bluuebunny/crossref_metadata_2025_split huggingface dataset:
MOET results from a dispersed hybrid nucleus programme in dairy cattle
Authors: Lohuis M. M. , Smith C. , Dekkers J. C. M. 
Published: August 2016

AbstractA dispersed hybrid MOET nucleus project was implemented in the Canadian dairy industry. Embryo yield, pregnancy rate, and effects of management and selection practices are reported. Repeatability of viable embryo yield was 0.31. Average viable embryo yield was 6.85 (s.e. 5.35) embryos per collection, with average pregnancy rates of 0.58, 0.46 and 0.51 for grade 1 fresh, frozen, and split embryos, respectively. Of the donors selected, 80% produced enough embryos to form a family of at least 15 offspring. Based on observed results, expectations of family size and structure and generation intervals were calculated. Only 10% of completed families are expected to result in less than three milking daughters. Generation interval for sib-tested sires was 58 months of age under practical field conditions, which was shorter by a factor of 0.19 than a traditional progeny test but longer than original theoretical estimates by a factor of 0.32. Realized selection intensities for a total merit index were 2.22 for sires and 3.77 for dams of embryos. Accuracies of selection for sires and dams were 0.93 and 0.73 respectively. To improve the scheme, use of more fresh embryos, embryo splitting and less delay in transferring frozen embryos are recommended.
Comparison of the simple breeding value model and the maternal effects model for genetic evaluation of Segureña lambs
Authors: Analla M. , Muñoz-Serrano A. , Serradilla J. M. 
Published: August 2016

AbstractWeaning weight in a single flock of 600 ewes and 40 rams was simulated through 30 consecutive lambings. The objective was to compare the simple breeding value model with the maternal effects model for lamb evaluation under the Segureña selection scheme. Three selection strategies were tested: selection on breeding values estimated by a simple breeding value model that ignores maternal effects (method 1), selection on direct additive values only (method 2) or on the sum of direct and maternal additive values (method 3), both latter methods utilizing a maternal effects model. Average values obtained in the last lamb crop were about 18 kg for the phenotypic mean, about 5 kg for direct additive values and about -1 kg for maternal additive values, for all three methods. Average inbreeding coefficient of the last crop was more than 0·13 in method 1 but was less than 0·12 in the others. All differences were not statistically significant (P > 0·05). Consequently, the simple breeding value model can be used for the genetic evaluation of weaning weight of candidates for selection in the Segureña scheme. The effect of variation in the magnitude of parameters was evaluated through four sets of parameters. Results showed that with a higher additive maternal component, method (3) would become increasingly necessary. The need for method (3) is accentuated with more negative additive covariance between direct and maternal effects. Thus, for higher maternal effects or more negative additive correlation, the use of the complete model (with maternal effects) becomes unavoidable. Varying population size, however, affects only the inbreeding accumulated, as long as the same methods of selection are used.
The inheritance of wool quantity and live weight in the French Angora rabbit
Authors: Allain D. , Rochambeau H. de , Thébault R. G. , Vrillon J. L. 
Published: August 2016

AbstractMore accurate definition of Angora rabbit breeding objectives has been investigated by considering multiple expression of different traits. Data on 9672 fleece harvests produced by 1343 Angora does which had at least one wool harvest were analysed in order to study genetic variability according to age. The animals of the French breed were defleeced and weighed at 8 and 21 weeks of age for the first and second time respectively. Thereafter, does were defleeced every 14 weeks and weighed 9 weeks before defleecing. Total fleece weight and live body weight were recorded at each harvest.Direct heritability estimates of total fleece weight were similar accross ages and ranged from 0·31 to 0·42 . A significant maternal heritability was also observed at all ages of harvest. Maternal genetic estimates decreased with age from 0·44 at the first harvest to 0·10 for an adult harvest. Except for 8 weeks of age, genetic correlations between total fleece weight and live weight were generally not significantly different from zero. Genetic correlations of total fleece weight between the first and subsequent harvests were low (from 0·22 to 0·39) but genetic correlation estimates between consecutive harvests after the first were high, and ranged from 0·68 to 0·89 . The results suggest that the second harvest would be the first good predictor of breeding value for total fleece weight in the adult Angora rabbit.
The influence of rate of lean and fat tissue development on pork eating quality
Authors: Blanchard P. J. , Ellis M. , Warkup C. C. , Hardy B. , Chadwick J. P. , Deans G. A. 
Published: August 2016

AbstractThe influence of plane of nutrition and diet on the eating quality of fresh pork was investigated in a study involving 721 animals. Boars and gilts of three genotypes (0, 0·25 and 0·50 Duroc inclusion level) were reared from 30 to 90 kg on seven feeding regimens (combinations of diet formulation and feeding level) to achieve different rates of lean and fat tissue growth during two growth periods (30 to 60 or 75 kg; 60 or 75 kg to 90 kg), respectively. A diet of conventional energy and protein (CEP, 14·2 MJ/kg digestible energy, 205 g/kg crude protein, 10 g/kg lysine) was given using combinations of ad libitum and restricted feeding to produce six treatment groups with variation in lean and fat growth rates. An additional treatment group was given food ad libitum on a higher energy and lower protein diet (HELP, 14·7 MJ/kg digestible energy, 166 g/kg crude protein, 7·0 g/kg lysine) between 30 and 90 kg. Dissected carcass composition at 90 kg was predicted from equations based on P2 fat depth, which were developed from full-side and ham joint dissections on sub-samples of animals. Representative sub-samples of animals were dissected at start (30 kg) and at interim weights (60 or 75 kg) to allow lean and subcutaneous fat growth rates to be calculated for all or parts of the growth period. The feeding regimes produced substantial variation in live-weight gain (DLWG) (744 to 914 g/day) and lean tissue growth rate (LTGR 345 to 417 g/day) and subcutaneous fat growth rate (SFGR 81 to 97 g/day), between 30 and 90 kg, and in longissimus dorsi intramuscular fat content (10·37 to 23·87 g/kg). Pigs given the HELP diet had the highest intramuscular fat and the best eating quality. Pigs offered the CEP diet ad libitum throughout the growth period produced more tender but less juicy meat than those given food restrictedly (0·8 or 0·9 of ad libitum). The correlations between DLWG, LTGR and SFGR for the whole or parts of the growth period and sensory characteristics, although often positive, were generally low, suggesting weak relationships.
The effects of retrogradation and amylose/amylopectin ratio of starches on carbohydrate fermentation and microbial populations in the porcine colon
Authors: Reid C.-A. , Hillman K. 
Published: August 2016

AbstractThe colon of the simple-stomached animal comprises a gradually changing microbial environment, using the residues of digestion as substrates for fermentation. As carbohydrate sources decline along the length of the colon, the microflora degrade proteins to use as an energy supply, resulting in the formation of undesirable and potentially toxic metabolites. This study has examined the possibility of using dietary starches as a means of extending carbohydrate fermentation along the colon in order to reduce the effects of protein degradation, and the influence of these starches on the numbers of microbial groups within the total population. The study was carried out in weaned piglets, using native and retrograded forms of maize and waxy maize starches, containing proportionately about 0·25 and 0·01 amylose respectively. It was found that protein degradation in the mid and distal regions of the colon was best reduced by the inclusion of the retrograded form of waxy maize, although these data did not achieve significance. However, it was found that a reduced population of the protein-degrading Bacteroides spp. resulted from the inclusion of waxy maize rather than maize in the diets, (proximal colonP< 0·01 ; mid colonP< 0·001 , distal colonP< 0·05), while the retrograded waxy maize produced increased lactobacillixoliform ratios throughout the colon, which may result in an improved resistance to infection by intestinal pathogens. Retrogradation of these starches reduced the coliform populations throughout the colon, with significant (P< 0·05) effects observed in the proximal and distal regions. The data suggest that, of the starches tested, reduced protein-degrading activity and improved pathogen resistance may be achieved with retrograded waxy maize.
The effects of raising post-oestrus progesterone concentrations on luteal activity in post-partum dairy cows
Authors: Darwash A. O. , Ward G. L. , Lamming G. E. , Woolliams J. A. 
Published: August 2016

AbstractIn order to investigate the rationale of manipulating post-ovulation progesterone (P4) concentrations, luteal activity was measured in 10 Holstein-Friesian cows treated with a progesterone-releasing device (CIDR, 1·9 g P4) inserted on the morning of day 2 post-oestrus for a period of 7 days and compared with 10 untreated control animals. Milk samples were collected daily during afternoon milking from 7 days pre- to 24 days post-oestrus and P4 concentrations were measured using enzyme-linked immuno-sorbent assay (ELISA). The milk P4 profiles were used to assess the effects of early post-oestrus P4 elevation on five intervals of the luteal phase. In the treated (T) and control (C) animals, the mean interval from oestrus to P4 rise (≥3 μg/l), was 2·38 (s.e. 0·18) and 4·90 (s.e. 0·28) days, respectively, (P < 0·01). The mean interval from oestrus to the attainment of peak P4 concentrations was not significantly different (P > 0·05) between the T (14·75 (s.e. 1-62) days) and С (14·30 (s.e. 0·70) days) animals, with cows in the T group showing a more variable (F7 9 = 4-30, P < 0·05) interval to the occurrence of the peak. The interval from peak P4 to corpus luteum (CL) regression (when P4 fell below ≥3 μg/l) was not significantly different between the T (4·13 (s.e. 1·30 days) and С (5·60 (s.e. 0·88) days) groups. Furthermore, CIDR insertion did not alter luteal phase length, number of days with P4 concentrations ≥3 μg/l (T = 16·50 (s.e. 0·80) v.C = 15·00 (s.e. 0·47) days) or the interval from oestrus to CL regression (T = 18·88 (s.e. 0·79) v.C = 19·90 (s.e. 0·41) days). We conclude that treatment with CIDR 2 days after oestrus successfully increased the availability of P4 to cows without significantly affecting luteal phase characteristics.
Effect of dietary forage: concentrate ratio on the behaviour, rumen fermentation and circulating concentrations of IGF-1, insulin, glucagon and metabolites of beef steers and their potential effects on carcass composition
Authors: Thorp C. L. , G.Wylie A. R. , Steen R. W. J. , Shaw C. , McEvoy J. D. 
Published: August 2016

AbstractIn an investigation of factors responsible for the lower efficiency of carcass lean gain seen previously in steers offered grass silage diets 18 Simmental × British Friesian steers (361 (s.e. 5-35) kg) were offered one of three diets: a perennial ryegrass silage ad libitum and alone (S) or supplemented with rolled barley at 300 g/kg of total dry matter (SC) or supplemented as described but restricted (SCr) in quantity so as to provide the same dry matter (DM) and digestible energy (DE) intakes as for S. Eating (Eb), ruminating (Rb), standing (Sb) or lying (Lb) behaviour was quantified during four 24-h periods of manual observation. Eb was noted in more detail in a second experiment using computerized Calan-Broadbent gates and load cells to monitor times and rates of eating. Blood was taken via temporary indwelling jugular catheters at 30 to 60 min intervals on each of 4 days 1 month apart. Rumen fluid was sampled hourly for three 24-h periods from three rumen-cannulated steers given the same three diets in a separate 3 x 3 change-over design experiment.Steers offered the restricted diet SCr ate most of their food in one extended meal within 6 h of feeding while two peak eating periods (morning and evening) were observed in steers offered the other two diets. Steers offered SCr spent more time in Sb (P < 0.05), and less time in Eb (P < 0·001) and Rb (P < 0·05) activities than did animals offered the two diets ad libitum (SC and S). Mean 24 h insulin-like growth factor-1 (IGF-1) concentrations and postprandial insulin concentrations were significantly higher with diet SCr than with diet S (P < 0·001) despite equal daily DM and DE intakes from each. Insulin appearance in the jugular vein reflected the pattern of food intake on all treatments. Rumen fermentation characteristics were largely unaffected by diet. Mean 24 h rumen volatile fatty acid, pH and ammonia concentrations did not differ between diets but post-prandial rumen pH tended to be lower in animals offered the SC and SCr diets.Differences in patterns of food intake between animals offered food ad libitum and at a restricted level are likely to determine patterns of nutrient absorption and the secretion of nutritionally regulated splanchnic hormones. The higher proportions of Sb and Rb activities in steers offered the restricted diet represent an energy cost to these animals while the higher plasma IGF-1 and insulin concentrations also seen in these animals may collectively influence the partitioning of nutrients to the peripheral tissues and contribute to the increased efficiency of carcass lean deposition previously shown in animals offered such diets.
Coypu (Myocastor coypus) as a meat resource: heterotic and maternal effects on growth traits
Authors: Spiaggi E. P. , Benaglia A. , Di Masso R. J. 
Published: August 2016

AbstractThe coypu (Myocastor coypus) is an aquatic rodent usually bred for fur production. Fluctuations in fur prices have led to coypu meat being considered as a genuine resource in commercial farms, which contribute to the diversification of agro-ecosystems. To characterize coypus as a meat resource, maternal and heterotic effects on birth weight, weaning weight, slaughter weight, number of days required to attain a weaning weight of l kg, and on two parameters of the Gompertz growth curve (asymptotic weight and maturing rate) were studied. Eight males and eight females of Standard (S) and Cognac (C) genotypes and of their reciprocal crosses (C × S) and (S × C), where the first letter denotes the paternal genotype, were used. Significant genotype, sex and (genotype × sex) interaction effects were evident for most traits. S animals were lighter than С at all ages. Hybrids with С mothers were heavier than their reciprocals. Maternal effects on the parameters of the growth curve were observed only in females. Heterotic effects were extremely significant. Favourable heterotic effects in immature animals were explained by a change in the F1 growth pattern. Males showed a dominant deviation toward low asymptotic weights and overdominance for high maturing rate. Females showed partial dominance of high asymptotic weight and over dominance for high maturing rate. This association of genetic effects would justify a productive system based on a terminal cross using С females and S males because of the higher maturing rate of both hybrids and the maternal effect of С genotype, a combination that allows higher weights at the usual slaughter age (6 months) or butchering of animals at earlier ages.
Choice of probing site for classification of live pigs using ultrasonic measurements
Authors: Hulsegge B. , Mateman G. , Merkus G. S. M. , Walstra P. 
Published: August 2016

AbstractBody length and ultrasonic fat thickness measurements were taken on 86 live pigs in order to find an optimal probing site for estimation of lean meat proportion. The next day pigs were slaughtered and measurements with the Hennessy Grading Probe (HGP) were made in order to estimate the lean meat proportion.Fat thickness, 6 cm off the dorsal mid line, increased from a value of 9·5 mm at a site 4 cm cranial to the last rib, progressively through intermediate sites to a value of 12·4 mm, 22 cm cranial to the last rib. Fat thickness measurements at different sites (live pigs) were highly correlated with HGP fat thickness at the site between 3rd and 4th from last rib (3/4 LR) and estimated lean meat proportion (carcasses); correlations ranged from 0.80 to 0.89 and -071 to -0.85 respectively. The most accurate predictor of estimated lean meat proportion from the live pig measurements was the measurement at 18 cm cranial to the last rib. Measurement at the site half the distance between the occipital bone and the base of the tail (midpoint) was the second-best for estimated lean meat proportion.Generally, this midpoint on live pigs was situated around the 3/4 LR on carcasses. However, the range was considerable. Half of the number of animals had a midpoint in the range of -2.5 to 2.5 cm from 3/4 LR. The site midpoint is easily located on the animal and the results of this study suggest that it can be used as an accurate predictor of estimated lean meat proportion. Therefore it can serve as the probing site for classification of live pigs.
The effect of changing patterns of fertilizer applications on the major
mineral composition of herbage in relation to the requirements of cattle: a
50-year review
Authors: Hemingway R. G. 
Published: August 2016

Abstract
Annual surveys of fertilizer practice have been conducted since 1942. Since
1985, nitrogen application rates to grass have progressively declined and
phosphorus application has been reduced since the mid 1970s. Increasing
environmental issues and the present interest in organic farming and low input
systems indicate that these trends will continue. Present overall fertilizer use
for grazing on dairy farms is about 170 kg N, 10 kg P and 20 kg К per ha. Higher
rates are used for intensive silage production, 200 kg N, 15 kg P and 50 kg К per
ha. In contrast, recommended applications are 340 kg N, 18 kg P and 25 kg К per ha
for grazing and 380 kg N, 40 kg P and 260 kg К per ha for intensive silage.
Herbage yield is controlled by the amount and timing of nitrogen fertilizer
applications. The major mineral content depends on herbage maturity within the
growth cycle; both phosphorus and potassium contents fall with declining crude
protein concentrations.
Nitrogen fertilizer generally increases both magnesium and sodium
concentration whilst potassium application decreases both. The overall effect of
combined applications is to minimize changes. In the critical spring and autumn
periods, herbage dry-matter intakes may be as important as magnesium content and
availability when assessing the risk of hypomagnesaemia in the grazing
cow.
Fertilizers, including phosphorus, even in the long term, have little effect
on the calcium and phosphorus contents of herbage. Nitrogen and phosphorus
concentrations are significantly ocrrelated in grazed herbage, silage and hay. If
environmental or economic policies were to result in a reduction in the crude
protein content of grazed herbage from ca. 250 to ca. 200 g/kg dry matter, the
phosphorus intake of a cow giving 30 kg milk per day would fall by 0·5 g/kg
dry-matter intake. This, together with any desirable additional magnesium, should
preferably be given as an oral mineral supplement rather than by attempting to
modify the mineral content of herbage.
Seasonal changes of metabolism and appetite in Soay rams
Authors: Argot C. McG. , Smith J. S. , Kay R. N. B. 
Published: August 2016

Abstract
Relationships between photoperiod and cycles of voluntary food intake (VFI)
and maintenance energy requirements (MER) were determined in Soay rams, subjected
to a 6-month photoperiodic regime. Food was offered ad
libitum (no. = 5) or at a predicted maintenance level (no. = 5).
All rams demonstrated 6-month cycles of VFI, growth and reproductive status.
Metabolizable energy intake (MEI) was greatest in rams given food ad
libitum (666 (s.e. 21.7) kJ/kg metabolic live weight
(M0·75) and food-restricted (528 (s.e. 12.2) kJ/kg
M0·75) rams during sexual quiescence. Conversely, MEI was
minimal (ad libitum, 289 (s.e. 8.4) kJ/kg
M0·75; restricted, 428 (s.e. 8.1) kJ/kg
M0·75) during the rut. Distinct cycles of heat production
(HP) accompanied changes in MEL Changes in HP were similar (P > 0·05) for both
groups (ad libitum, 520 (s.e. 22.1) to 394 (s.e. 9.2)
kJ/kg M0·75; restricted 503 (s.e. 14.0) to 407 (s.e. 17.5)
kJ/kg M0·75) and therefore energy retention varied more (P
< 0·015) when rams were given food ad libitum
(ad libitum, 131 (s.e. 43-1) to -106 (s.e. 38.2)
kJ/kg M0·75; restricted, 78·0 (s.e. 27.1) to -53.0 (s.e.
38.2) kJ/ kg M0·75). Apparent digestibility of dietary energy
varied inversely with MEI (P < 0·01). MERs ranged from 524 (s.e. 35.0) kJ/kg
M0·75 to 401 (s.e. 27.3) kJ/kg M0·75,
a proportional fluctuation of ±0·13. Changes in metabolic rate preceded those in
appetite, suggesting a causal relationship.
Carcass quality of crossbred lambs expressing the callipyge phenotype born to Romanov purebred and crossbred ewes
Authors: Fahmy M. H. , Gariepy C. , Fortin J. 
Published: August 2016

AbstractCarcass quality was evaluated in 35 male and 41 female lambs, 38 expressing the callipyge phenotype (Cg) and 38 controls expressing the normal phenotype (N). Lambs were from Romanov and Suffolk × Romanov ewes mated to two rams heterozygous for the callipyge locus and slaughtered at approximately 44 kg live weight. The Cg lambs reached slaughter weight at 163 days of age, 13 days younger, and had a dressing proportion 0·524 , 0·029 points higher. Also they had more leg (341 v. 308 g/kg), less loin (315 v. 328 g/kg) and less shoulder (340 v. 360 g/kg) than the N lambs. The leg, loin and shoulder wholesale cuts and half the carcass of Cg lambs had 81, 113, 77, and 92 g/kg more lean and 52, 98, 59, and 72 g/kg less fat than N lambs, respectively. The Cg lambs also had larger loin-eye area (18·5 v.13·1 cm2), less backfat at the C (4·1 v. 6·1 mm) and at the GR locations (11·0 v. 15·2 mm) and less internal fat (202 v. 339 g) than the N lambs. Dissection of the 12th rib indicated that Cg lambs had more muscle (574 v. 462 g/kg), less fat (276 v. 358 g/kg) (both P < 0·001) and similar (V > 0·05) bone (155 v. 265 g/kg) to N lambs. Colour of the longissimus muscle was significantly paler in Cg lambs. Intramuscular fat and dry matter of longissimus muscle were significantly lower (49 v. 120 and 247 v. 253 g/kg) in Cg than in N lambs. Cg lambs were significantly different (P < 0·05) from N lambs for all traits studied except age at slaughter, tissues at the GR location, proportion of bone in the 12th rib and the L* colour of the longissimus muscle. Breed type effect was significant only for age at slaughter, whereas the effect of sex was significant for all traits except for proportion of lean in the leg, b* colour and intramuscular fat content of the longissimus muscle. No interactions were significant except phenotype × breed type on fat thickness over the longissimus muscle. Post-mortem ageing of the longissimus muscle for 9 or 15 days caused a significant reduction in muscle toughness in Cg lambs compared with those aged for 3 days (113 v. 98 Newtons) but the muscle was still tougher than that from N lambs (with a shear force of 64 and 51 Newtons at 3 and 9 or 15 days post mortem). The principle component analysis including carcass conformation and composition traits as well as meat quality traits was indicative of a distinctly different carcass ofCg compared with N lambs. The first two principal components explained 0·70 of the total variation.