bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemical and dissected composition changes in weaned piglets
Authors: Whittemore C. T. , Taylor H. M. , Henderson R. , Wood J. D. , Brock D. C. 
Published: September 2010

ABSTRACTTwenty-four pigs were weaned at 21 days of age and given restricted feed allowances for the subsequent 8 days. Eight suckled pigs served as control and gained 320 g daily, of which approximately 40 g were lipid and 40 g protein. Pigs were slaughtered at 2-day intervals, physically dissected into non-carcass, carcass fatty tissue and carcass muscle plus bone, and these fractions were then analysed for water, protein and lipid. On average, weaned pigs made small positive body-weight gains. In comparison with suckled pigs, weaned pigs contained more water and less lipid but the same protein, and more non-carcass and less carcass fatty tissue but similar carcass muscle plus bone. Losses of lipid were offset by gains of water and associated with an increase in the percentage water content of carcass fatty tissue. At zero weight gain, pigs lost 43 g carcass fatty tissue, gained 37 g non-carcass, lost 56 g lipid and gained 53 g water, while carcass muscle plus bon e and protein gains were themselves not significantly different from zero. No change in carcass fatty tissue weight was associated with counterbalancing losses of lipid (18 g) and gains of water (15 g) and protein (3g). Lipid catabolism to support anabolism of essential body tissues commenced in the weaned pigs when weight gains fell below 193 g/day; this was about two-thirds of the gains achieved by the suckled control pigs. Plasma free fatty acid concentrations indicated that maximum lipid catabolism to occur on the 2nd day after weaning, and to reduce thereafter as body fat stores were progressively depleted.
A note on the protection provided by the hair coat or fleece of the animal against the thermal effects of simulated rain
Authors: Holmes C. W. 
Published: September 2010

ABSTRACTThe rate of heat transfer from a model animal, covered with one of three animal pelts, was measured when the pelts were dry and when they were exposed to a fine spray of water. Wetting of the pelts increased heat transfer by 192, 114 and 15W/m2 respectively for the hairless skin, the skin with calf's hair coat (5 to 10 mm) and the skin with the lamb's fleece (60 mm). These results demonstrate the considerable protection against the thermal effects of wetting which is provided by animal coats, particularly if these are relatively deep.
Carcass composition of double-muscled cattle
Authors: Johnson E. R. 
Published: September 2010

ABSTRACT1. An anatomical explanation of the observed differences between double-muscled and phenotypically normal cattle was sought by detailed dissection of the sides of six double-muscled Santa Gertrudis steers and six Brangus steers.2. Relative to carcass weight the double-muscled steers had a significantly greater proportion of muscle and a significantly lower proportion of bone and fat than the Brangus steers. Relative to muscle plus bone weight the muscle proportion was greater and the bone proportion lower in the double-muscled steers.3. The musculature of the double-muscled steers exhibited a gradient of hypertrophy: 12 muscles (234g/kg of total muscle weight) were grossly hypertrophied, 56 muscles (565g/kg) were hypertrophied to a lesser degree and 28 muscles (195g/kg) showed either a minor degree of hypertrophy or no hypertrophy.4. The grossly hypertrophied muscles were generally the larger, superficial muscles of the proximal pelvic limb and shoulder area. The muscles showing least hypertrophy were mostly small muscles located in the deeper areas of the carcass, particularly around the spine and in the proximal hindlimb, and in the proximal and distal forelimb.5. Abnormalities of shape in double-muscled cattle may be attributed largely to altered proportions of total muscle and total fat, and to changes in weight distribution within the musculature.
Factors affecting resistance to induced body cooling in newborn lambs of 10 breeds
Authors: Samson Deborah E. , Slee J. 
Published: September 2010

ABSTRACT1. The ability to resist hypothermia was measured in 265 lambs of 10 breeds immersed in a progressively cooling water bath.2. Cold resistance varied significantly between breeds, with hill lambs showing the highest resistance. Hill breeds and feral breeds together had the highest weight-specific cold resistance.3. Cold resistance was positively correlated with birth weight and skinfold thickness.4. Age at test varying from 1 to 60 h did not significantly affect cold resistance.5. Rate of recovery from hypothermia varied slightly between breeds. The feral lambs tended to recover fastest.
The effect of injecting or infusing low doses of bovine growth hormone on milk yield, milk composition and the quantity of hormone in the milk serum of cows
Authors: Hart I. C. , Bines J. A. , James S. , Morant S. V. 
Published: September 2010

ABSTRACTThe effects of administering bovine growth hormone (bGH) on milk production in cattle were examined in two experiments.In experiment 1, a Latin-square design, three groups of four Friesian cows were injected daily with one of two doses of bGH (6 ng/kg and 30 ug/kg; 0·82 unit/mg) or with saline (control) throughout three successive 21-day periods in mid-lactation. At 30 ug/kg daily bGH stimulated a significant increase in milk yield (P < 0·001) and this response increased with the duration of treatment. Changes in the yields of milk fat, protein and lactose closely followed the changes in milk production. The concentrations of milk fat (P < 0·05) and protein (P < 0·05) rose and fell respectively during the 1st week of injections.' A daily dose of 6 ug/kg bGH failed to stimulate an increase in milk yield but milk lactose content was reduced (P < 0·05) during the 2nd and 3rd weeks of treatment. The proportion of milk serum samples containing detectable quantities of the hormone was increased by the higher dose of bGH.In experiment 2 the milk yields of four Friesian cows were measured when bGH (21·0 to 37·9 mg/day) or saline was infused intravenously for 6 days. The infusions produced up to eight-fold increases in plasma bGH. These were within physiological limits, and remained at elevated levels throughout the 24-h period. Three of the cows demonstrated a clear increase in milk production.
The utilization of whole and rolled cereals by ewes
Authors: Vipond J. E. , Hunter E. A. , King Margaret E. 
Published: September 2010

ABSTRACTTwo trials were undertaken to investigate the effect of rolling on the digestibility of barley and oat supplements offered to pregnant ewes at 0·43 kg dry matter per day. In the first trial, with ewes given a basal diet of grass silage ad libitum, rolling barley improved the apparent dry matter digestibility of the diet by 0·036 (s.e. 0·0115) and reduced the excretion of whole grains from 0·127 (s.e. 0·0190) of grain fed to almost nil. Method of storage (dried or treated with propionic acid) had no effect on utilization of whole or rolled barley. Grain excretion was lower with whole oats 0·049 (s.e. 0·0147) than with whole barley. In the second experiment, basal diets containing hay or roots ad libitum were supplemented with whole or rolled barley and oats. Excretion of whole grains was very low on the root-based diets and amounted to only 0·047 (s.e. 0·0177) for the whole barley and hay diet. Excretion of whole grains varied between animals and was shown to be a characteristic of the animal. It was concluded that in most situations grain should be given whole to ewes but that it may be advantageous to roll barley when it is given with silage.
Factors affecting the fractional outflow of protein supplements from the rumen 3. Effects of frequency of feeding, intake of water induced by the addition of sodium chloride, and the particle size of protein supplements
Authors: Elimam M. E. , Ørskov E. R. 
Published: September 2010

ABSTRACTFour experiments were conducted with lactating dairy cows offered a hay and concentrate diet (0·5:0·5) to investigate the effects of (1) the frequency of feeding a completely mixed diet (experiment 1) compared with feeding the concentrate fraction and the roughage fraction separately (experiment 2), and (2) the addition of sodium chloride to a completely mixed diet (experiment 3), on the fractional rate of outflow (FRO) of chromium (Cr)-treated fish meal from the rumen, and on milk yield and composition. The cows were offered the diet at either twice the maintenance requirement (experiments 1 and 2), or 2-5 x maintenance (experiment 3) in a 4 x 4 Latin-square design. The effect of the particle size of the Cr-treated soya bean meal was investigated in experiment 4.The frequency of feeding of the completely mixed diet had no significant effect on the rate of outflow of Cr-treated fish meal from the rumen, or on milk yield or composition. FRO per h were 0·070, 0·085, 0·079 and 0·086 when the diet was offered once, twice, four times or 12 times per day respectively. Increasing the frequency of feeding of the concentrate fraction of the diet had no significant effect on FRO. FRO per h were 0·073, 0·078, 0·081 and 0·081 when the concentrate fraction was offered once, twice, four times or 12 times per day respectively.The addition of NaCl to the diet significantly increased water intake (P < 0·001), but had no significant effects on FRO or milk yield. FRO per h were 0·074, 0·075, 0·076 and 0080 when 50, 265, 529 or 794 g of NaCl were added into the diet respectively. The respective intakes of water were 66·6, 74·1, 88·4 and 101·6 kg/day.The FRO per h of fine particles of Cr-treated soya bean meal was 0·085 and for coarse particles, 0·096. The difference was not significant.
A note on the use of assortative mating in tandem selection
Authors: Garcia C. , Toro M. A. 
Published: September 2010

ABSTRACTComputer simulation was used to study the effect of assortative mating in tandem selection. Selection was applied alternatively for each of two traits of equal economic importance, the mating being assortative for the trait not subjected to selection. Two heritabilities (0·2, 0·4), two selection intensities (20/40, 20]100) and three additive genetic correlations (0·50, 0, —0·50) were considered. Assortative mating gives a response which is 1·03 to 1·10 times that achieved when random mating is employed.
Quantitative estimates of lamb carcass composition 3. Carcass measurements and a comparison of the predictive efficiency of sample joint composition, carcass specific gravity determinations and carcass measurements
Authors: Timon V. M. , Bichard Maurice 
Published: September 2010

SUMMARYInterrelationships between carcass measurements were studied in 83 purebred Clun Forest lambs slaughtered at approximately 80 lb. live-weight and ranging in carcass weight from 29 to 42 lb. Individual carcass measurements did not have a worthwhile predictive value; apart from loin (C) and rib (J) fat depths none of 12 external or internal carcass measurements showed a correlation with carcass composition greater thanr= 0·70. Similarly, none of 9 offal measurements recorded had a worthwhile predictive value. In multiple regression certain combinations of these measurements accounted for as much as 77% of the variation in carcass fat, 64% in carcass muscle and 64 % in carcass bone.The predictive efficiency of sample joint composition, specific gravity determinations and carcass measurements were evaluated in terms of the increased error variance using predicted values and the effect of this increase on sample size in treatment comparisons. Generally the results indicated that increasing treatment group size by relatively few animals is sufficient to absorb the additional error variance arising from the use of predicted values. This is particularly true where treatment differences of the order of one standard deviation exist and where part-carcass dissection values are used.
A Relation between mature weight and time taken to mature in mammals
Authors: Taylor C. S. 
Published: September 2010

SUMMARYThe larger the mature size of a mammal, the longer tends to be the time it takes to mature. In an attempt to quantify this relationship, Brody's (1945) studies on post-natal growth and Weinbach's (1941) study on pre-natal growth are re-examined. Both these authors described growth by attributing to each species a live-weight scaling parameter, an age scaling parameter, and a parameter for age origin. By examining the interrelations of these six pre- and post-natal growth parameters, a general empirical relationship between mature weight and time taken to mature is obtained. The time a species takes to reach any particular degree of maturity, that is any fraction of its mature weight, tends to be directly proportional to its mature weight raised to the 0·27th power. This result is in general agreement with previous theoretical work and with results on the time required to reach adult weight.The simplest way to make use of this general relation is considered. When age measured from an origin at or near conception is divided by the 0·27th power of mature weight, then on this modified scale, the age at which a species reaches a given degree of maturity has an expectation independent of mature weight. This age scale has been called metabolic age, since it amalgamates the properties of Brody's physiological age and Kleiber's metabolic turnover time. The most useful working form, however, is the logarithm of metabolic age which is approximately normally distributed with constant variance at all degrees of maturity. Equations are derived giving the expected metabolic age of a species at any degree of maturity in the range covered by Brody's and Weinbach's growth curves. Metabolic age thus appears to furnish a one-parameter representation of comparative mammalian growth.
Genetic parameters of British Landrace bacon pigs
Authors: Smith C. , Ross G. J. S. 
Published: September 2010

SUMMARYGenetic parameters were estimated among 26 traits in British Landrace bacon pigs. The data involved 2,296 pigs from 250 boars tested at the five British national pig progeny testing stations from 1959 to 1961 inclusive. Separate analyses were performed for each sex and for the litter totals, adjustments being made to the data for differences among periods within stations and for differences in age at start of test and in weight at slaughter. The genetic parameters were estimated from the sire components in a conventional hierarchical analysis of variance.Estimates of heritability and genetic and phenotypic correlations among the 26 traits are presented and discussed. The parameter estimates were in very good agreement with figures obtained in a previous analysis with Large White pigs. They indicate that a large part of the variation and covariation among the 26 traits is genetic in origin, and the traits involved would change in response to selection. Moreover, with regard to their concurrent improvement there were no serious antagonisms in the genetic relationships among the traits studied. There was however, evidence of an interaction of sire and sex of progeny for nine of the 26 traits.A principal component analysis was used in an attempt to summarise the correlations among the 26 traits. The first two components gave a reasonable fit to the correlation pattern and these were associated with fat depth, measures of muscling and dressing-out percentage.
The effect of concentration of milk substitute on the performance of artificially reared lambs
Authors: Large R. V. 
Published: September 2010

SUMMARY1. Six Dorset Horn lambs were reared on each of four different concentrations of reconstituted full-cream dried milk powder (10, 15, 20 and 25 % dry matter). The lambs were fed to appetite four times a day for 3 weeks.2. The lambs consumed significantly more liquid milk at the two lower concentrations. Intake of waterper seincreased with increasing concentration of dry matter.3. There were no significant differences in the consumption of milk dry matter between the treatments, although there was a significant linear trend, with dry-matter intake decreasing with decreasing concentration.4. There were no significant differences between the treatments in live-weight gain from 0 to 3 weeks or from 0 to 10 weeks.5. There were no significant differences in the efficiency of feed conversion between the treatments.6. Examination of the distribution of milk intake within days showed that the proportion of milk voluntarily consumed in the first feed of the day increased with age and with concentration.7. The incidence of scouring was high, but there was no general relationship with treatment.8. Abrupt weaning was not satisfactory for the lambs which had been offered only liquid food for 3 weeks and they had to receive a low level of milk feeding for a further week while they became accustomed to solid food.
Genetic and environmental control of foetal and placental growth in the mouse
Authors: McCarthy J. C. 
Published: September 2010

SUMMARYBirth weight was recorded in the first and second litters of six inbred strains of mice and of all possible crosses between them. The mean birth weight of F1young was significantly greater than that of inbred young in most cases; in no case were they significantly lighter than inbred young at birth.Foetal weight and placental weight were recorded on the 17th daypost coitumin the first litters of four strains and of two pairs of reciprocal crosses. F1foetuses were 13–16% heavier than inbred foetuses on crossing four strains. F1placentae were about 15% heavier than inbred placentae on crossing three strains. Crossbreeding did not affect placental weight in the fourth strain. The significance of these findings is discussed.Analyses of data from individual strains and crosses showed that foetal weight was affected by the number of implants in the same uterine horn and independently by the number in the whole litter. The two independent effects, local and systemic respectively, tended to decrease foetal weight as litter size increased. The independent local effect of litter size on placental weight was different and tended to increase placental weight slightly as the number of implants in the same uterine horn increased.Three different instances of maternal effects on foetal and placental growth were observed.The effects of the litter and the mother on foetal growth are discussed in relation to the physiological basis of environmental variation in pre-natal growth.
Acclimatization of Scottish Blackface sheep to cold. 2. Skin temperature, heart rate, respiration rate, shivering intensity and skinfold thickness
Authors: Sykes A. R. , Slee J. 
Published: September 2010

Closely shorn Scottish Blackface female sheep aged 9–14 months, half on high plane and half on low plane nutrition, were subjected, in climate chambers, to two short acute cold exposures down to −20°C. The acute exposures were separated by two weeks chronic exposure to a moderately subcriticai temperature (+8°C) or to a thermoneutral temperature (+30°C). Most of the sheep showed a greater resistance to body cooling at the second acute exposure (Slee and Sykes, 1967). This increased resistance to hypothermia, defined as acclimatization, was apparently influenced more by acute than by chronic cold exposure. The present paper deals with changes in skin temperature, heart rate, shivering intensity and skinfold thickness which also resulted from cold exposure, and accompanied acclimatization.After acute cold exposure followed by chronic exposure to +8°C the following changes in these parameters were observed:1. Extremity skin temperatures and heart rates were consistently increased at thermoneutral ambient temperatures.2. Vasoconstriction of the extremities and increased heart rate, both of which normally occur during the early stages of cold exposure, were delayed.3. Heart rates at sub-zero ambient temperatures were increased.4. Cold-induced vasodilatation at sub-zero ambient temperatures was increased.After acute cold treatment alone the intensity of shivering during the second acute exposure was reduced. Also the onset of foot vasoconstriction was slightly delayed.A highly significant relationship was observed between shivering intensity and heart rate during cold exposure.Plane of nutrition had less effect on the physiological responses to cooling than did previous cold experience.It was suggested in discussion that the physiological responses associated with acclimatization were: elevated basal metabolic rate, delayed onset of vasoconstriction and delayed metabolic response to cold, and consequent lowering of the critical temperature. Summit metabolism was also increased and shivering intensity reduced during acute cold exposure. Some of these responses could have resulted from either acute or chronic moderate cold exposure. However their persistence, once induced, appeared to depend upon continued exposure to moderate cold.
Some effects of cold exposure, nutrition and experimental handling on serum free fatty-acid levels in sheep
Authors: Slee J. , Halliday R. 
Published: September 2010

Blood serum free fatty acid (FFA) levels have been measured in sheep subjected to: (a) short periods (20–24 hours) of fasting, (b) physical and emotional disturbances associated with experimental handling, and (c) exposure to cold temperatures when either pregnant or unmated.The first two factors acted additively, each causing a small elevation of about 100–200 μ-equiv/litre above the pre-existing FFA level. The effect of short-fasting gradually disappeared during the first 6 hours after feeding; the effect of experimental disturbance lasted less than 2 hours.The effect of severe cold treatment (exposure to approximately 60°C subcriticai ambient temperatures for 2–10 hours) was very marked, producing mean FFA elevations of about 2000 μ-equiv/litre.Mild cold exposure (3−8°C below the critical temperature), even when maintained for several days, produced little change in the FFA levels already typical of either well-fed or short-fasted sheep. Exposures of moderate intensity (25°C below the critical temperature) apparently produced small elevations in short-fasted sheep only.It was concluded that a large increase in FFA level was the normal response to acute cold exposure. Elevations due to other factors were, in the context of these experiments, very small. Within the normal range of response to cold exposure there was considerable individual variation in the degree of FFA elevation, but this variation was not generally related to cold resistance expressed as the ability to maintain rectal temperature. However, a few sheep which failed to raise FFA values to the normal extent did show poor cold resistance.
Inherited variation in carcass composition of Suffolk × Welsh lambs
Authors: Watson J. H. , Broadbent J. S. 
Published: September 2010

Relationships were measured between growth constants for live weight and tissue weights in the hind limb sample joint in 60 Suffolk × Welsh lambs.The lambs were random samples of five male and five female from the single-born progeny of each of six Suffolk rams. They were slaughtered as near to 75 lb live weight as possible and a standard cut of the hind limb, extending up to and including the muscles of the upper thigh and pelvis, was removed from the carcass for dissection.Whilst muscles in the upper thigh, pelvis and abdomen were affected predominantly by sex, sire effects increased and progressively substituted them in passing down the limb.Linear growth in body weight was positively associated with weight of bone and muscle in the sample joint but not with subcutaneous or intermuscu-lar fat.