bluuebunny/crossref_metadata_2025_split huggingface dataset:
An investigation of the changes in sites of milk storage in the bovine udder over two lactation cycles
Authors: Dewhurst R. J. , Knight C. H. 
Published: August 2016

AbstractThe objective of this work was to investigate phenotypic sources of variation in the sites of storage of milk within the udder. Ten primiparous and 10 multiparous dairy cows were studied over two successive lactations in order to investigate the effects of age, parity and stage of lactation. Cistern and alveolar milk volumes were estimated at a standard 8 h after a normal morning milking by catheter drainage and machine milking with oxytocin respectively. Measurements were made at approximately 9, 20, 30 and 42 weeks of the initial lactation and weeks 1, 4, 7, 10, 20 and 34 of the subsequent lactation. In the initial lactation, there was a significant difference between primiparous and multiparous animals in the rate of decline of total daily milk yield (P&lt; 0·001). Cistern milk yield (kg/8 h) from multiparous animals declined over the lactation whilst that for primiparous animals was maintained. The effect was shown as a significant interaction effect (P&lt; 0·05). For both multiparous and primiparous animals cistern proportion (cistern yield divided by total milk yield at 8h after a normal milking), increased over the lactation (P&lt; 0·001). This was largely a consequence of the reduced total milk yield. Eleven animals were studied through the subsequent lactation. Cistern yield followed a lactation curve of similar form to that for total yield. The decline in cistern yield over this lactation was much greater than the decline with multiparous animals in the previous year. This may, in part, reflect a faster decline in total daily yield. Stage of lactation and parity must be taken into account if a standardized evaluation of cistern characteristics is to be obtained.
Effect of fish-meal supplementation and β-agonist administration on adipose tissue metabolism in steers given silage
Authors: Dawson J. M. , Essex C. P. , Walsh A. , Beever D. E. , Gill M. , Buttery P. J. 
Published: August 2016

AbstractThe effect of fish-meal supplementation or cimaterol administration on the composition, cellularity and metabolism of subcutaneous and perirenal adipose tissue was examined in young Friesian steers given grass silage. Animals (approx. 117 kg live weight) received either silage alone (group C; no. = 6) or supplemented with fish meal (150 g/kg silage dry matter; group FM; no. = 6) or cimaterol (0·06 mg/kg body weight per day) administered via osmotic minipumps (group CIM; no. = 6) for a period of 6 weeks. Samples of perirenal and subcutaneous adipose tissue obtained at slaughter were used for determination of tissue composition andin vitrorates of lipogenesis, lipolysis and substrate oxidation. FM animals showed significantly greater live-weight gains (0·61 kg/day) compared with C (0·21 kg/day,P&lt; 0·001) while CIM animals had significantly lower rates of gain (0·04 kg/day,P&lt; 0·05). This was considered to be related to increased heat loss from the β-agonist-treated animals as a result of very cold weather encountered during the experimental period. CIM administration reduced adipocyte size suggesting an increased number of cells per g tissue. Both lipolytic and lipogenic rates were reduced by cimaterol and there was some evidence that the response to insulin was diminished, at least with respect to substrate oxidation. FM increased lipogenesis from acetate and acetate oxidation rates in subcutaneous adipose tissue with similar trends in perirenal tissue. The results indicate that both fish-meal supplementation and cimaterol administration caused substantial changes in adipose tissue metabolism as determined usingin vitroprocedures, even though the magnitude and direction of the changes were not in strict accord with estimates of net fat accretion from relatedin vivostudies.
Effect of ammonia treatment of barley straw on the dynamics of its degradation in the rumen
Authors: Fondevila M. , Castrillo C. , Gasa J. , Guada J. A. 
Published: August 2016

AbstractTwo experiments were designed to examine the effects of ammonia treatment of barley straw on rumen environmental conditions for fibre degradation, and to determine the effect of treatment on the soluble and insoluble fractions of straw. In experiment 1, rumen pH, and ammonia-nitrogen and volatile fatty acid concentrations in the rumen of sheep receiving untreated (US1) or ammonia-treated (TS1) straw were recorded. Also, both straws were incubated in the rumen of both groups of animals. There were no significant differences (P&gt; 0·05) within rumen parameters, except for butyrate proportion, which was higher (P&lt; 0·01) with TS1. Dry matter and neutraldetergent fibre disappearances of TS1 were higher (P&lt; 0·001) than those of US1 at all the incubation times. Degradation of both straws in US1-fed sheep was not smaller, and in some periods of incubation was even greater, than in TS1-fed animals. In experiment 2, samples of untreated (US2) and treated (TS2) straw were incubated in wethers offered a mixture (50:50) of alfalfa hay and straw. Samples of US2 and TS2 were soaked in autoclaved rumen fluid to measure their solubility. It was clear that, although treatment increased the soluble fraction of US2 and TS2 by 52 and 65 g/kg respectively, from 0 to 72 h of incubation, increasing the differences between straws from 45 to 58 g/kg in that period, actual microbial action on the treated roughage was the more important factor, accounting for a difference between US2 and TS2 of 131 g/kg after 72 h incubation.
The effect of a diet containing cyanogenetic glycosides on the selenium status and the thyroid function of sheep
Authors: Gutzwiller A. 
Published: August 2016

AbstractSix ewes were given a white clover/grass silage with a high content of cyanogenetic glycosides during the last 69 to 97 days of pregnancy (group CN+), while the five ewes of the control group (group CN−) received a white clover/grass silage with a low content of cyanogenetic glycosides during the last 67 to 92 days of pregnancy. Uniodized salt was the only mineral supplement offered. The daily intake of cyanide (in the form of cyanogenetic glycosides) and of selenium per animal was 1000 and 60 mg of cyanide and 30 and 23 μg of selenium in group CN+ and CN− respectively. Initial erythrocyte glutathione peroxidase activity (GPx) was identical in both groups. Two weeks before parturition GPx activity was significantly lower in the ewes of group CN+ than in the ewes of group CN−. The newborn lambs of the group CN+ had significantly lower erythrocyte GPx activities (P&lt; 0·01) and tended to have higher plasma creatine kinase activities (P= 0·07) than the lambs of the group CN−. The results show that the intake of cyanogenetic glycosides affects the selenium status of sheep and increases the susceptibility of lambs to nutritional myopathy if the selenium content of the ration is marginal.Plasma thyroxine concentrations in the ewes in group CN+ were not reduced but their lambs tended to have slightly lower levels immediately after birth than the lambs of group CN− (P= 0·25). The intake of cyanogenetic glycosides presumably had no or at most only a slight effect on thyroid function, presumably because the body iodine reserves of the ewes were sufficient to offset the goitrogenic effect of thiocyanate.
The food intake, performance and carcass characteristics of two pig genotypes grown to 120 kg live weight
Authors: Chadd S. A. , Cole D. J. A. , Walters J. R. 
Published: August 2016

AbstractUsing a completely randomized design, 72 individually penned pigs, comprising two genotypes (Masterbreeders Mastergilt × Large White and Sovereign × Large white progeny) with equal numbers of boars and gilts, were given foodad libitumfrom 25 to 60 kg live weight. From 60 to 120 kg one-third of the pigs continued to be given foodad libitumwhilst the remainder were given one of two levels of restriction (0.85 and 0.925 of maintenance energy × 3.5). Diets were calculated to provide 13.8 and 13.0 MJ digestible energy (DE) per kg air-dry weight for growing and finishing phases respectively. Ultrasonic measurements of backfat at the P2 site were made at 10 kg intervals from 60 to 120 kg live weight and carcass measurements taken at slaughter. Complete dissection of ham joints was carried out. Predictedad libitumintakes were based on established equations but daily intakes were much lower than these values and no treatment provided food restriction compared with them. Daily DE intakes (mean of both genotypes) obtained at 25, 60, 90 and 120 kg live weight were 204, 30.7, 36.2, and 414 MJ (i.e. 3.5, 3.1, 2.9 and 2.7 × maintenance). During the growing (25 to 60 kg live weight) and finishing (60 to 120 kg live weight) periods boars grew faster (P&lt; 0.01 andP&lt; 0.001) than gilts (881v.827 and 944v.806 g/day) with corresponding improvements in food conversion ratio (P&lt; 0.001). Boars had lower killing-out proportions (0.787v.0.801;P&lt; 0.001). Mean P2 values for boars and gilts were 13.2 and 13.9 mm respectively (excluding skin). Greater quantities of muscle were found in the hams of boars than gilts (662.7v.642.3 kg;P&lt; 0.05) but no difference between the sexes for ‘eye muscle’ area was observed (43.3v.45.0 cm2). Results show the apparent potential of modern hybrids to achieve good growth rates despite moderate food intakes and their ability, even when given continuous access to food, to produce very lean carcasses at relatively heavy slaughter weights.
Nutritional effects on ovulation, embryo development and the establishment of pregnancy in ruminants
Authors: O’Callaghan D. , Boland M. P. 
Published: August 2016

AbstractThe effects of high and low dietary dietary intake on reproduction in female cattle and sheep will be considered at the level of the pituitary gland, ovary and uterus. In sheep, increased dietary intake for a relatively short time will increase ovulation rate, by increasing gonadotropin secretion. Dietary intake can affect steroids such as progesterone and also intra-follicular concentrations of some growth factors such as IGF-1 and IGF-2. The effects of altered energy intake on gonadotropins and steroids in cattle are not as repeatable as those in sheep but follicular growth rates can be altered. High nutrition has a negative effect on oocyte quality, with animals onad-libitumhigh energy diets particularly at risk. Overfeeding can decrease embryo quality in both sheep and cattle and it appears that this results from changes primarily at the level of the follicle or oocyte. Restricted nutrition for a short time will enhance pregnancy rates in cattle; most of this benefit appears to occur if food is restricted before insemination. Thus feeding levels before mating are particularly important to subsequent reproductive success. High dietary crude protein may decrease pregnancy rate in lactating cows. In ewes and heifers supplementation with urea failed to have any effect on pregnancy rates when good quality embryos were transferred to recipient animals exposed to high dietary crude protein. In donor ewes there were adverse effects on early embryo development following urea treatment, suggesting that the mechanism affecting the reproductive process was primarily operating at the level of the oocyte. Collectively, these data identify the overall deleterious effects of high dietary intake and excess crude protein on fertility and highlight the importance of dietary intake before ovulation on the likelihood of establishing a viable pregnancy.
The potential for identifying heritable endocrine parameters associated with fertility in post-partum dairy cows
Authors: Darwash A. O. , Lamming G. E. , Woolliams J. A. 
Published: August 2016

AbstractFertility is an important component of herd production efficiency, as each additional oestrous cycle that does not result in a planned pregnancy adds to the cost of dairy farming. In addition to the negative impact on milk production, the high costs of veterinary intervention, re-insemination and herd replacement, subfertility can affect the rate of genetic gain in traits of economic merit. In contrast with the steady increase in average milk yield per cow during the last 30 years, there has been a decline in conception rate to artificial insemination in both the USA and in the UK.The genetic correlation between yield and fertility has been equivocal. Attempts to improve the reproductive efficiency in dairy cattle through breeding and selection have been frustrated to date by the lack of heritable reproductive parameters conducive to high fertility. However, the traditional fertility parameters of interval to first service, services per conception, days open and calving intervals are highly influenced by managerial decisions and have, as expected, heritabilities too low to permit a meaningful genetic gain through selection. An alternative approach is to use the growing body of evidence that the majority of endocrine factors affecting reproduction are a result of gene expression at the hypothalamic, pituitary, ovarian or uterine level. Mechanisms such as commencement of post-partum cyclicity, follicle wave patterns, manifestation of oestrus, luteal competence and level of embryo mortality are appropriate for study. Research is required to investigate the genetic component of the variation between animals in these parameters, their phenotypic and genetic correlations with fertility and their association with other production traits.In summary: (a) subfertility is a syndrome with multiple causes and only the symptom in common; (b) improvement in fertility will continue to be frustrated until recorded traits provide more accurate estimates of breeding values; (c) techniques are now available to estimate the genetic variation in physiological components conducive to improved reproductive efficiency; (d) once the heritable components of fertility are identified, these tools could be introduced into progeny testing and breeding nuclei, from which the genetic improvement can be widely disseminated. Selection for those components with sufficient genetic variation will result in the improvement of the integral endocrine and other physiological mechanisms favourably correlated with high fertility (e) these tools may also assist in detecting quantitative trait loci for faster genetic gain through markers-assisted selection.
Effect of feeding level during rearing and mating strategy on performance of Swedish Yorkshire sows. 2. Reproductive performance, food intake, backfat changes and culling rate during the first two parities
Authors: Cozier Y. Le , Ringmar-Cederberg E. , Rydhmer L. , Lundeheim N. , Dourmad J. Y. , Neil M. 
Published: August 2016

AbstractA 2 x 2 factorial experiment was designed in order to study the effects of feeding level during rearing and of mating policy on the reproductive performance and food intake of first- and second-litter sows. Gilts were offered food during rearing eitherad libitum(AL) or at 0·8 of the AL level (R) and served either at first (E1) or third (E3) detected oestrus. A total of 160 out of the 243 animals that started the experiment were culled by the end of the second lactation, with significantly more R than AL animals (71 and 60%, respectively). During the first pregnancy, the R sows gained more live weight (LW) and backfat thickness (BF) than their AL contemporaries (+5 kg and +1.2 mm, respectively) and lost less BF during the first lactation (1.2 mm less). At weaning, no difference remained in LW or BF between AL and R sows (174 kg LW on average). The E3 females gained less LW during both pregnancies compared with those on the E1 treatment, but they remained heavier until the second weaning (208 kg, on average). During the first lactation, R consumed more food during the weeks 2 and 3 (by 0·5 kg/day, on average) than those reared previously on the AL regime, and no difference was observed between E3 and E1 females. No difference in food consumption was noted during parity two. However, when measured over the first two parities, lean animals consumed more food than fat animals. The size and the weight of the litter at birth or at weaning were not influenced by the treatment prior to service. The weaning-to-oestrus interval was longer during parity one than during parity two (5·7 and 5·0 days, respectively;P< 0·01) but it was not affected by feeding or mating treatment.
Endogenous ileal nitrogen and amino acid flows in the growing pig receiving a protein-free diet and diets containing enzymically hydrolysed casein or graded levels of meat and bone meal
Authors: Donkoh A. , Moughan P. J. 
Published: August 2016

AbstractEndogenous ileal amino acid flows were determined in pigs fitted with simple T-cannulas using either the regression method (meat and bone meal (MBM) as the protein source at five levels of inclusion) or following protein-free alimentation. Amino acid flows were compared with those determined by feeding animals a diet the sole nitrogen source of which was enzyme-hydrolysed casein (EHC), followed by centrifugation and ultrafiltration of the ileal digesta. The EHC was a mixture of free amino acids and oligopeptides (molecular weight 5000 Da). For the EHC treatment, the ileal digesta precipitate plus retentate was used to determine the endogenous flows. The ultrafiltration step excludes unabsorbed dietary amino acids from the measure of endogenous loss. Chromium III oxide was the reference marker in all diets. Estimates of endogenous nitrogen and amino acid flows determined under protein-free alimentation and the comparable flows determined using the regression method were similar. However, endogenous flows of amino acids for the EHC-fed pigs were generally significantly higher (F < 0·01) than values found for pigs on the protein-free diet and were higher than values obtained after extrapolation for pigs given the MBM-based diets. Mean endogenous ileal nitrogen flow for the EHC-fed animals was 2526 (s.e. 33.9) compared with 1711 (s.e. 25.5) mg/kg dry-matter intake for pigs receiving the protein-free diet.
Changes in fibre traits in Scottish Cashmere and Siberian goat kids and their relationships with annual production and diameter of the undercoat
Authors: Merchant M. , Riach D. J. 
Published: August 2016

AbstractThe pattern of follicle activity and fibre growth on the neck, mid side and rear leg of 12 Scottish Cashmere (SC) and nine Siberian (S) goat kids was examined from birth to 255 days of age. In both genotypes maximum secondary to primary follicle (S/P) ratio was reached earliest on the neck (P < 0·05) but was proportionately 0·21 and 0·28 (P < 0·001) lower than that on the rear leg and mid side respectively. Secondary follicle activity ceased earlier on the rear leg than the mid side or neck (P < 0·001) and this was associated with lower staple lengths and patch weights of undercoat. Fibre weight and diameter were compared on six body parts: neck, front leg, mid side, rear leg, rump and belly at 255 days of age. Patch undercoat weights and diameter were greatest on the neck, front leg and rump and lowest on the belly.The estimated annual production of undercoat, calculated from patch weights and skin area measurements on the six parts of the body at 255 days of age was 138 (range 42 to 260) g for SC kids and 525 (range 377 to 661) g for S kids (s.e.d. = 39·4, P < 0·001). Mean undercoat diameter was 16·15 (range 15·32 to 17·51) and 18·94 (range 17·25 to 19·89) μm for SC and S kids respectively (s.e.d. = 0·376, P < 0·001).Correlation coefficients between fibre traits, measured at approximately monthly intervals and estimates of annual production and undercoat diameter at 255 days were calculated. For SC kids mid-side patch undercoat weight was consistently and strongly related to estimated annual production (mean correlation coefficient, 0·85, s.e. 0·036). For S kids the only variable to show a consistently strong relationship with estimated annual production was mid-side undercoat staple length × diameter2 (mean correlation coefficient 0·66, s.e. 0·067). Thus the best fibre traits for ranking annual production differed between genotypes. In both cases the accuracy of the ranking increased with age. Undercoat fibre diameter measured from 4 to 5 months of age was closely related to estimated undercoat diameter at 255 days of age in both SC and S genotypes (mean correlation coefficient 0·92, s.e. 0·009). Prior to 4 months of age the mean correlation coefficient for SC and S genotypes was 0·53 (s.e. 0·20).It is concluded that goat kids can be ranked for annual production and diameter of the undercoat, prior to first harvesting, based on fibre traits measured on samples of the fleece.
The influence of drinker allocation and group size on the drinking behaviour, welfare and production of growing pigs
Authors: Turner S. P. , Edwards S. A. , Bland V. C. 
Published: August 2016

AbstractCurrent Welfare Code recommendations suggest one nipple drinker per 10 pigs, while farmers have often used a ratio of one per 20 animals. This statement is based on information from pig farmers and advisors in the United Kingdom. Neither approach is based on empirical investigation. The use of larger group sizes in commercial herds raises further questions, since the relationship between group size and the appropriate number of drinking points cannot be assumed to be linear. The aim was to assess the two conflicting drinker allocations for their effect on welfare, as measured by drinking behaviour, social behaviour and performance, and any effect of group size on these. A total of 640 Large White × Landrace growing pigs were assigned to four treatments in a 2 × 2 factorial arrangement (60 pigs, three drinkers; 20 pigs, one drinker; 60 pigs, six drinkers and 20 pigs, two drinkers). Drinker provision had no significant effect on water use (5.10, 3.88, 4.99 and 3.45 s.e. 0.231 I per pig per day respectively) but in a larger group more water was used in less drinking time (P < 0.001). The diurnal pattern of water use was similar for each treatment. More aggression occurred at the drinker in large groups with a poorer drinker allocation (11.0 v. 3.8% of drinking bouts terminated by aggression for 60 pigs with three drinkers and mean all other treatments respectively, P < 0·05). Overt aggression (2.22, 2.27, 1.76 and 2.07 (s.e. 0.284) aggressive acts per pig per h, respectively) and lesion score counts of a sample of pigs from each pen suggested no difference between treatments. Providing one drinker per 20 animals, even in a large group, did not affect drinking behaviour, social behaviour or production. These findings should not be extrapolated to situations of different ambient temperature, water flow rate or feeding strategy.