bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of stage of harvest and fineness of chopping on the voluntary intake and digestibility of maize silage by young beef cattle
Authors: Wilkinson J. M. , Penning Ines M. , Osbourn D. F. 
Published: September 2010

ABSTRACTWhole-crop maize was harvested at 20% (L), 29% (M) and 38% (H) dry-matter (DM) content, chopped to 7·67 mm (F) or 33·3 mm (C) average particle length and ensiled. The six silages were offered ad libitum to 36 entire male calves (initially 96 kg live weight), together with supplements of urea and dried ryegrass, for 42 days. Voluntary intake and the apparent digestibility of the diets were measured. Intake of DM was not affected by the DM content of the silages, but was higher for F than C by 6·6% (P<0·01). Apparent digestibility of DM, organic matter and cell walls decreased with increasing silage DM content (P<0·001) and was higher for F than C (P < 0·01).
Heritability of milk yield and composition at different levels and variability of production
Authors: Hill W. G. , Edwards M. R. , Ahmed M.-K. A. , Thompson R. 
Published: September 2010

ABSTRACTAnalyses of variance were conducted on first lactation milk, fat and protein production records in England and Wales of daughters of British Friesian sires. Herds were split on milk yield into high and low levels of mean production and, in subsequent analyses, into high and low levels of within herd variance and coefficient of variation using all first lactation records. Data were then extracted on daughters of 798 young sires undergoing progeny test and on 118 widely used proven sires to generate connections. Least squares analyses were conducted within levels and genetic correlations estimated from the covariance of sire effects. W ith data split on mean yield, the heritability of milk yield was 0·24 at the low level and 0·30 at the high level, that of log transformed yield being 0·25 and 0·35 respectively.With data split on variance the corresponding figures were 0·24, 0·30, 0·27 and 0·36 respectively, and when split on coefficient of variation, 0·22,0·26,0·26 and 0·32. There were similar increases for fat and protein yield, proportionately smaller increases for fat and protein content.Genetic correlations were close to 1·0 between high and low levels for all traits on all criteria of data splitting. As a consequence progeny testing of bulls is rather more accurate at high mean or variance of production levels and data can be combined optimally without scaling. Cows of the highest predicted value using an index will be found in high variance herds.
Genetics of leg weakness in performance-tested boars
Authors: Webb A. J. , Russell W. S. , Sales D. I. 
Published: September 2010

ABSTRACTGenetic relationships among leg and performance traits were estimated for 23 975 Large White and Landrace boars fed twice daily to appetite from 27 to 91 kg live weight at Meat and Livestock Commission testing stations between 1966 and 1972. For each boar, an overall leg score was derived as the sum of scores for 19 individual leg traits categorized as ‘absent’ (0), ‘slight’ (1) or ‘severe’ (2) at 91 kg. Heritabilities of leg score were 017 ± 0·03 in Large White and 0·19 ± 0·04 in Landrace. Genetic correlations with a visual ‘leg action’ score on a scale from 1 to 5 averaged 0·93 ± 0·02 over breeds. Genetic and phenotypic correlations between leg scores on the same boars at 27 and 91 kg averaged 0·50 ± 0·17 and 0·15 ± 0·01 respectively.Both breeds showed significant adverse genetic correlations ranging from 0·20 ± 0·10 to 0·40 ± 0·08 between leg score and boar ultrasonic backfat. From slaughtered littermates, leg scores showed favourable genetic correlations with eye-muscle area (0·30 ± 0·10) and killing-out proportion (0·35 ± 011) in Large White and unfavourable correlations with carcass length (0·31 ± 0·10), lean content (0·30 ± 0·14) and backfat (0·33 ± 0·11) in Landrace. There were no associations with growth rate, feed efficiency or the performance index on which boars are selected. The study indicates that leg condition and fatness are adversely genetically related, but that selection on the present national performance index would not be expected to cause a rapid decline in leg condition. Culling on leg score would be expected to reduce the frequency of leg weakness.
A note on the effect of melatonin feeding on the initiation of ovarian activity and on plasma prolactin levels in lactating and non-lactating red deer hinds
Authors: Nowak Rachel , Elmhirst R. N. , Rodway R. G. 
Published: September 2010

ABSTRACTMelatonin was fed daily at 14.00 h to eight non-lactating and six lactating hinds. Feeding was begun on 27 July 1983 (day 1) and continued until 21 September (day 57). Six non-lactating hinds were used as controls. Blood samples were taken about every 10 days from day 42 until day 73. Plasma progesterone and prolactin were determined by radioimmunoassay. Progesterone values of greater than 0·63 μg/1 were taken to indicate the presence of a corpus luteum and that the animal had ovulated. In the melatonintreated, non-lactating group seven of the eight hinds showed ovarian activity compared with two of the six controls (P < 0·01). None of the lactating hinds treated with melatonin showed evidence of ovarian activity. In both the lactating and non-lactating hinds treated with melatonin, prolactin levels were never greater than the detection limit of the assay (7·4 μg/l), while, in the control hinds mean prolactin levels were elevated on all but the last sampling day. It is, therefore, possible to induce early ovarian activity in non-lactating red deer hinds by feeding melatonin. However, although melatonin treatment similarly depressed plasma prolactin levels in both lactating and non-lactating hinds, it was unable to overcome the inhibitory effect of lactation on reproduction.
Bioenergetics, bioengineering and growth
Authors: Webster A. J. F. 
Published: September 2010

ABSTRACTThe effects of conventional and novel methods for the manipulation of growth in meat animals are reviewed within the context of the fundamental laws that determine the biological efficiency of energy conversion. Interspecies comparisons reveal large differences in the energetic efficiency of growth between mammals and birds. The similarity between mammals of different sizes is remarkable, both between and within species, which suggests that manipulation of growth rate per se has little effect on efficiency. The best way to improve the efficiency of growth is to maximize the conversion of metabolizable energy (ME) to lean tissue at all stages of maturation. The principal destination of ME is heat, however thermogenesis linked to essential metabolic functions is resistant to manipulation. It is more profitable to manipulate the partition of retained energy between protein and fat. Whether this is achieved by nutrition, conventional breeding or bioengineering, it is necessary to ensure that it does not compromise the normal health and vigour of the growing animal.
Sweet lupin seed meal as a protein source for growing pigs
Authors: Taverner M. R. 
Published: September 2010

SUMMARYThe growth performance, carcass quality and digestive efficiency of growing pigs were used to compare sweet lupin seed meal (SLSM) to soya bean meal and meat meal as a source of supplementary protein to wheat in diets for pigs, and to study the influence of low levels of lysine and methionine, high levels of crude fibre and oil, and possible toxic factors in SLSM on the use of SLSM in such diets.The growth rate and food utilization of pigs between 20 and 80 kg live weight were in the order soya bean meal > SLSM > meat meal, but only the difference between soya bean meal and meat meal was significant. These feeds did not differ significantly in their effects on the proportion of lean in the ham. Adding lysine to the SLSM diet improved growth performance but adding methionine did not. The digestibility of crude fibre in diets containing SLSM was greater than that in diets containing soya bean meal; the digestible energy contents of SLSM and soya bean meal were 4·13±0·05 and 4·16±0·08 Mcal/kg dry matter, respectively. Pigs fed on a diet containing 27·5% SLSM grew faster but utilized food as efficiently when fed ad libitum as on a restricted scale of feeding. The subcutaneous fat of pigs fed on SLSM had a higher iodine number than that of pigs fed on soya bean meal.
Observations on the relationships between the nutrition, milk yield, live weight and reproductive performance of dairy cows
Authors: Ducker M. J. , Morant S. V. 
Published: September 2010

ABSTRACTOver a 2-year period, 80 dairy cows were used to investigate the relationship between nutrition and fertility. The plane of nutrition of half the cows was raised for a 9-week period around the expected time of artificial insemination in both breeding seasons. The net effect was that the high-plane cows received 15% extra metabolizable energy during the 9-week period. This was achieved by giving these cows a high-energy concentrate (calculated value 13·1 MJ metabolizable energy per kg dry matter), whereas the control cows received a concentrate with a calculated energy density of 12·5 MJ metabolizable energy per kg dry matter. All cows received a basal ration that supplied an average of 75 and 80 MJ metabolizable energy per cow per day in the 2 years, respectively. Control cows received their calculated amount of dry matter using the control concentrate, whereas the high-plane cows received their calculated dry matter using the high-energy concentrate. The high-plane cows also received an additional 0·5 kg dry matter per head per day of their concentrate. They also received additional concentrates (2 kg per head per day) for 8 weeks, commencing 12 weeks before the second calving.There was no effect of dietary treatment on the reproductive performance of the cows, although some measures of milk yield, live weight and body condition were affected significantly.Analysis of data from all cows, regardless of treatment group, showed that the probability of pregnancy to an insemination was most strongly associated with milk yield on day 21 of lactation. Only the cumulative yield to day 21 was related to the probability of pregnancy after accounting for the trend with yield on day 21. The chance of pregnancy was lower in cows whose milk yields on day 21 were high but, among cows with similar yields on day 21, those with the higher cumulative yields at that time tended to become pregnant more readily. Thus both yield per se and rate of increase in yield in early lactation were associated with subsequent reproductive performance.
Digestion and utilization of straw. 1. Effect of different chemical treatments on degradability and digestibility of barley straw by sheep
Authors: Fahmy S. T. M. , Ørskov E. R. 
Published: September 2010

ABSTRACTBarley straw was treated with anhydrous ammonia, sodium hydroxide, ammonia plus sodium hydroxide, sulphuric acid or ammonia plus sulphuric acid to study the effect on the digestibility of straw and the degradability of the straw in the rumen of sheep.In experiment 1 four wethers fitted with rumen cannulae were given ammonia-treated straw to appetite and were used for measuring the dry- and organic-matter degradability of straw in the rumen after different in sacco incubation times. The organic-matter degradability (g/kg) after 48 h in sacco incubation was 459, 603, 576 and 660 for control, ammonia, sodium hydroxide and ammonia plus sodium hydroxide-treated straw respectively. Each treatment improved the degradability significantly (P < 0·01). The effect of ammonia plus sodium hydroxide treatment on rumen degradability of straw was additive (P < 0·05).In experiment 2 the treated straws studied in experiment 1 were given to four wethers in a 4 × 4 Latin-square design, to measure the voluntary intake, digestibility, water consumption and urine excretion. The digestibility (g/kg) and daily intake of digestible organic matter (g/kg M0·75 per day) were 554, 12·5; 628, 24·7; 653, 19·7; and 668, 24·3 for the control, ammonia, sodium hydroxide and ammonia plus sodium hydroxide-treated straws, respectively. Intake of ammonia-treated straw was significantly greater than for sodium hydroxide-treated straw (P < 0·01). The water consumption and urine excretion by sheep were increased significantly by sodium hydroxide and ammonia plus sodium hydroxide treatments (P < 0·01).In experiment 3, either straw or ammonia-treated straw were treated with 20, 40 and 60 g sulphuric acid (200 ml/1 solution per kg). The degradability of the acid-treated straws was measured using three wethers fitted with cannulae and given ammonia-treated straw to appetite. The dry-matter degradabilities (g/kg) after 48 h in sacco incubation were 52·0, 53·9, 58·7 and 67·4 for the control, and 20, 40 and 60 g acid per kg treatments, whereas the values were 61·3, 60·4, 68·4 and 69·4 for the ammonia-treated straw, and 20, 40 and 60 g acid per kg treatments respectively. There was a significant effect of acid treatment and ammonia treatment on dry-matter degradability.
Digestion and utilization of straw. 2. Effect of different supplements on the digestion ammonia-treated straw
Authors: Fahmy S. T. M. , Lee N. H. , Ørskov E. R. 
Published: September 2010

ABSTRACTFour experiments with sheep fitted with rumen cannulae were conducted to investigate whether the rate of digestion of ammonia-treated straw, estimated as disappearance of dry matter from nylon bags in the rumen, might be increased by supplements of either soya bean meal, sucrose or sugar beet pulp at a level of 0·1, or by increasing the concentrations of dietary soluble micro and macro minerals.There were no differences among treatments in rate and extent of digestion of straw due to supplementations.In another experiment, the effect of increasing the proportion of molassed sugar beet pulp or rolled barley on rate of digestion of ammonia-treated straw was investigated. A greater proportion of sugar beet pulp (0·45) could be included in the diet before the rate of digestion was decreased in comparison with rolled barley (0·35).Assuming that the digestibility of the sugar beet pulp and the rolled barley was not changed by the increasing proportion in the diet, it could be calculated that the digestibility of straw was reduced from 0·538 with straw alone to 0·403 with the sugar beet pulp and to 0·218 with the rolled barley supplement when the supplements were included at a level of 0·70.
Effect of pattern of lighting and time of birth on occurrence of puberty in female goat kids
Authors: Amoah E. A. , Bryant M. J. 
Published: September 2010

ABSTRACTThirty-six British Saanen female kids, born between either 20 March and 6 April (E) or 10 April and 16 June (L), were reared under three different patterns of lighting — a constant 18-h light: 6-h dark (C); or a weekly step-wise reduction from 18-h to 10-h light: 14-h dark over 10 weeks, commencing at either 6 (R6) or 10 (R10) weeks of age. Vasectomized males were used to test for oestrus; blood samples were collected to determine plasma progesterone concentration. Thirty-three goats attained puberty; all but two kids showed oestrus at first ovulation. The mean ( ± s.d.) age and live weight at puberty were 174·6 (± 4·1) and 141·7 (± 4·3) days (P < 0·001), and 28·6 (± 0·9) and 22·8 (± 1·0) kg (P < 0·001), for E and L treatments, respectively. For R6, R10 and C treatments, the ages and weights wer e 151·6 (± 4·7), 160·4 (± 5·2) and 164·7 (± 4·9) days (NS), respectively, and 24·5 (± 1·1), 25·3 (± 1·2) and 27·8 (± 1·1) kg (NS), respectively. A significant date of birth × lighting-pattern treatment interaction was found for date at puberty (P < 0·001), with puberty occurring earlier for E than L kids only when a reduction in daylength occurred. Puberty occurred earlier on R6 than R10 treatments only for L kids.
The efficacy of dietary avoparcin for improving the performance of growing-finishing beef cattle
Authors: Cuthbert N. H. , Thickett W. S. , Smith H. 
Published: September 2010

ABSTRACTThe response to avoparcin in cattle diets was examined in two trials. In trial 1 compound diets containing 0, 15, 30 or 60 mg/kg avoparcin were given to 32 British Friesian bulls from 231 kg body weight to slaughter at a mean body weight of 422 kg. In trial 2 diets containing 0, 15, 30 or 45 mg/kg avoparcin and composed of equal portions of dry matter (DM) from grass silage and compound food were given to 64 British Friesian steers over a 12-week period from 258 kg body weight to 340 kg body weight.There was a significant growth response of 120 g per head daily in trial 1 and 80 g per head daily in trial 2 to inclusion of 15 mg/kg avoparcin in the diet compared to the control diet without avoparcin. Food conversion efficiency of diets with 15 mg/kg avoparcin was improved by a reduction of 0·52 and 0·61 kg DM per kg live-weight gain respectively in the two trials. There was no further growth response or improvement in food conversion with higher levels of avoparcin with the diets used, the type of cattle employed and the management which applied in these trials. These findings are in good agreement with those previously published.
Cattle transferrins and milk production
Authors: Jamieson Alan , Robertson Alan 
Published: September 2010

1. An analysis has been made of the association between transferrin genotype and progeny test for both milk yield and fat content in a sample of 879 bulls of five dairy cattle breeds, the majority used in artificial insemination in Great Britain. Although significant effects were found in only one of the ten analyses when the breeds were considered separately, a significant effect on milk yield was found when the results from all breeds were combined. A significant effect was not found for fat content, although the effects of the allele substitutions were in the opposite direction to that on milk yield in five cases out of six.2. Although our results were in the same direction as those of Ashton, the effects were smaller. It was estimated that the locus accounted for 1·1% of the genetic variation in yield and 0·4% of the genetic variation in fat content.3. Some information based on the production records of 178 experimental cows with known genotypes was also analysed. For milk yield, the pattern of effects was similar to that in the sire data though the differences were much larger. The variance removed by fitting constants was not statistically significant for milk yield or fat content. It was estimated that the sire data contained some fifty times as much information as did the cow data.
Effects of housing and rearing on age at puberty and libido in boars
Authors: Thomas H. R. , Kattesh H. G. , Knight J. W. , Gwazdauskas F. C. , Meacham T. N. , Kornegay E. T. 
Published: September 2010

ABSTRACTThe effects of type of housing (outdoors on earth v. confinement on concrete) and system of rearing (single v. group) on age at puberty and expression of libido in boars were examined. Boars kept on earth lots and reared in groups reached puberty earlier and demonstrated greater sexual aggressiveness compared with contemporary boars maintained under other treatment combinations. Additionally, the effect of rearing boars either in all-male groups or withprepubertal gilts was examined. Age at puberty was not affected by the presence of females, but boars reared without females attained a higher libido score.
Online reading: a preliminary study of the impact of integrated and split-attention formats on L2 students’ cognitive load
Authors: Al-Shehri Saleh , Gitsaki Christina 
Published: September 2010

AbstractCognitive load theory has been utilized by second language acquisition (SLA) researchers to account for differences in learner performance with regards to different learning tasks. Certain instructional designs were shown to have an impact on cognitive load and working memory, and this impact was found to be accentuated in a multimedia environment where there is a variety of interacting elements and tools that can lead to cognitive overload and consequently reduced learning outcomes. This study investigated the influence of split-attention and integrated instructional formats on students’ cognitive load and how they might facilitate second language online reading and vocabulary learning. Twenty English as a Second Language (ESL) intermediate students studying at an Australian language institution were randomly assigned to four conditions: SAND (Split-Attention No Dictionary), SAOD (Split-Attention with Online Dictionary), IFND (Integrated Format No Dictionary), and IFOD (Integrated Format with Online Dictionary). Subjects were asked to complete an online reading comprehension task in which subjects tested under the SAND and SAOD conditions were exposed to a typical reading text followed by comprehension questions, whereas subjects in the IFND and IFOD conditions were exposed to a reading text where the comprehension questions were physically inserted within the reading text. Under the SAOD and IFOD conditions, subjects had access to an online dictionary. Results showed that the integrated reading format was found to facilitate students’ reading comprehension more than the split-attention format. Also, students who had access to the online dictionary in the SAOD and IFOD groups performed better on the vocabulary test, but spent more time on the reading task than the other two groups. Furthermore, participants in the split-attention format group looked up more words than their counterparts in the integrated format group. The results of the present study have certain implications for multimedia instructional designers and ESL teachers.
Reproductive performance and milk production of the improved Awassi breed as compared with its crosses with the Booroola Merino
Authors: Gootwine E. , Bor A. , Braw-Tal R. , Zenou A. 
Published: September 2010

AbstractOvulation rate, embryo survival, lamb production, lamb survival and milk production of Awassi and BooroolaAwassi crossbred ewes, kept indoors, were compared. Awassi were non-carriers while Booroola × Awassi (F1) and about half of 3/4 Awassi-1/4 Booroola (BQ) ewes were heterozygous at the FecB gene. Mean ovulation rate increased by 1·5 to 1·6 corpora lutea per ewe ovulating and prolificacy by 0·7 lambs born per ewe lambing in Fj and BC1 (B+) ewes as compared with Awassi. Embryo survival rates in BC1 ewes with two, three and four ovulations were 0·83, 0·68 and 0·71, respectively. Lamb survival rates at 1 day of age were 0·93, 0·90 and 0·77 and average birth weight was 4·9, 4·0 and 3·0 kg for lambs born as singles, twins and triplets, respectively. Average milk production of the Awassi was 506 I per ewe per lactation. F1 and BC1 ewes produced respectively, proportionately 0·48 and 0·63 of the Awassi milk production and there was no significant difference in milk production between BC1,(B+) and BC1(++) ewes. The relatively low milk production of the Booroola Awassi crosses suggests that heterosis and recombination effects on milk production were negative. It is concluded that incorporation of the B allele per se can increase lamb production in the Awassi without affecting its milk production.