bluuebunny/crossref_metadata_2025_split huggingface dataset:
Voluntary food intake in relation to body weight among British breeds of cattle
Authors: Taylor St C. S. , Moore A. J. , Thiessen R. B. 
Published: September 2010

ABSTRACTVoluntary food intake and body weight were examined over 4-week intervals between 14 and 70 weeks of age in 306 females from 25 British breeds of cattle. At each age, the relationship of the natural logarithm of voluntary food intake to that of body weight was examined by linear regression both within and between breeds.Of the total variation in voluntary food intake, the proportion accounted for by body weight was extremely high between breeds (phenotypically, 0·80 or more; genetically 0·88 or more, at most ages) but phenotypically low within breeds (0·33 or less). The mean voluntary intake of a breed at any age could be predicted from its mean body weight at the same age with a coefficient of variation (CV) among breeds that declined with age from 0·08 to 0·04. Within breeds, the corresponding CV for individual intake was between 0·12 and 0·15 beyond 9 months of age, and even higher at early ages.Within breeds, the regression coefficient of log intake on log body weight was close to the value of 0·7 at all ages. Between breeds, it was over 0·8 at early ages, declining to about 0·7 beyond 1 year of age. Thus, genetically larger breeds voluntarily consumed relatively more food at early ages compared with later ages. Breed size should therefore be taken into account when recommending food intake requirements. Breed deviations for high and low appetite are discussed.
Comparison of sheep and goats under stall-feeding conditions: roughage intake and selection
Authors: Wahed R. A. , Owen E. 
Published: September 2010

ABSTRACTThree experiments measured intake and assessed quality of roughage refused by individually-fed castrated Saanen goats and Suffolk × Mule wethers, aged 21 months.In experiment 1, in which long, lucerne hay was offered (10 animals per species; 14 days) goats ate more than sheep (33·2 v. 28·3 g dry matter (DM) per kg M daily; P < 0·05). In experiment 2, in which long, ammonia-treated barley straw was offered (eight animals per species; 21 days) consumption was also higher for goats (21·6 v. 16·4 g DM per kg M daily; P < 0·01). Freshly cut, chopped stinging nettle (Urtica dioica L.) was offered with treated straw in experiment 3 (eight animals per species). Over the 10 days, intake of nettle increased linearly and that of straw decreased, but nettle consumption was consistently higher for goats than sheep.In each experiment, food refusals (0·2 of food offered) were of lower nutritive value (lower nitrogen, higher acid detergent fibre, lower digestibility in vitro) than food offered. Throughout, food refusals by goats were of slightly higher nutritive value than food refusals by sheep.It is concluded that both sheep and goats are selective feeders under stall-feeding conditions, but the greater intake of roughage by goats cannot be attributed to their selection of more nutritive components.
The effect of nutrition on the reproductive performance of first-litter sows 3. The response to graded increases in food intake during lactation
Authors: King R. H. , Dunkin A. C. 
Published: September 2010

ABSTRACTSeventy-two animals were used in an experiment to study the response of first-litter sows to graded increases in daily food intake during a 28-day lactation. Six food intakes, ranging from 1·5 to 4·8 kg/day were compared. The results showed that both live-weight loss and backfat loss during lactation increased linearly as food intake decreased (P < 0·01).Subsequent ovulation rate was unaffected by food intake but both weaning to mating interval (Y,, days) and the proportion of sows exhibiting oestrus within 8 days of weaning (Y2)improve d linearly with increase in daily food intake during lactation (X, kg) (P < 0·01); the respective linear regressions being Y, = 39·0 - 6·26 and Y2 = 0·198A - 0·15. A sub-group of 24 gilts which were older at first conception (340·5 v. 213·5 days; P < 0·01) exhibited oestrus sooner after their first litters were weaned (12·8 v. 22·1 days; P < 0·05) than the remaining 48 younger animals.Nitrogen balance increased linearly with food intake (P < 0·01) but even at the highest food intake, nitrogen balance remained negative (−15·5 g N per day). Food intake had no effect on the growth rate of piglets to 3 weeks of age but in the 4th week of lactation there was a quadratic increase in piglet growth rate as sow food intake increased (P < 0·01).
16-androstene steroids in the submaxillary salivary gland of the boar in relation to measures of boar taint in carcasses
Authors: Booth W. D. , Diane Williamson E. , Patterson R. L. S. 
Published: September 2010

ABSTRACTFifteen Large White boars were randomly allocated to three groups of five pigs. The boars were slaughtered over a period of time at one of three live weights: group 1 (pork weight), 63 to 68 kg (mean age 141 days), group 2 (bacon weight), 90 to 97 kg (mean age 203 days) and group 3 (heavy weight), 121 to 133 kg (mean age 268 days). Testes, bulbourethral glands, submaxillary salivary glands, blood and thoracic fat were taken from each pig and the glands weighed and steroids determined in extracts of the submaxillary glands, blood plasma and fat. Testosterone and the boar taint steroid, 5a-androstenone (5a-androst-16-en-3-one) were measured in plasma by radioimmunoassay (RIA). 3a-androstenol (5a-androst-16-en-3a-ol) and 5a-androstenone were determined separately in submaxillary glands by gas-liquid chromatography and together semi-quantitatively by a colour reaction. 5a-androstenone was also determined in submaxillary glands by RIA and in fat by enzyme-linked immunosorbent assay. Mean somatic characteristics differed significantly between the groups, but due to the wide variation in steroid concentrations between individual boars, mean differences for steroid concentrations between groups were not significant.Significant positive correlations were found in boars between bulbourethral gland weight, submaxillary gland weight, concentrations of 3a-androstenol and 5a-androstenone in the submaxillary gland and concentrations of free plasma 5a-androstenone and fat 5a-androstenone (P < 0·05). The application of a simple colour reaction to detect readily extractable 16-androstene steroids (16-androstenes) in submaxillary gland tissue is discussed in relation to other methods for determining boar taint.
A test of a free-access two-level pen for fattening pigs
Authors: Fraser D. , Phillips P. A. , Thompson B. K. 
Published: September 2010

ABSTRACTTwo prototype two-tiered pens were constructed for fattening pigs. The pens consisted of a solid or porous upper floor located 0-8 m above a slatted lower floor, with a short ramp joining the two levels. Food was available only on the upper level and water only on the lower. Eleven groups, each of 15 to 18 pigs were housed in the two-tiered pens for 8 weeks, starting at 10 weeks of age, while matched control groups were housed in a conventional pen offering the same amount of total floor space. During the 1st week, some pigs were slow to adapt to the two-tiered system and average weight gain was lower than in the control pen. Over the 8 weeks, however, weight gain and food conversion ratios were very similar in the two pen types. The animals made effective use of the two levels, and kept the upper level free from dung. Physical condition of pigs in the two-tiered pen was as good as, or better than, that of the controls. The two-tiered design offers several potential advantages in terms of animal production and behavioural problems.
Succinylcholine and halothane as a field test for the heterozygote at the halothane locus in pigs
Authors: Webb A. J. , Imlah P. , Carden A. E. 
Published: September 2010

ABSTRACTReaction to the muscle relaxant succinylcholine was investigated as a possible method of distinguishing the heterozygote from the normal homozygote at the halothane locus. Totals of 54 assumed heterozygotes and 67 assumed homozygotes received intravenous succinylcholine during halothane anaesthesia at 6 to 10 weeks of age. Three separate measures of the duration and severity of the muscular reaction to succinylcholine were all significantly increased in heterozygotes compared with homozygotes. The genotypic difference for one of the three reaction traits was significantly influenced by the day of testing. Due to overlapping distributions for the two genotypes, succinylcholine reactions did not offer a precise method of identifying individual heterozygotes. Although test mating to recessive homozygotes would still be required to be certain of eliminating the halothane gene, the gene frequency among prosepective parents for test mating could be substantially reduced by succinylcholine screening. Due to the expertise and time required, succinylcholine testing would probably only be worthwhile for the production of specialized homozygous lines at nucleus level.
Effect of body condition at calving on the health and performance of dairy cows
Authors: Treacher R. J. , Reid I. M. , Roberts C. J. 
Published: September 2010

ABSTRACTTwo groups of nine British Friesian cows were fed from about 32 weeks before calving to achieve condition scores at calving of 2·5 (thin) and 4 (fat). For 10 weeks after calving all cows were offered 7 kg hay daily in four feeds, with concentrates given five times daily according to appetite.During early lactation, the group of fat cows had lower dry-matter intakes and daily milk yields and yielded less milk protein and lactose than the group of thin cows. The mean yield of milk over the whole lactation was 500 kg less in the fat cows but the difference was not significant. The fat cows lost 48 kg body weight and 1·20 units condition score during early lactation compared with 27 kg body weight and 0·52 units condition score in the thin cows. No difference in reproductive performance was found between the two groups but significantly more cases of disease occurred in the fat cows than in the thin cows.It is concluded that cows that are fat at calving eat less than thin cows, give the same or less milk than thin cows, mobolize more body tissue and lose more weight after calving than thin cows and suffer more disease.
Effects of high levels of body condition and food intake on plasma follicle stimulating hormone, luteinizing hormone, prolactin and progesterone profiles around mating in Greyface ewes
Authors: Rhind S. M. , Leslie I. D. , Gunn R. G. , Doney J. M. 
Published: September 2010

ABSTRACTTwo groups of 19 Border Leicester cf × Scottish Blackface 9 ewes were fed so that ewes of one group were in a very high level of body condition at mating (mean score 3·35) and had a high level of intake. Ewes of the second group were in moderately high condition (mean score 2·74) and were given a live-weight maintenance ration. Ewes in the high group had a higher ovulation rate than those of the moderate group (3·36 v. 2·33) but a lower number of embryos per ewe mated (1·16 v. 1·42). Mean follicle stimulating hormone profiles were similar for ewes of the two groups during the luteal and follicular phases of the cycle before mating and during the subsequent oestrus. Mean prolactin concentrations were higher in ewes of the high group during the follicular phase and oestrus but not during the luteal phase. Mean luteinizing hormone (LH) concentrations were higher in ewes of the high group during the follicular phase and oestrus but not during the luteal phase. Mean LH concentrations were similar for the two groups at all times but the frequency of LH pulses was higher in the high group during the follicular phase.Ewes that were not pregnant at slaughter had abnormal progesterone profiles following mating, abnormal pre-ovulatory LH surges or failed to show oestrus. These abnormalities were not related to gonadotrophin profiles prior to oestrus.
Amino acid requirements of growing pigs 8. The response of pigs from 50 to 90 kg live weight to dietary ideal protein
Authors: Yen H. T. , Cole D. J. A. , Lewis D. 
Published: September 2010

ABSTRACTThe response to dietary lysine when provided as part of an ideal protein was examined in pigs over the range of live weight from 50 to 90 kg. Ninety-six pigs, 32 trios of littermate boars, castrated males and gilts were allocated to eight diets with lysine concentrations of 5·6, 6·2, 7·3, 8·3, 9·3, 10·3, 11·4 and 12·4 g/kg diet and corresponding concentrations of crude protein (CP) from 90 to 186 g/kg diet (all having a digestible energy of 13·38 MJ/kg). Pigs were given food on a restricted scale once daily. With increasing lysine concentration, there was a linear response (followed by a plateau) for growth and carcass characteristics up to dietary lysine concentrations of 91, 7·2 and 8·4 g/kg diet and CP concentrations of 142, 116 and 132 g/kg diet with daily lysine intakes of 22·9, 18·6 and 21·2 g and CP intakes of 357, 290 and 331 g for boars, castrated males and gilts respectively.
Wilting of herbage prior to ensiling: effects on conservation losses, silage fermentation and growth of beef cattle
Authors: Charmley E. , Thomas C. 
Published: September 2010

ABSTRACTA sward of perennial ryegrass was either directly ensiled at 181 g dry matter (DM) per kg fresh weight with formic acid applied at 3·6 1/t fresh material or wilted for 65 h to achieve a DM concentration of 407 g DM per kg. Physical and respiration loss were measured in the field and losses during ensiling were estimated from buried bags. The silages were offered to 58 British Friesian steers, initially 3 months of age and 101 kg live weight (LW). Ten steers were allocated to an initial slaughter group and the remainder were offered the two silages either ad libitum or at two restricted levels of feeding. These animals were slaughtered after a mean period of 112 days to estimate the increments in the components of the body.Loss of DM in the field increased from 4·3 to 86·6 g/kg on wilting and proportionately 0·75 of this additional loss was due to respiration. The fermentation characteristics of the silages were broadly similar except that the concentration of ethanol was higher in the unwilted than in the wilted silage (57·6 v. 5·6 g/kg DM). Losses of DM during ensiling were slightly higher with the unwilted (104·4 g/kg ensiled) than with the wilted (80·1 g/kg) material. Losses of nitrogen were relatively higher and energy losses lower than was the loss of DM.Wilting significantly depressed the digestibility of gross energy from 0·651 to 0·631 (P < 0·001) and at the ad libitum level steers ate proportionately 006 more wilted silage (P > 0·05) resulting in similar intakes of digestible energy. At the ad libitum level of feeding steers given wilted silage gained more LW (+55 g/day) and empty-body weight (+64 g/day) than those given unwilted silage (P < 0·05). However, steers given wilted silage contained less fat and energy in the empty body at slaughter than those given unwilted silage. Thus, wilting did not influence the efficiency of utilization of digestible energy for energy retention nor the efficiency of utilization of dietary protein for protein gain. Since efficiencies by the animal were similar and also the increased field loss on wilting was partly compensated for by a reduced silo loss, it is concluded that the proportion of energy and protein in the standing crop retained by the steers is unaffected by wilting (65 and 64 kJ/MJ and 125 and 138 g/kg N for unwilted and wilted systems respectively). Further work is needed to establish the effect of wilting for a shorter period than in the current trial by increasing the drying rate of herbage.
Breed and sex differences in equally mature sheep and goats 1. Growth and food intake
Authors: Thonney M. L. , Taylor St C. S. , McClelland T. H. 
Published: September 2010

ABSTRACTGenetic size-scaling accounts for most of the variation found among mammalian species in food intake and growth rate, with food conversion efficiency independent of the body size of the species. Is the same true of breeds and strains within species?Animals from Soay, Welsh Mountain, Southdown, Finish Landrace, Jacob, Wiltshire Horn and Oxford Down sheep breeds and from a breed of feral goats were grown to 0·40, 0·52, 0·64 or 0·76 of the mean mature weight of their breed and sex. Food was offered ad libitum and individually recorded.Allometric growth coefficients were obtained for fleece weight, femur weight and femur length. Fleece was late maturing and femur early.Breed and sex size-scaling coefficients, obtained by regression of breed and sex means on mature size, were similar to those found at the species level for age from conception to slaughter, time taken to mature and food conversion efficiency. Coefficients were higher than expected for total and daily food consumption, especially at early stages of maturity. Most breed coefficients were close to expectation while sex coefficients were somewhat higher than expected.There were significant breed deviations: Welsh Mountain, Oxford Down and probably Soay sheep required less time and Jacob sheep and feral goats required more time to mature than expected from differences in mature size. Soay and Welsh Mountain sheep appeared to be more efficient and feral goats and Jacob sheep less efficient food converters over the same maturity interval.
Changes in body composition relative to weight and maturity of Australian Dorset Horn rams and wethers 4. Adipocyte volume and number in dissected fat partitions
Authors: Thompson J. M. , Butterfield R. M. 
Published: September 2010

ABSTRACTThe effect of castration on the cellular characteristics of dissected fat partitions was examined in 20 Dorset Horn rams and 20 Dorset Horn wethers. Cellular characteristics of dissected carcass (subcutaneous and intermuscular partitions) and non-carcass (kidney fat, omental and mesenteric partitions) fat partitions were examined in 13 mature animals, and the rate of change in adipocyte volume relative to the change in chemical-fat weight in that partition, examined in 27 immature animals.Mature wethers had a greater concentration of chemical fat in the subcutaneous fat partition than mature rams (917v. 885 g/kg, respectively). This, in combination with a greater weight of dissected subcutaneous fat, resulted in a greater weight of chemical fat in the subcutaneous partition of wethers compared with rams. Mature wethers had larger adipocytes than mature rams in all dissected fat partitions, with the largest increase in the subcutaneous and omental fat partitions. The increased adipocyte volume in the dissected fat partitions in mature wethers resulted in a smaller total estimated number of adipocytes in all carcass and non-carcass fat partitions compared with mature rams.Standardized allometric coefficients for adipocyte volume relative to chemical-fat weight in that partition showed that increases in chemical-fat weight were due to a combination of hypertrophy and hyperplasia. In the omental and kidney fat partitions, hypertrophy contributed more to the increase in chemical-fat weight in wethers compared with rams.
Effects of floor area allowance on performance of growing pigs kept on fully slatted floors
Authors: Edwards S. A. , Armsby A. W. , Spechter H. H. 
Published: September 2010

ABSTRACTThe experiment compared four different space allowances for growing pigs housed on fully slatted floors. Space allowance (A m2) was defined in relation to live weight (M kg) of the pigs according to the equation A = kM0·67, using values for the constant (it) of 0·024, 0·027, 0·030 and 0·034. Six replicate pens of 12 pigs were housed on each treatment in a controlled environment building. Food was given ad libitum and from 34 kg until slaughter at 85 kg pigs were individually weighed each week and the pen size was adjusted according to the appropriate equation. Increasing space allowance increased live-weight gain (844, 862, 883, 897 (s.e.d. 14·4) g/day). Differences in killing-out proportion reduced the effect on final carcass weight (63·3, 63·9, 64·1, 64·5 (s.e.d 0·82) kg). Daily food intake was unaffected by treatment but food conversion ratio was significantly poorer at the lowest space allowance (2·70, 2·56, 2·60, 2·59 (s.e.d. 0·043) kg/kg). Economic analyses of the results indicated an adverse effect on profitability of space allowance less than that defined by the equation A(m2) = 0·027 M0·67 (kg). A minimum allowance defined by the equation A (m2) = 0·030 M0·67 is recommended in commercial practice for pigs in fully slatted housing.
Effect of litter size on herbage intake at pasture by ewes and their progeny
Authors: Vulich S. A. , O'Riordan E. G. , Hanrahan J. P. 
Published: September 2010

AbstractThirty-four mature ewes (17 rearing twins and 17 rearing singles) were used to examine the effect of litter size on herbage intake at pasture by ewes over the course of lactation; intake by their lambs during weeks 13 to 15 of lactation was also evaluated. Daily organic matter intake (OMI) was estimated using the n-alkane technique. Ewes and lambs rotationally grazed 19 × 0·15-ha paddocks during the experimental period which extended from week 2 of lactation to weaning at week 15 of lactation. Sward conditions were maintained steady throughout with daily OM allowance per ewe varying between 4·6 and 5·7 kg and dry matter digestibility between 763 and 858 g/kg DM.Throughout lactation OMI and OMI per kg body weight were higher for twin-rearing ewes (P < 0·05) than for ewes rearing singles: 2·50 and 2·26 kg/day, and 38 and 32 g/kg per day, respectively. Intake reached a maximum on weeks 6 to 7 of lactation. From weeks 13 to 15 of lactation, OMI and OMI per kg body weight for single- and twin-reared lambs were 1·09 and 1·14 kg/day, and 31 and 36 g/kg per day, respectively.The combined food intake per dam-offspring unit for weeks 13 to 14 of lactation for a ewe plus her single lamb was 2·8 kg OM per day compared with 4·3 kg OM per day for a ewe plus her two lambs. The repeatability of average weekly intake by ewes was 0·39 over the course of lactation and 0·40 for lambs over the 13 to 15 week period. Repeatability estimates for ewes increased slightly when data from weeks 3 to 7 and weeks 13 to 14 was analysed separately (0·42 and 0·53, respectively).
Partial milking of cattle in smallholder herds on the Accra Plains: some factors affecting daily partial milk yield and milk composition
Authors: Okantah S. A. 
Published: September 2010

AbstractDaily partial milk yield of Sanga cows in 13 smallholder agropastoralist herds at two locations on the Accra Plains was recorded through monthly sampling. Estimates of mean daily partial milk yield and milk composition were computed from 1266 observations. The unadjusted mean daily partial milk yield was 875 (s.e. 11) g. The composition of milk: total solids (TS), fat (F) and solid-not-fat (SNF) were 131 (s.e. 14), 41 (s.e. 11) and 90 (s.e. 7) g/kg respectively. Least squares estimate of mean daily partial milk yield were 808·2 and 462·4 g with average s.e. of 41·8 for wet and dry season respectively. The wet and dry season differences in daily partial milk yield, TS and F were highly significant (P < 0·01). Seasonal difference in SNF was not significant.Herd difference in partial milk yield, TS, F and SNF were highly significant (P < 0·02). There were no significant effects of location on daily partial milk yield and SNF, although location effects on F and TS were significant (P < 0·05). The highest milk yield was observed in cows in third lactation and the lowest in cows in seventh lactation (P < 0·01). Daily partial milk yield peaked in the 3rd month of lactation. On average, lactation length was 210 to 240 days. Both linear and quadratic effects of stage of lactation were highly significant (P < 0·01). Lactation curve parameters for partially milked cows were also estimated. The implications of the results for milk production in sub-Saharan Africa were discussed.