bluuebunny/crossref_metadata_2025 huggingface dataset:
The partition of body fat in British Friesian and Jersey steers
Authors: Butler-Hogg B. W. , Wood J. D.
Published: September 2010

Ninety-two British Friesians and 62 Jersey castrated male cattle were slaughtered serially in five age groups at 13, 89, 170, 339 and 507 days, and dissected fully into lean, bone, intermuscular fat, subcutaneous fat, perirenal-retroperitoneal fat (kidney knob and channel fat), omental fat and mesenteric fat. The aim was to investigate the partition of body fat in these dairy breeds and the role of the partition of fat in determining carcass value.

Relative to live weight, Friesians had more lean, subcutaneous fat and carcass fat (subcutaneous and intermuscular) at most ages, and Jerseys had more kidney knob and channel fat, and intra-abdominal fat. Friesians had a higher killing-out proportion and lean:bone ratio, and thicker subcutaneous fat.

The order of increasing relative growth of fat depots with total body fat as the independent variable was, for Friesians: intermuscular < mesenteric < kidney knob and channel fat < subcutaneous < omental. In Jerseys the order was: intermuscular < mesenteric < subcutaneous < kidney knob and channel fat < omental. There were only small breed differences in the distribution of subcutaneous fat between eight regions. t I is suggested that, between breeds, there is a physiological link between the capacity for milk-fat production and the partition of fat within the body, with relatively high milk-fat producers depositing proportionately more fat intra-abdominally.

Since the timing of slaughter is often determined by level of external finish in beef production, the breed difference in the partition of fat, which caused Jerseys to have a higher proportion of kidney knob and channel fat, and intermuscular fat, at the same proportion of subcutaneous fat, would reduce carcass value in Jerseys compared with Friesians.
Carcass and meat quality of ram and ewe lambs
Authors: Butler-Hogg B. W. , Francombe M. A. , Dransfield E.
Published: September 2010

Carcass composition and quality and eating quality of the m. longissimus dorsi (LD) were compared in 15 entire male (ram) and 15 female (ewe) pure bred Dorset Down lambs (carcass weight range 12 to 23 kg).

Rams grew 28 g/day faster than ewes, taking on average 2 weeks less to achieve 35 kg live weight. At the mean carcass weight of 16-8 kg, ram carcasses contained more lean (42 g/kg carcass weight) and bone (19 g/kg) and less fat (subcutaneous, 33 g/kg; intermuscular, 28 g/kg; perirenal-retroperitoneal, 14 g/kg) than ewe carcasses.

At the same level of fat cover in the commercially prepared side, ewe carcasses required more trimming of subcutaneous fat than rams. However, there was more intermuscular fat (which is not removed by conventional cutting) in the ewes; consequently their saleable meat contained 51 g/kg more fat and 37 g/kg less lean than that from rams.

The roast LD was invariably tender and the eating quality of LD from rams was as desirable as that from ewes, while overall eating quality compared favourably with that of animals studied previously. There was no evidence of an undesirable sexual odour or flavour in ram meat.

With early maturing breeds, which can be finished off grass, non-castration of entire males offers the opportunity of improving the efficiency of lean meat production whilst retaining good carcass and eating quality.
The effects of long-term administration of bovine growth hormone on the lactational performance of identical-twin dairy cows
Authors: Peel C. J. , Sandles L. D. , Quelch Kaylene J. , Herington A. C.
Published: September 2010

The effect of chronic administration of bovine growth hormone (GH) on milk production, food intake and live-weight change was evaluated in five sets of monozygotic twin cows on pasture. Purified bovine pituitary GH (specific activity, 0·78 IU/mg) was administered by daily subcutaneous injections (39 IU/day) for a period of 22 weeks (weeks 5 to 26 of lactation). GH treatment resulted in significantly higher yields of milk (23·3 kg/day), fat (0·97 kg/day), protein (0·74 kg/day) and lactose (115 kg/day) compared with the control group (19·8 kg/day, 0·79 kg/day, 0·63 kg/day, 0·99 kg/day). Milk composition did not differ between treatment groups. There was no difference in the intake of cut grass in week 8 but the voluntary intake of the GH group had increased by week 22 (controls, 15·4 kg dry matter (DM) per day and GH group, 17·5 kg DM per day). There were no differences in the rate of live-weight change for the two groups. Serum somatomedin concentrations were significantly elevated in the GH group on weeks 20 to 22 of treatment (0·043 v. 0·135 U/ml). This experiment indicates that cows chronically treated with GH were able to adjust their food intake upwards to sustain a substantial increase in milk production on a diet composed solely of grass.
Milk production in the Latin-American Milking Criollo and its crosses with the Jersey
Authors: de Alba J. , Kennedy B. W.
Published: September 2010

An analysis was conducted on milk production data collected from 1954 to 1981 at Turrialba, Costa Rica. The local conditions are humid and tropical without a sharply defined dry season. The data included purebred Central American Milking Criollos, Jerseys, their reciprocal F, crosses and backcrosses. Two data sets were created: one with minimum restrictions intended to include production data from all calvings, and another data set intended to include only lactations with normal let-down without the presence of the calf. Data were analysed by maximum likelihood according to a model that included the fixed effects of year of calving, parity of lactation, breed or cross and the regression on year of birth of the sire's first daughter and random effects of sire, cow and error. Breed or cross differences were significant for milk yield, fat-corrected milk (FCM) yield and lactation length but were not significant for fat concentration.

F1 crosses were superior to both parental breeds for milk and FCM yields for both data sets; there were no significant reciprocal effects. The ¾ Criollo backcross had significantly lower milk and FCM yields and shorter lactations than did the F1 or ¾ Jersey. These results suggest that breeding programmes for this type of environment should backcross F1's to Jersey sires and use criss-crossing from then on. The proportion of heterosis for milk, FCM, butterfat concentration and lactation length was 0·26, 0·28 0·02 and 0·15 for minimum-restriction lactations and 0·21, 0·22, 0·01 and 0·09 for normal lactations. Heritabilities for milk, FCM, fat concentration and length of lactation were 0·44, 0·42, 0·28 and 0·41 for minimum restriction lactations and 0·28, 0·27, 0·35 and 0·08 for normal lactations. The relatively higher values for minimum-restriction records suggest a strong genetic effect on ease or difficulty of milk let-down.
Growth and carcass composition of pre-pubertal dairy heifers treated with bovine growth hormone
Authors: Sandles L. D. , Peel C. J.
Published: September 2010

The effects of long-term administration of exogenous growth hormone (GH) on growth and carcass composition of pasture-fed, pre-pubertal dairy heifers were examined. Purified bovine GH (specific activity, 0·78 i.u. per mg) was administered daily for 21 weeks (0·6 mg GH per kg M0·75) to one member of each of 12 sets of twins. GH administration resulted in a significantly higher growth rate (0·58 kg/ day) compared with the control group (0·54 kg/day) and produced a heavier carcass (75·6 kg v. 69·5 kg). However, this production gain did not persist when GH treatment ceased. Plasma metabolite concentrations and carcass composition were not affected by GH treatment. GH tended to increase slightly the voluntary intake of freshly cut herbage dry matter (3·5 kg/day v. 3·7 kg/day; P < 0·05), but had no effect on food conversion efficiency. Serum somatomedin levels were not significantly increased by GH during week 13 of treatment. This experiment indicates that pre-pubertal heifers chronically treated with GH will increase their food intake to sustain an increased rate of growth. However, the production gains made over the treatment period were transient and within 5 weeks of the cessation of GH treatment there was no difference in the live weight of the two groups.
The milk yield and milk composition of the Greek indigenous goat (Capra prisca) as influenced by duration of suckling period
Authors: Zygoyiannis D.
Published: September 2010

Two groups, A and B, each consisting of 12 Greek indigenous goats suckling single kids were traditionally fed during a 36-week lactation period. During the suckling period (6 and 12 weeks for the groups A and B, respectively) milk production was estimated at 7-day intervals. During the milking period (30 and 24 weeks for the groups A and B, respectively) the goats were hand milked twice daily and their milk production was measured at intervals of 4 weeks. Milk samples were analysed for fat, protein, lactose, ash and dry matter concentration. Solids-not-fat and energy concentration were calculated. During lactation the goats were weighed weekly up to week 12 and monthly thereafter and body condition score was assessed at each weighing.

Goats with a 6-week suckling period produced significantly less milk throughout lactation but significantly more marketable milk than those with a 12-week suckling period. Yield peaked at the 6th and 10th weeks of lactation respectively, then declined rapidly and tailed off gradually from weeks 7 and 16 respectively. Milk composition was affected only occasionally by the duration of the suckling period. Thus, fat concentration was higher for the group with the 6-week suckling period between weeks 7 and 16, whilst protein was higher between weeks 8 and 12. Lactose concentration was lower for the same group between weeks 7 and 11, whilst ash concentration was similar in both groups. Live weight and body condition of the goats throughout lactation showed similar changes in both treatment groups.
A note on the influence of a Göttingen miniature boar on puberty attainment in Large White gilts
Authors: Booth W. D.
Published: September 2010

The initial work of Brooks and Cole (1970), which showed that a mature boar advances the onset of puberty in gilts, has become known as the ‘boar effect’, and this phenomenon has now been confirmed in numerous studies as reviewed by Hughes (1982), and Kirkwood and Hughes (1982).
Optimum selection procedures in animal breeding
Authors: Smith Charles
Published: September 2010

A simple expression relating the standardized selection differential (i) to the intensity of selection (p) is given by

i≏0·8+0·41 ln (R−1)

where R equals 1/p. This linear expression may allow simpler solutions to some optimization problems in selection than does the conventional formula for selection differential on truncation of the normal curve.

Using the expression, formulae for the maximum immediate response and optimum selection intensity in mass selection have been developed, taking account of the loss in performance through inbreeding. These formulae were used to study the effect on response of the total number of animals tested. The maximum response over a specified period of time, allowing for the loss in genetic variance from inbreeding, has also been considered. The optimum intensity of selection may then be well below that necessary for the maximum immediate response.
The rumen pathology of intensively managed beef cattle
Authors: Rowland A. C. , Wieser M. F. , Preston T. R.
Published: September 2010

Histological examination of the rumen wall in intensively managed beef cattle confirmed the superficial nature of many of the lesions present and failed to reveal evidence of secondary bacterial infection. Of the lesions described, only intra-mucosal abscesses and their subsequent erosions proved to be significantly related to the occurrence of hyperkeratosis of the rumen mucosa. The remaining lesions, vacuolation of the stratum granulosum, acute microscopic ulceration, congestion of the submucosa and the presence of leucocyte aggregations in the submucosa, were all independent of this hyperkeratosis.
The control of voluntary food intake in ruminants
Authors: Owen J. B. , Davies D. A. R. , Ridgman W. J.
Published: September 2010

An experiment to test the effect on the voluntary food intake of lambs of giving diets containing 0, 20, 40 and 60% of either coarse or finely ground oat husks, in either a loose or pelleted form, is described and the results discussed. The results showed that voluntary intake was uniformly depressed with increased dilution of the diet with oat husks when the oat husks were coarse and the diet given loose. However, when the oat husks were finely ground and when the diet was pelleted the response to dilution was much modified and in the case of older, heavier lambs intake initially increased with dilution. It is concluded that ruminants may sometimes be able to respond to increased diet dilution so as to maintain their maximum digestible-energy intake but that the attempt is often thwarted to varying degrees according to the physical form of the food. An hypothesis is suggested for the pattern of response in food intake to be expected according to the type of food given.
A note on the effect of amino acid or urea supplements to barley diets for the finishing pig
Authors: Hintz H. F. , Pond W. G. , Visek W. J.
Published: September 2010

In trials 1 and 2, supplements of urea and cottonseed meal increased the protein content of the basal diets from 12·2 to 14·0–14·6%, but had no significant effects on growth rate or carcass characteristics. In trial 3 the effect of cottonseed meal on growth rate was almost significant but urea had less effect. In trial 4, the basal diet contained 11·0% protein; soya bean meal increased this to 13·1% and had an almost significant effect on growth rate. Lysine and lysine + urea had no effect.
Studies on the nutrition of ruminants: 5. The effect of diets containing up to 70% ground barley straw on the live-weight gain and carcass composition of yearling Friesian cattle
Authors: Swan H. , Lamming G. E.
Published: September 2010

1. Three groups, each of eight steers, were fed on pelleted diets containing 30, 50 or 70% ground barley straw, maize and soya bean meal. On an air-dry basis the diets contained 12% crude protein.

2. Daily live-weight gain was 1·29, 1·19 and 1·02 kg/day for the 30, 50 and 70% straw diets respectively, and was negatively related to the percentage of crude fibre in the dry matter (r = −0·61, P < 0·05).

3. The apparent digestibility of dry matter, determined in sheep at the maintenance level of feeding was negatively related to percentage crude fibre in the dry matter (r = −0·91, P < 0·001).

4. All animals were killed at approximately the same live weight, which was reached on average in 140,153 and 163 days by the 30, 50 and 70% groups, respectively.

5. The differences in mean carcass weight between treatments were significant (P < 0·05). Killing-out percentage was significantly reduced (P < 0·05) as the proportion of ground barley straw in the diet was increased from 30 to 70%.

6. The proportion of straw in the diet had no direct effect on the composition of carcass gain.

7. The results are discussed in relation to the intake of digestible energy.
Photoperiodism in the ewe: 1. The effect of long supplemented daylengths on the breeding activity of pregnant and non-pregnant Teeswater-Clun ewes
Authors: Ducker M. J. , Thwaites C. J. , Bowman J. C.
Published: September 2010

Daylengths of 13 or 20 hr were applied to six groups of nine ewes during the 2nd to 8th, 8th to 14th and 14th to 20th week of pregnancy. Two groups of nine non-pregnant ewes received a constant 13- or 20-hr daylength during the above experimental period. A group of 10 non-pregnant ewes which initially received a 20-hr daylength were subjected to a 13-hr daylength in the last 14 to 20 weeks of the experimental period. After parturition (26 March) all the ewes received increasing natural daylength.

The mean number of days from the onset of the experimental light treatments (17 November) to the cessation of oestrous activity did not vary significantly between the three non-pregnant groups of ewes and was on average 89 days.

Only two of the 82 ewes, both non-pregnant, exhibited oestrus prior to the longest day (22 June). The various light treatments did not significantly affect the mean dates of occurrence of the natural breeding season of the groups of ewes.
A note on a Urea feeding experiment with sheep in Iran
Authors: Sarif-Sarban M. , Menke K. H.
Published: September 2010

Four groups of 50 sheep were given rations containing barley, dried beet-pulp, wet beet-pulp silage, lucerne hay and straw, with A, no protein supplement; B, 1·6% urea; C, 21% Rumevite (supplying 1·3% urea); and D, 15% cottonseed cake. Average daily gains in body weight were 143, 187, 190 and 189 g for groups A to D respectively. Undernourishment and infection with endoparasites did not affect adaptation to urea.
Nutrition of the early-weaned calf. XI. Intake of diets differing in energy concentration
Authors: Kay M. , MacLeod N. A. , McLaren Margaret
Published: September 2010

1. A growth and digestibility trial was carried out with 27 British Friesian calves given diets having either 3·1, 2·8 or 2·4 Meal metabolizable energy per kg dry matter and either the same concentration of protein or the same protein-to-energy ratio.

2. Daily dry-matter intake and rate of gain in live weight increased significantly as the energy concentration of the diet was reduced. There were no significant differences in digestible-energy intake between calves given the different diets, although the trend was the same as for dry-matter intake.

3. Both dry-matter digestibility and energy digestibility were lowest for the low-energy diet.
The performance of two breeds given different amounts and sources of protein in a high-molasses diet
Authors: Preston T. R. , Willis M. B. , Elías A.
Published: September 2010

On a fattening diet in which final molasses supplied from 68 to 76% of the metabolizable energy and napier grass some 10%, the treatments in a 2 × 2 × 3 factorial design were breed (Brahman or Brown Swiss × Brahman), source of supplementary protein (fish meal or poultry waste) and protein level (low, medium or high—replacing urea). Mean daily gains to 404 kg live weight were better for the crossbreds (0·89 compared with 0·77 kg), as was conversion rate in terms of Meal ME per kg gain (25·6 compared with 29·5); fish meal improved gains by 44% and conversion rate by 39% as compared with poultry waste when the two supplements were fed at levels designed to equate N intakes from this source. The superiority of the crossbreds was only apparent on the fish meal diets where they averaged 1·19 compared with 0·94 kg/day for the Brahmans. Daily N × 6·25 intakes decreased from 3·8 g/kg live weight on the low level of poultry waste to 2·9 on the high level due to low palatability of this material. On this treatment (poultry waste), daily gain (kg) was significantly related (b = 0·119±0·031; P<0·01) to N×6·25 intake (g) per unit live weight (kg). Commercial half carcass dissection showed the crossbreds to have significantly more edible meat, more bone and less e×cess fat than Brahmans. Protein source had no effect on carcass composition.
Responses in milk yield and composition to the inclusion of ammonium salts of short-chain fatty acids in the drinking water of dairy cows
Authors: Jackson P. , Rook J. A. F.
Published: September 2010

The effect of introducing a solution of fatty acids (consisting mainly of ammonium acetate) into the drinking water of Jersey and Friesian cows on the yield and composition of milk was investigated. In short-term experiments there were small increases in milk yield and in the yield of fat in Jersey cows receiving either a high-roughage or a high-concentrate diet and in Friesian cows receiving a high-concentrate diet. Friesian cows receiving a high-roughage diet gave no response. In a long-term experiment extending over 16 weeks of lactation with Jersey cows receiving a high-concentrate diet, there was no immediate effect on milk yield but a greater persistency and overall the yield of fat was increased by 5·9%.

Inclusion of ammonia salts in the drinking water caused increases in the ammonia contents of rumen liquor and of blood but there was little effect on rumen pH or the volatile fatty acids of rumen liquor.
A note on the variation and heritability of twinning in British Friesian cattle
Authors: Bowman J. C. , Frood I. J. M. , Wood P. D. P.
Published: September 2010

Records of calving, excluding first calving, on 2862 cows, the daughters of 63 bulls used in AI were analysed to estimate the incidence and variation of twinning between bull progeny groups. The mean incidence of twinning was 2·8% and though the incidence increased with later parities the effect of parity was not significant. The incidence for bull progeny groups ranged from 0 to 8·8%. The intraclass correlation between parities for cows within bulls was 0·064±0·018 and a sire half sib group estimate of heritability for twinning, based on a single calving, was 0·43±0·012.
The induction of pregnancy during lactation in the sow: the effects of a treatment imposed at 21 days of lactation
Authors: Crighton D. B.
Published: September 2010

1. Experiments carried out in two herds to examine the effects of a treatment designed to induce oestrus and ovulation during the lactational anoestrus of the sow and to allow the establishment of pregnancy during lactation are described. Two aspects are examined: (a) the effects on the reproductive performance of the sow of repetition of the treatment in successive lactations and (b) the effects of the treatment on the suckled young.

2. The treatment involved the separation of each sow and litter for 12 hr on days 21, 22 and 23 of lactation followed by an injection of 1500 IU pregnant mare serum gonadotrophin (PMSG) at the end of the third period of separation.

3. It is concluded that oestrus and ovulation can be induced with some consistency in the fourth week of lactation, that lactation is not incompatible with the first two to three weeks of pregnancy, and that the establishment of pregnancy during the fourth week of lactation is not detrimental to the growth of the suckled young when supplementary food is provided.
Yield of colostrum and immunoglobulin in cattle at the first milking after parturition
Authors: Kruse V.
Published: September 2010

The experimental animals consisted of 71 heifers or cows of the Black and White Danish breed (SDM), 61 heifers or cows of the Red Danish breed (RDM), and 8 heifers or cows of the Jersey breed. Highly significant differences between breeds were found in yield of colostrum at first milking after calving and in the concentration of immunoglobulin (Ig) in colostrum. The RDM animals had the highest colostrum yield but the lowest Ig %. The total yield of Ig was not significantly different between RDM and SDM. The individual variation in colostrum yield, Ig %, and Ig yield was very marked.

Heifers had a lower colostrum yield and Ig yield than cows in second and later lactations. For SDM the Ig % was not dependent on the lactation number. In contrast the older RDM cows had a significantly higher Ig % in colostrum than the younger cows. No effect of season of the year was found on colostrum yield, Ig %, and Ig yield. An increase of the interval between calving and the first milking caused a very significant drop in colostrum Ig %. Loss of colostrum from the udder before milking increased the probability of getting colostrum with low Ig %. The repeatability in Ig % at successive calvings was found to be high.
Computer simulation of reciprocal recurrent selection with overdominant gene action
Authors: Arthur J. A. , Abplanalp Hans
Published: September 2010

Previous studies have shown that reciprocal recurrent selection (RRS) would be ineffective in the early cycles of selection if over-dominant loci were at equilibrium gene frequencies in both selected populations. It is shown in the present study that response to RRS may be reduced by this unstable equilibrium even when gene frequencies are as much as 30 % removed from the theoretical equilibrium frequency. Reducing one population to a bottleneck of two individuals for one generation or more before initiating RRS (RRSB) was very effective in overcoming the unstable equilibrium. RRS with recurrent inbreeding, then outcrossing in both populations each cycle of selection (RRSC) was not effective in overcoming the unstable equilibrium, but yielded greater response per cycle after selection response began. The effectiveness of RRSC was inversely proportional to the heritability of the trait. Use of these modifications to increase the effectiveness of RRS in poultry breeding is discussed.
The development of solid food intake in calves. 1. The effect of previous experience of solid food, and the physical form of the diet, on the development of food intake after weaning
Authors: Hodgson J.
Published: September 2010

1. British Friesian male calves were offered reconstituted milk substitute four times a day in steadily increasing quantities, so that the amount offered exceeded appetite after 14 days. They were given one of three dried herbage diets (pellets P1 and P2, and untreated material H2 made from the same crop as P2) to appetite, either from the start of the experiment (Treatment A) or from the start of weaning (Treatment W) 21 days after arrival. The experiment was terminated six weeks after the calves were weaned.

2. Grinding and pelleting (P2 v. H2) markedly reduced the in vivo digestibility of the diet, and the time of retention in the alimentary tract, increased the voluntary dry-matter intake by 50% and live-weight gain of the calves by 100%. The intakes of the two pelleted diets were similar.

3. The intake of diet H2 after weaning was greater in calves which had experience of the diet before weaning than in those which did not, but the intake of the pelleted diets was not affected by previous experience of solid food. The time required to eat unit weight of dry matter was four times as long for diet H2 as for the pelleted diets, and there were similar differences between diets in ruminating time. It is suggested that the development of solid food intake is influenced by the ease with which the diet can be eaten.

4. The initial increase in solid food intake after weaning was related to an increase in the times spent eating and ruminating, but later increases in food intake were achieved with no further increases in eating or ruminating time.
Investment appraisal for national breeding programmes
Authors: Hill W. G.
Published: September 2010

The discounted cash flow procedure of management accounting is used to evaluate national breeding programmes. Alternative methods of improvement of meat production from cattle born in the dairy herd are taken as examples. These schemes utilize selection for beef characters either in the dairy breed itself or within a beef breed, maintained in a small herd and used as a source of bulls for crossing by AI. In each case young bulls are selected for growth rate in a performance test, which precedes the progeny test for milk production in the dairy breed.

Greater rates of genetic progress and monetary returns are predicted from improvement of the beef breed, but both schemes are expected to yield a return on investment of over 15%. The net returns from the programme in the beef breed are influenced less by changes in assumptions.

Approximate, but simple, methods of computing the discounted returns are described.
The voluntary intake of roughages by pregnant and by lactating dairy cows
Authors: Marsh R. , Curran M. K. , Campling R. C.
Published: September 2010

1. Effects of late pregnancy and early lactation on the voluntary intake of dried grass (Expt 1) and a poor quality seeds hay (Expt 2) by dairy cows are described. Each cow received a constant daily allocation of concentrates throughout late pregnancy. After calving half the cows received an 80% increase in concentrates, and the remainder continued to receive their pre-partum allowance.

2. Mean daily intakes of dried grass were higher than those of poor quality seeds hay. Intake of dried grass in week 2 of lactation was significantly correlated with the live weight of the cows, but a non-significant correlation was observed when seeds hay was offered.

3. During late pregnancy mean daily intakes of both roughages were approximately constant until the week immediately before par turition, when a significant decline occurred.

4. After calving mean daily intakes of both roughages increased throughout the first six weeks of lactation by 20–30% of the intake at week 1 post partum.

5. The 80% increase in daily concentrate allocation in early lactation caused a significant decline of 0·55 kg dried grass dry-matter intake per kg concentrate dry matter; the decline of 0·17 kg poor quality hay dry matter per kg concentrate dry matter was not significant.
Crossbreeding beef cattle in Western Uganda. 2. Environmental influences on body weight
Authors: Sacker G. D. , Trail J. C. M. , Fisher I. L.
Published: September 2010

The nine possible breed types resulting from the use of Angus, Boran and Red Poll bulls on Ankole, Boran and local Zebu cows were represented in the experiment. Sex, period of birth and year of birth had significant effects, at practically all ages, on body weights of calves measured at three-monthly intervals from birth to two years. Age of dam had a significant effect on calf weight at birth but not thereafter. Previous parous state of dam had only few apparently significant effects on calf weights at different ages. It appeared that beneficial effects of a good pre-weaning maternal environment might be retained, as there was no strong evidence of post-weaning compensatory growth for pre-weaning maternal effects due to age and previous parous state of dam.
The nutritive value of separated milk for pigs. III. A note on the effects of supplementary lysine and methionine on performance to 55 kg live weight
Authors: Chamberlain A. G. , Cooke B. C.
Published: September 2010

Attempts were made to improve the nutritive value of diets based on separated milk and barley by adding free lysine and methionine. Feeding trial and nitrogen metabolism studies showed small beneficial responses to lysine, but not to methionine; the effects however were not statistically significant.
Moist barley preserved with acid in the diet of the growing pig
Authors: Perez-Aleman S. , Dempster D. G. , English P. R. , Topps J. H.
Published: September 2010

The feeding value of moist barley (approximately 27% moisture) which had been treated with 1·3 % of a mixture of formic (70 %) and propionic (30 %) acids was compared with that of dried barley for growing pigs from 23 to 85 kg live weight. Two experiments were undertaken; 96 pigs were fed ad libitum on one of three diets containing dried or acid-treated moist barley and another 48 pigs were individually fed on one of four diets containing dried or acid-treated moist barley in controlled amounts. These amounts were governed by an allowance of dry matter at a certain live weight.

In neither experiment were significant differences found between the treatments in growth rate or efficiency of utilization of food dry matter. Pigs fed ad libitum showed no significant difference in intake of dry matter, but those given the diet containing dried barley had a higher content of fat in their carcass than those on the acid-treated barley. A total of 21 pigs, 16 fed ad libitum and all receiving diets containing acid-treated barley had a discolouration of fat in the carcass.
The influence of environmental temperature and plane of nutrition on heat losses from individual pigs
Authors: Close W. H.
Published: September 2010

1. The total rate of heat loss from individual pigs (20 to 40 kg body weight) was measured over 6-hr periods in a small heat sink calorimeter at 7°, 20° and 30°C, with feeding levels of 34, 39, 45 and 52 g/kg body weight per day.

2. Total heat loss at 7°C was significantly greater than at 20° or 30°C; there was no significant difference in heat loss between temperatures of 20° and 30°C.

3. Heat loss per m2 of body surface was independent of feeding level at 7°C. At 20°C, heat loss on the high feeding level was significantly greater than that on the low level, and at 30°C heat loss on both the low and medium feeding levels was significantly greater than that on the very low level.
A note on dissectable lean, fat and bone of the foreshank as predictors of beef carcass composition
Authors: Epley R. J. , Zobrisky S. E. , Chrystall B. B. , Hutcheson D. P. , Hedrick H. B. , Stringer W. C.
Published: September 2010

Regression equations predicting weight and percentage of both forequarter and total side retail cuts from 126 beef carcasses were calculated. Dissectable shank muscle weight, shank bone weight and shank soft tissue weight, but not shank fat weight, were useful in predicting weight of forequarter and total retail cuts. However, intact shank weight was as valuable as any single dissection component of the shank in predicting weight of both forequarter and total retail cuts. Separable muscle, fat, bone and soft tissue percentages of the shank were not useful in predicting percentage retail cuts of either the forequarter or the entire right side.
Effects of crossbreeding and certain environmental factors on multiple births, wool production and growth in sheep
Authors: Fahmy M. H. , Bernard C. S.
Published: September 2010

Multiple birth percentage and wool production were studied on 338 ewes (907 lambing and 873 shearing records) representing two purebreds, Oxford (O) and Suffolk (S), and four crossbreds, O × S, S × O, Cheviot (C) × O and C × S mated to purebred and crossbred rams during 9 years. Oxford ewes had 24–32% (P<0·01) fewer multiple births than ewes of the other groups, while little difference between S and the crossbreds was observed. The heterosis of the OS and SO groups was 14·6 ± 4·1%. Multiple births tended to increase 0·8% for each kg increase in body weight of the dam (r = 0·13). The repeatability estimate for multiple births was 0·24. Fleece weight was significantly affected by age and by breed group, with OS and SO crosses producing 17% more wool than their parental breeds. The repeatability of fleece weight was estimated at 0·52 ± 0·15. Fleece weight was significantly correlated with multiple birth percentage (0·09) and body weight (0·32).

Suffolk ewes averaged 9·5 kg heavier than O ewes throughout their reproductive life. The two reciprocal crosses were heavier than both parental breeds. Suffolk ewes reached their maximum body weight at 4 years of age while Oxfords continued to gain weight up to 6 years.
Ammonium salts of fatty acids for milk production. 3. The effect of a salt solution containing ammonium acetate on milk yield and composition in Jersey cows fed on a high concentrate diet
Authors: Khalifa H. A. , Prescott J. H. D. , Armstrong D. G.
Published: September 2010

1. The experiment involved four pairs of Jersey cows in a double reversal trial with two treatments.

2. The control and acetate treatments involved iso-caloric concentrate mixtures together with hay. The concentrates and hay were given in constant ratio of 3 : 1 and total feed intake was regulated according to milk yield. Cows on the acetate treatment received a dilute solution of fatty acids (1·7 % w/w) and an all-cereal concentrate mixture; those on the control diet received water and a concentrate containing 10% groundnut meal. The dilute solution of fatty acids provided approximately 31 % of the total digestible crude protein intake as ammonia-N, and 208 g acetate and 34 g propionate per day.

3. The two treatments gave similar dry-matter intakes. The acetate treatment caused a slight and significant depression of milk yield but the fat content of the milk and fat-corrected milk yield were slightly increased by treatment, though not significantly so. The results have been discussed with reference to the end products of digestion in the rumen and role of ammonia-N as a substitute for protein-N.
The roughage requirement of the early-weaned calf
Authors: Kang Hi Shin , Leibholz Jane
Published: September 2010

An experiment was conducted with 50 male Friesian calves between 5 and 11 weeks of age. Milled wheat straw (0·95 cm screen) was included in a pelleted all-concentrate diet at concentrations of 0, 15, 30 or 45 %. The nitrogen content of the diets was maintained by the addition of urea. The diets were given alone or with a chaffed lucerne hay or wheat straw supplement ad libitum. All diets contained 2 % sodium bicarbonate.

The feed intake and weight gains of the calves were increased significantly by the inclusion of 15 % milled wheat straw, but were reduced by 30 or 45 % straw. The supplements of chaffed wheat straw or lucerne hay ad libitum did not influence the performance of the calves. The inclusion of wheat straw in the diets reduced their dry-matter digestibility but the digestibility of acid detergent fibre was maximal with 27 % straw. The digestibility of nitrogen was significantly increased by 15% straw but reduced by further increases in straw.

The inclusion of wheat straw in the diets did not influence the pH of the rumen contents or the concentration of total volatile fatty acids in the rumen. Increasing the level of straw in the diet caused a significant linear increase in the proportion of acetic acid and decreases in butyric, propionic and valeric acids.
A note on the comparison of digestion by New World camels, sheep and ponies
Authors: Hintz H. F. , Schryver H. F. , Halbert M.
Published: September 2010

Digestion trials were conducted with four ponies, two sheep and two New World camels (one llama and one guanaco) given alfalfa pellets and a complete pelleted hay-grain diet. The New World camels were significantly more efficient in the digestion of dry matter, neutral-detergent fibre, acid-detergent fibre and cellulose than the sheep or ponies.
A note on the effect of sudden changes in the composition of the diet of growing pigs
Authors: Livingstone R. M.
Published: September 2010

Two diets, one based on barley and white-fish meal and the other on oats, wheat and meat and bone meal, with similar concentrations of digestible energy, crude protein, lysine and methionine+cystine were used to investigate the effects of sudden changes in the composition of the diet on the performance of pigs growing from 32 kg live weight, over a period of 77 days.

The diets were given separately, alternated weekly with sudden changes from one diet to the other, or as a 1:1 mixture.

Changes in diet per se had insignificant effects on performance.
Moist barley preserved with propionic acid in the diet of the growing pig
Authors: English P. R. , Topps J. H. , Dempster D. G.
Published: September 2010

The feeding value of three forms of acid-treated moist barley, viz. 26 % moisture and either rolled or plate-milled, and 29 % moisture plate-milled, was compared with that of dried hammer-milled barley for growing pigs from 23 to 87 kg live weight. Two feeding experiments were undertaken, one in which individual pigs were given the same amount of dry matter from all the diets, while in the other, groups of pigs were fed ad libitum. Digestibility of the diet was determined in a third experiment.

In both feeding experiments differences between treatments in efficiency of utilization of dry matter in the feed were significant (P<0·05), that for the diet containing dried barley being approximately 5% better than the other three. There were no significant differences between treatments in intake of dry matter, rate of growth and carcass quality of the pigs. However, pigs fed on dried barley apparently grew more rapidly than those given any of the acid-treated moist barleys. Differences in digestibility of the diets were very small and not significant except for crude protein. Differences in digestibility of protein (P<0·05), however, were not consistent with differences in efficiency of conversion of dry matter in the feed.
The possible use of superovulation and embryo transfer in cattle to increase response to selection
Authors: Land R. B. , Hill W. G.
Published: September 2010

The possible use of superovulation and embryo transfer in selection programmes in cattle is investigated theoretically, in terms of both rates of response and inbreeding.

In a selection programme for growth rate, it should be possible to achieve about twice the response of a conventional performance testing programme, so that 400-day weight, for example, could be increased by 16 rather than 9 kg per year.

The improvement of reproductive performance by the use of laparoscopy to measure the natural ovulation rate of animals over several oestrous cycles followed by superovulation of selected animals is investigated. The rate of progress is dependent upon the incidence of twin ovulations in the base population and is unlikely to exceed 0·6% per year unless the initial frequency is 8% or more.
Analyses of some factors which affect the productivity of beef cows and of their calves in a marginal rainfall area of Rhodesia. 1. Factors affecting calving rate
Authors: Richardson F. D. , Oliver J. , Clarke G. P. Y.
Published: September 2010

The productivity of cows grazing on veld was studied over four breeding seasons. Different amounts of concentrates were given to three groups of cows during winter and up to 8 weeks post partum. Half of the cows in each group had their calves weaned early (150 days) and the others at the normal time (240 days). Cows given concentrates produced more calves than those given none but time of weaning had no consistent effect on successful conception rates (as judged by subsequent calving rate).

Probit analyses were used to determine the relationship between seasonal body-weight change in the cow and the probability of successful conception. The estimated percentage body-weight changes from autumn peak to mean body weight at the beginning and end of the mating season, which would be followed by successful conception rates of 50%, 75% and 90%, were −14%, −6% and +1% of autumn body weight, respectively.

The practical implications of these results are discussed.
A note on digestibility in sheep as influenced by level of intake
Authors: Robertson J. B. , Van Soest P. J.
Published: September 2010

Digestibility of dry matter, energy and cell wall was measured in two series of digestibility trials in which sheep were fed on pelleted mixed rations containing either 32·0 or 22·6% cell wall at various levels of intake. There were significant depressions in digestibility of all nutritive components as the level of intake increased. The ration lower in cell wall showed smaller declines in dry matter and energy digestibility but a greater decline in cell wall digestibility. The results indicate that the cell wall fraction of concentrate-supplemented rations for sheep is a primary factor in the decline in digestibility observed with increase in level of intake.
Relations between first and second lactation characters of progeny groups and effects of tandem selection on yield improvement
Authors: Bar-Anan Reuven
Published: September 2010

Correlations and regressions between estimated breeding values for 122 day part-lactation, 1st and 2nd lactation yield (part, 1st, 2nd) were estimated from 106 sire progeny groups, each with at least 60 effective daughters.

The genetic correlations between part, 1st and 2nd kg milk were 1·0 and 0·84 respectively, and the regressions of 1st on part and of 2nd on 1st test were 2·40 and 0·82 kg/kg milk, respectively. Selection by one standard deviation between sires on part-lactation tests would improve 1st lactation yields by an average of 204 kg milk with a standard deviation of 84 kg. Selection on 1st lactation yields by one standard deviation would increase 2nd lactation yields by an average of 183 kg milk with a standard deviation of 156 kg, indicating that some bulls so selected could have below average 2nd lactation yields.

Two sire selection models were simulated differing in the selection criterion; 1 st yield in model 1, and 1 st followed by 2nd yields in model 2. The contribution of proven sires to the rate of genetic improvement in lifetime production was greater from model 2 than from model 1 by about 15% without any additional costs for bull maintenance.
The growth of Ayrshire cattle: an analysis of linear body measurements
Authors: Russell W. S.
Published: September 2010

The growth of 12 linear body measurements in Ayrshire cattle was analysed by least-squares methods. Measurements were taken at 3-monthly intervals up to 48 mo of age. Adjustments were made for month and year of birth and for type of birth (twin-born animals comprised 40% of the data). The state of pregnancy or lactation in heifers was also taken in account. Growth curves were fitted to the mean values at the 16 ages and were found to give a close fit. Residual deviations, though small, did show a systematic pattern. The estimated degree of maturity at birth ranged from about 25% for measures of width to 50% for measures of height, body length being intermediate at 40%.

To a large extent the different body measurements maintained a uniform pattern of maturing and their ranking for earliness of maturity tended to remain constant throughout the growth period. The application of allometry to the measurements is examined and the error introduced by extrapolating an allometric relationship between characters of different maturing rates is illustrated.
Polledness and intersexuality in the Damascus breed of goat
Authors: Hancock John , Louca Avraam
Published: September 2010

Data on 2208 parturitions involving 3594 kids were used to study the inheritance of polledness and its relationship with intersexuality in the Damascus breed of goat.

The percentage of horned kids in the offspring of polled × polled and horned × horned matings was 26·8 and 100·0, respectively. The corresponding value for matings having one parent horned was 50·3%.

There was a consistent excess of males in the sex ratios. Males comprised 53·8, 52·4, 60·2 and 54·0% of the offspring of polled x polled, polled x horned, horned x polled and horned × horned matings respectively. The corresponding proportions for the intersexes were 6·2, 0·3, 0·0 and 0·0%. The incidence of intersexes was not affected by type of birth (single, twin or multiple) or sex of littermates.

It was concluded that the data from the Damascus breed of goat conform with the current theory on the behaviour of the P gene concerning polledness (direct dominant effect) and intersexuality (pleiotropic recessive effect) in the Swiss breeds of goat.
Mating of sows during lactation: Observations from a commercial unit
Authors: Rowlinson P. , Boughton H. G. , Bryant M. J.
Published: September 2010

Observations were made on a commercial herd of female pigs (sows) where a managemental system was employed which enabled sows to be served during lactation. The system involved grouping between 2 and 8 sows together with their litters about 3 weeks post partum. The sows were fed ad libitum from grouping, and the piglets had ready access to creep food. After one day a male pig was introduced to the group. No exogenous hormone therapy was used.

Results from 39 batches, comprising 180 sows, suggested that sows kept under these conditions will exhibit oestrus, and conceive during lactation with a high degree of predictability. Lactational oestrus was shown by all sows and conception to first service was 84·9%. The number of days between grouping and oestrus, and parturition and oestrus, were 11·15 ±0·28 and 35·53 ±0·47 respectively. Litter size and performance did not appear to be adversely affected by the concurrent lactation and pregnancy, either at the present or subsequent parturition. The average farrowing interval of 153 days allowed a performance of 2·35 litters/sow per year, and, with 9·47 piglets weaned/litter, a productivity of 22 piglets/sow per year.