score and the calf score did not become significant until the calf was 12 months old (P < 0·01) and was still significant immediately prior to the slaughter of the calf (P < 0·05). Carcass conformation scores showed highly significant progeny group differences (P < 0·001). The regression of the sire progeny group means, corrected for estimated proportion of subcutaneous fat, on the sire BS scores was significant (P < 0·001). The carcasses in the high BS score group had a significantly greater weight of lean than those in the low BS score group.
The effect of level of feeding on the response of lactating ewes to dietary supplements of fish meal
Authors: Gonzalez J. S. , Robinson J. J. , McHattie I.
Published: September 2010

Thirty-six individually-penned ewes (mean live weight 69 kg), each suckling two lambs, were given one of three diets containing either 128 (low), 155 (medium) or 186 (high) g crude protein (CP) per kg dry matter. All diets contained (g/kg), milled hay, 570; molasses, 95; and a barley/fish meal concentrate, 330. The three protein concentrations were achieved by adjusting the proportions of barley and fish meal in the concentrate. Each diet was given at daily metabolizable energy (ME) intakes of 19, 23 and 27 MJ. Mean daily yields of milk in weeks 3 to 8 of lactation for ewes given the diet with the low concentration of crude protein increased from 2·32 kg at 19 MJ ME to 2·53 kg at 27 MJ. Corresponding values for the medium concentration of CP were 2·49 and 2·67 kg and for the high concentration 2·52 and 3·09 kg (P < 0·05 for differences between ME intakes and differences between dietary protein concentrations). For milk composition, interactions between the concentration of dietary protein and level of ME intake were not statistically significant but the main treatment effects were significant, with the protein concentration in milk increasing from 49·6 g/kg for ewes given the low concentration of dietary protein to 54·1 g/kg for those given the high (P < 0·001). Corresponding values for protein concentration in milk for the lowest and highest energy intake were 51·2 and 53·4 g/kg (P < 0·05). Losses of tissue protein were variable but decreased from 26 g/day for ewes given the low-protein diet to 8 g/day for those given the high. In discussing the responses in milk yield to dietary protein and ME intake attention is drawn to the modifying influence of the energy contributed from body tissue.
Effect of winter nutrition of young farmed red deer on their subsequent growth at pasture
Authors: Adam Clare L. , Moir Carol E.
Published: September 2010

Housed male (stags) and female (hinds) red deer, initial live weight 43·2 and 38·3 kg respectively, were given ad libitum (1) ammonia-treated straw, (2) a barley and fish meal concentrate, and hay, or (3) potatoes and hay, from 7 to 11 months of age. Dry matter (DM) intakes were low for all deer and some live-weight loss was experienced for the first 6 weeks in January/February. Thereafter DM intakes increased, and deer given the concentrate diet showed higher live-weight gain (P < 0·001) than those given potatoes and hay (273 and 162 g/day, respectively) whereas deer receiving the treated straw continued to lose weight (-18 g/day) (P < 0·001).

From 11 to 16 months of age at grass, deer previously given treated straw grew significantly faster (P < 0·001) than those previously overwintered on concentrate or potato diets (215, 156 and 170 g/day, respectively). Final live weights for animals given straw, concentrates and potatoes in the preceding winter were, respectively, 71·6, 92·6 and 80·8 kg (stags) and 63·0, 71·9 and 68·5 kg (hinds).

The dietary treatments imposed in the previous winter had no lasting effects on the carcass composition of stags slaughtered at 16 months, and the practical implications of the different growth patterns are discussed.
Bacon yield from fasted pigs
Authors: Warriss P. D. , Down N. F.
Published: September 2010

Commercial crossbred pigs weighing about 80 kg and comprising equal numbers of females (gilts) and castrated males (castrates) were killed at a bacon factory 4 h (controls), 24 h or 48 h after food withdrawal. The carcasses from pigs fasted 24 h were on average 1·4 kg lighter, and those from pigs fasted 48 h, 2·9 kg lighter, than those of the control group. Fasting also reduced liver weight by about 0·3 kg but had no significant effect on backfat thickness or mean initial or ultimate pH in the muscles. Carcasses were cured into bacon by the Wiltshire process. Those from pigs fasted longer gained less weight after pumping with brine but also lost less weight during brine immersion and maturation. The overall yield of bacon, in relation to carcass weight, was therefore not affected by fasting. Consequently, the reduced carcass weight in the fasted pigs was carried through almost unchanged to the final yield of matured bacon. This was proportionately reduced by 0·019 in the pigs fasted 24 h and 0·043 in those fasted 48 h when compared with the control group.

There was thus no evidence of any material reduction of yield differences during curing which could be caused by equilibriation of water in the carcass tissues with that in the curing brine. The implication is that losses in carcass weight in fasted pigs cannot be attributed simply to dehydration. Cured sides from fasted pigs tended to have proportionately slightly less weight in the ham and middle and more in the shoulder, and bacon from the pigs fasted 48 h was marginally less salty.
Systems of concentrate allocation for dairy cattle 1. A comparison of three patterns of allocation for autumn-calving cows and heifers offered grass silage ad libitum
Authors: Taylor W. , Leaver J. D.
Published: September 2010

High quality grass silage (10·5 MJ metabolizable energy per kg dry matter (DM)) was offered ad libitum to three groups of autumn-calving dairy cattle, each group containing eight cows and eight heifers. In a 20-week period commencing at week 3 post partum each group received, on average, 1260 kg fresh weight of a concentrate containing 180 g crude protein per kg. Animals in treatment F each received a flat-rate of 9 kg concentrates per day throughout. In treatment D, a declining rate of 11, 10, 9, 8 and 7 kg/day was given in successive 4-week periods. Animals in treatment Y were each offered a fixed rate of concentrates (range 7 to 12 kg/day) based on their milk yield at 2 weeks post partum with a mean intake of 9 kg/day for the group. For treatments F, D and Y respectively, the mean daily milk yields were, 26·2, 26·7 and 26·9 kg for cows, and 19·5, 19·1 and 18·8 kg for heifers; mean live-weight gains were, 0·28, 0·30 and 0·22 kg/day for cows, and 0·41, 0·54 and 0·38 kg/day for heifers; and intakes of silage were, 10·1, 10·6 and 10·7 kg DM per day for cows, and 7·8, 7·7 and 7·3 kg DM per day for heifers. The differences between treatments were not significant but there were significant differences between cows and heifers. No significant differences were found between treatments in milk composition although heifers produced milk with significantly higher milk protein concentration (P < 0·05) and significantly greater milk lactose concentration (P < 0·01) than did cows. During the residual period (4 weeks indoors and 16 weeks grazing) all animals were treated as a single group and there were no significant differences in performance. The 305-day milk yields were not significantly different between treatments and averaged 6587 kg for cows, and 5124 kg for heifers.
Systems of concentrate allocation for dairy cattle 2. A comparison of two patterns of allocation for autumn-calving cows offered two qualities of grass silage ad libitum
Authors: Taylor W. , Leaver J. D.
Published: September 2010

In a 25-week experiment beginning at week 3 post partum, grass silages of 10·5 (H) and 8·9 (L) MJ metabolizable energy per kg dry matter (DM) were offered ad libitum to two groups of 24 autumn-calving dairy cows. Within each silage-quality group, two patterns of concentrate allocation were compared, a flat-rate (F) and a variable rate (V). All four treatment groups, HF, HV, LF and LV, received on average 1575 kg fresh weight per cow of a concentrate containing 170 g crude protein per kg during the 25 weeks. The cows on treatment F were all individually given 9 kg concentrate per day throughout. Individuals on the V treatments received different levels of concentrate, based initially on their 14-day milk yield and then reduced by 1 kg/day at 10, 15 and 20 weeks. For treatments HF, HV, LF and LV respectively, mean adjusted daily milk yields were, 24·4, 24·1, 21·6 and 22·1 kg; intakes of silage DM, 9·1, 8·7, 7·6 and 7·6 kg/day, and live-weight gains, 0·39, 0·31, 0·28 and 0·22 kg/day. The effects of silage quality were significant in each case, but the effects of pattern of concentrate allocation were not. Cows given the H silage produced milk with significantly greater lactose and solids-not-fat concentrations. During the residual period (2 weeks indoors and 14 weeks grazing) no significant differences in milk yield were observed. The 305-day yields of 6215, 6096, 5786 and 5824 kg for treatments HF, HV, LF and LV respectively, reflected the differences obtained during the indoor feeding period.
The composition and energy content of empty body-weight change in mature cattle
Authors: Wright I. A. , Russel A. J. F.
Published: September 2010

Body-composition data from 73 non-pregnant, non-lactating cows of five genotypes were used to calculate the composition of empty body-weight change in mature cattle. The composition of empty body-weight change was shown to be dependent on empty body weight, containing more fat and less water, protein and ash at higher empty body weights. There were no differences between the genotypes. Between 300 and 600 kg empty body weight the protein concentration in empty body-weight change ranged from 125 to 40 g/kg, whilst application of standard energy values for fat and protein gave equivalent figures for body energy of 22·5 to 32·7 MJ/kg.
The growth of Clun and Southdown sheep: body composition and the partitioning of total body fat
Authors: Butler-Hogg B. W.
Published: September 2010

The growth of Southdown and Clun lambs was studied over the period birth to 415 days of age.

At birth, 50, 100, 150 and 200 days of age five lambs of each breed, and at 415 days three lambs of each breed, were slaughtered and their body composition determined by dissection.

The relative growth of lean, bone and total body fat was not influenced by breed. At each age both Cluns and Southdowns had similar proportions of total body fat, and were considered to be at the same stage of maturity.

There was a breed difference in fat partitioning, with the Clun depositing proportionately more of its total body fat intra-abdominally, compared with the Southdown. However, there was no significant effect of breed on the growth of individual fat depots relative to total fat. From earliest to latest the order of maturity was pericardial, intermuscular, perirenal-retroperitoneal, mesenteric, subcutaneous and lastly, omental fat.
Asymptotic rates of response from index selection
Authors: Wray Naomi R. , Hill W. G.
Published: September 2010

The reduction in additive genetic variance due to selection is investigated when index selection using family records is practised. A population of infinite size with no accumulation of inbreeding, an infinitesimal model and discrete generations are assumed. After several generations of selection, the additive genetic variance and the rate of response to selection reach an asymptote. A prediction of the asymptotic rate of response is considered to be more appropriate for comparing response from alternative breeding programmes and for comparing predicted and realized response than the response following the first generation of selection that is classically used. Algorithms to calculate asymptotic response rate are presented for selection based on indices which include some or all of the records of an individual, its full- and half-sibs and its parental estimated breeding values. An index using all this information is used to predict response when selection is based on breeding values estimated by using a Best Linear Unbiased Prediction (BLUP) animal model, and predictions agree well with simulation results. The predictions are extended to multiple trait selection.

Asymptotic responses are compared with one-generation responses for a variety of alternative breeding schemes differing in population structure, selection intensity and heritability of the trait. Asymptotic responses can be up to one-quarter less than one-generation responses, the difference increasing with selection intensity and accuracy of the index. Between family variance is reduced considerably by selection, perhaps to less than half its original value, so selection indices which do not account for this tend to place too much emphasis on family information. Asymptotic rates of response to selection, using indices including family information for traits not measurable on the individuals available for selection, such as sex limited or post-slaughter traits, are found to be as much as two-fifths less than their expected one-generation responses. Despite this, the ranking of the breeding schemes is not greatly altered when compared by one-generation rather than asymptotic responses, so the one-generation prediction is usually likely to be adequate for determining optimum breeding structure.