bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection of quantitative trait loci for locomotion and osteochondrosis-related traits in Large White ✕ Meishan pigs
Authors: Lee G.J. , Archibald A.L. , Garth G.B. , Law A.S. , Nicholson D. , Barr A. , Haley C.S. 
Published: May 2019

AbstractData from the F2generation of a Large White (LW) ✕ Meishan (MS) crossbred population were analysed to detect quantitative trait loci (QTL) for leg and gait scores, osteochondrosis and physis scores. Legs, feet and gait score were assessed in 308 F2animals at 85 ( + 5) kg and osteochondrosis and physis scores were recorded for the right foreleg after slaughter. A genome scan was performed using 111 genetic markers chosen to span the genome that were genotyped on the F2animals and their F1parents and purebred grandparents. A QTL on chromosome 1 affecting gait score was significant at the genome-wide significance level. Additional QTL significant at the chromosome-wide 5% threshold level (approx. equivalent to the genome-wide suggestive level) were detected on chromosome 1 for front feet and back legs scores, on chromosome 13 for front legs and front feet scores, on chromosome 14 for front legs, front feet and back legs scores and on chromosome 15 for back feet score. None of the QTL for osteochondrosis score exceeded the chromosome-wide suggestive level, but one chromosome-wide QTL for physis score was found on chromosome 7. On chromosome 1, gait and front feet scores mapped to the middle of the chromosome and showed additive effects in favour of the LW alleles and no dominance effects. The QTL for back legs score mapped to the distal end of the chromosome and showed a dominant effect and no additive effect. On chromosomes 14 and 15, the LW allele was again superior to the MS allele. On chromosome 13, there were both additive and dominance effects in favour of the MS allele. The MS alleles on chromosome 13 may have potential for introgression into a commercial LW population. The other putative QTLs identified may have value in marker-assisted selection in LW or MS-synthetic populations.
Sensitivity to dietary lysine: energy content in pigs divergently selected for components of efficient lean growth rate
Authors: Cameron N.D. , Garth G.B. , Penman J.C. , Fiskin A. 
Published: May 2019

AbstractThe sensitivity to dietary lysine: energy content of pigs from lines divergently selected over seven generations for components of efficient lean growth rate was quantified by the within-selection line regression of performance test traits on diet class. Large White pigs were performance tested over three 14-day test-periods starting at 30, 50 and 75 kg and offered, to appetite, isoenergetic diets differing in dietary total lysine: energy (0•59, 0•69, 0•81, 0•91, 1•01, 1•12 and 1•23 g/MJ digestible energy (DE)). Within each litter, full-sibs were performance tested on different diets. Pigs were also performance tested on a diet-choice procedure using diets with total lysine: energy of 0•69 and 1•12 g/MJ DE to determine the correlation between performance on phase-feeding and diet-choice.The study consisted of 578 animals with 459 pigs tested with phase-feeding and 119 tested on diet-choice procedures. The study detected significant selection line and dietary effects on performance test traits, but no significant between-selection line differences in sensitivity to dietary total lysine: energy. When combinations of performance test traits were transformed into predicted lysine and energy utilization traits there were significant selection line effects on predicted nutrient allocation, but not in responses to increasing dietary total lysine: energy. The lack of between-selection line differences in sensitivity to dietary total lysine: energy indicated that the consequences of changing dietary total lysine: energy will be broadly similar across a range of genotypes, as spanned by the selection lines of the study.Genetic correlations between performance traits of phase-fed and diet-choice pigs suggested that predictions of genetic merit will be similar with animals tested on either procedure between 30 and 75 kg but post 75 kg predicted genetic merit for growth rate and lysine intake should be estimated separately for performance on diet-choice or for performance on a given diet. In contrast, predicted genetic merit for fat deposition with performance testing on diet-choice will be highly correlated with predicted genetic merit with testing on a single diet.
Accuracy of prediction of percentage lean meat and authorization of carcass measurement instruments: adverse effects of incorrect sampling of carcasses in pig classification
Authors: Engel B. , Buist W.G. , Walstra P. , Olsen E. , Daumas G. 
Published: May 2019

AbstractClassification of pig carcasses in the European Community is based on the lean meat percentage of the carcass. The lean meat percentage is predicted from instrumental carcass measurements, such as fat and muscle depth measurements, obtained in the slaughter-line. The prediction formula employed is derived from the data of a dissection experiment and has to meet requirements for authorization as put down in EC regulations. Requirements involve the sampling procedure and sample size for the dissected carcasses and the accuracy of prediction. Formulae are often derived by linear regression. In this paper we look at a particular type of sampling scheme. This involves selection of carcasses on the basis of carcass measurements not all of which are intended to be used as prediction variables. This sampling scheme frequently appears in requests for authorization of carcass measurement instruments and accompanying prediction formulae, despite the fact that it lacks formal statistical justification when used in conjunction with linear regression. The objective of this work was to assess the performance of the prediction formula that follows from this potentially faulty combination of sampling scheme and linear regression in relation to the requirements in the EC regulations. We show that this sampling scheme may produce poor predictions for lean meat percentage compared with proper sampling procedures with selection on prediction variables only or random sampling. We do so by computer simulation. Initially, simulated data were based on recent and historic data from The Netherlands. Prediction variables are fat and muscle depth measurements. The additional variable involved in sampling, but not included in the regression, was carcass weight. We also show that due to this faulty sampling scheme there is a serious risk that a new measurement instrument may not be authorized because performance criteria in the EC-regulations are not met.
Plasma leptin concentration in pre- and post-weaning lambs
Authors: Tokuda T. , Delavaud C. , Chilliard Y. 
Published: May 2019

AbstractLeptin has an important rôle in the control of appetite and energy expenditure. Several studies have reported the effects of leptin in ruminants. However, little is known about changes in circulating leptin concentrations in neonates of ruminant species, or the effects of weaning on plasma leptin concentrations. The main objectives of this experiment were: to examine plasma leptin concentrations in lambs, in the period from just after birth through to weaning; to examine the effect of weaning on plasma leptin concentrations, and to compare leptin concentrations measured using a ‘multi-species’ leptin radio-immunoassay (RIA) kit and a specific ovine RIA in lambs during the 6-month period after weaning. In a previous paper, we reported leptin concentrations using a commercial RIA during the post-weaning period. However, we were not able to measure plasma leptin concentrations from just after birth to weaning as they were apparently below the level of sensitivity of the assay. In the present study, five crossbred lambs were removed from their dams within 2 days after birth, and bottle-fed on milk replacer at a level sufficient to meet a 1•2 times maintenance metabolizable energy intake. Lambs were weaned 45 days after birth, and housed individually in pens. The lambs were offered timothy hay, rolled barley and soya-bean meal to meet a 200 g daily gain during the post-weaning period. During the pre-weaning period, blood samples were collected within 5 h of birth and thereafter at 09:00 h; every day from 2 to 6 days of age; at 2-day intervals from 6 to 14 days of age; and at 3-day intervals from 14 to 45 days of age. During the post-weaning period, blood samples were collected before and 3 and 6 h after the morning meal at the ages of 0•5, 1, 2, 3, 4, 5 and 6 months. Plasma leptin concentrations slightly increased (P < 0•05) just after birth and then remained constant until 45 days old (P > 0•05). Additionally, plasma leptin concentration was not significantly changed following weaning. During the post-weaning period, plasma leptin concentrations were compared using two RIA systems. The correlation between plasma leptin concentrations measured by the ‘multi-species’ leptin RIA kit and specific ovine RIA was poor (r = 0•41). These findings are consistent with other reports and suggest that the ‘multi-species’ leptin RIA kit is not suitable for estimating leptin plasma concentrations in ruminants.
Daily changes in antro-duodenal myoelectric activity in weaned pigs
Authors: Yao G. , Woliński J. , Korczyński W. , Zabielski R. 
Published: May 2019

AbstractThe stomach and small intestine manifest a myoelectric activity pattern called the migrating myoelectric complex (MMC), which is controlled by both environmental and intrinsic factors. The daily MMC pattern has been little investigated, therefore the purpose of the present study was to study it, in weaned pigs given food twice a day. A wireless telemetric recording system was used for 24-h electromyography of the antrum and duodenum. The activity of the antrum showed little change if any, whereas the myoelectric activity of the duodenum significantly changed with respect to the time of day and feeding in conscious pigs. Namely, there were more frequent and regular MMC cycles occurring in the duodenum at night as compared with that during daytime. This change was due to the shortening of phase II of the MMC cycles that were registered at night. Phase I of the MMC showed transient variability in relation to feeding with no impact on the day/night differences. Phase III of the duodenal MMC cycle as well as the ‘feeding pattern’ did not change along with the time of day and feeding regime. In conclusion, daily variation in the duodenum may provide different conditions for digestive processes in the day and night.
Effect of lucerne-based diets on performance of reproductive rabbit does at two temperatures
Authors: Fernández-Carmona J. , Alqedra I. , Cervera C. , Moya J. , Pascual J.J. 
Published: May 2019

AbstractNew Zealand × Californian rabbit does were offered ad libitum three diets: diet A, with 960 g lucerne per kg dry matter (DM), having 8•7 MJ digestible energy (DE) and 108 g digestible protein (DP) per kg DM; diet AF with 920 g lucerne and 50 g animal fat per kg DM, having 9•6 MJ DE and 105 g DP per kg DM; and diet C, as a control diet having 12•0 MJ DE and 122 g DP per kg DM. Productive parameters were measured for the first five parities, and food intake and milk yield during the first two parities.In experiment 1, 79 does (342 parities) were housed in a cooled building, litters were standardized to eight kits and weaned at 28 days of age. DM intake during lactation was lower (P < 0•001) but DE intake, milk yield and litter growth were higher for group C. Values for does on diet AF generally were between those of groups A and C. Average results for groups A, AF and C were respectively: 59, 65 and 51 days for the parturition interval; 160, 170 and 193 g for daily milk output in the first two lactations; 3•7, 4•0 and 4•5 kg for litter weight at weaning.In experiment 2, 64 does (294 parities) were housed in a climatic chamber at a constant temperature of 30oC, litters were standardized to six kits and weaned at 35 days of age. DM intake during lactation was lower (P < 0•001) but milk yield and litter growth were higher (P < 0•001) for C does. Average results for groups A, AF and C were respectively: 70, 70 and 56 days for parturition interval; 106, 128 and 128 g for daily milk output in the first two lactations; 3•7, 4•4 and 4•4 kg for litter weight at weaning. Lucerne-based diets allowed a reasonable performance of reproductive rabbit does in the long term, even under hot conditions.
Effect of gender, terminal sire line and age at slaughter on performance, carcass characteristics and meat quality of heavy pigs
Authors: Latorre M. A. , Medel P. , Fuentetaja A. , Lázaro R. , Mateos G. G. 
Published: May 2019

AbstractTwo hundred and forty pigs of 56 ± 3 days of age were used to investigate the effects of sex (barrows; gilts), boar sire (DD, Danish Duroc; ND × LW, Dutch Duroc × Large White ; P × LW, Pietrain × Large White) and slaughter age (160; 175 days) on performance and carcass and meat quality. Treatments were arranged factorially (2 × 3 × 2) and there were four replicates (five pigs per replicate) per treatment. The female line was Landrace × Large White in all cases. Barrows had greater daily food intake (P <0·001) and average daily gain (P <0·01) and had poorer food conversion ratio (P <0·001) than gilts. Carcasses from castrates were fatter and had a lower yield of trimmed lean cuts than carcasses from females (P <0·001). Longissimus muscle from barrows had more intramuscular fat and higher a* value than muscle from gilts (P <0·05). Pigs from DD sire line grew faster (P <0·05) and had a better food conversion ratio (P <0·001) than pigs from the other two lines. Dressing proportion and backfat thickness were greatest for P × LW sired pigs (P <0·01) and proportion of trimmed lean cuts was greater for DD and P × LW than for ND × LW sired pigs (P <0·01). Longissimus muscle from DD sired pigs had less protein (P <0·01) and more intramuscular fat (P <0·001) than muscle from the remaining lines. Longissimus muscle from P × LW line had more intense colour than muscle from DD and ND × LW lines (P <0·01). Pigs slaughtered at 175 days had poorer food conversion ratio (P <0·01) and less trimmed primal cut proportion (P <0·001) than pigs slaughtered at 160 days. Also, increasing the age at slaughter increased intramuscular fat content (P <0·01), a* value (P <0·001) and colour intensity of the muscle (P <0·01). Danish Duroc boars are a good alternative to ND × LW or P × LW boars for production of heavy pigs whether the crossbreds are sacrificed at 160 or 175 days. Also, an increase in age at slaughter impairs growth efficiency and yield of lean cuts but improves some aspects of meat quality, which might be of interest in the production of heavy pigs destined for the dry-cured product industry.
The effect of increasing the salt intake of pregnant dairy cows on the salt appetite and growth of their calves
Authors: Mohamed M. O. , Phillips C. J. C. 
Published: May 2019

AbstractAn increased sodium appetite has been demonstrated in cattle following supplementation with sodium in the neonatal period, but it is unclear whether the sodium appetite of calves can be influenced in utero by the dam’s sodium intake during pregnancy. Twenty-two non-lactating, pregnant dairy cows received either a diet of silage and concentrates or the same diet with 70 g NaCl per day added to it for the last 2 months of pregnancy. The sodium supplement increased the birth weight of their calves but after 6 weeks there was no difference between treatments in calf weight. In addition to milk, calves in both treatments were offered a choice of concentrates with normal or high sodium concentrations (5·8 and 10·8 g/kg dry matter, respectively). Calves from the cows that had received supplementary sodium during pregnancy ate more of the high sodium concentrate than calves from cows without the sodium supplement, demonstrating that sodium appetite could be entrained by the sodium intake of the dam during late pregnancy.
Factors influencing length of productive life and replacement rates in the Bruna dels Pirineus beef breed
Authors: Tarrés J. , Puig P. , Ducrocq V. , Piedrafita J. 
Published: May 2019

AbstractAn analysis of the length of productive life in the Bruna dels Pirineus beef breed was performed with a non-parametric approach giving an average value of 9 years of productive life, and a corresponding replacement rate of 11%. Using a proportional hazards model stratified by herd, the influence of calf birth weight and weight gain until weaning, calving difficulty, calving interval and age at first calving on length of productive life were studied. Two models were explored: the first one included time-dependent variables taking the current value of the covariate at each calving date, while the second one also comprised time-dependent interactions between the value of the covariate of the current calving and its mean value during the last (up to) three previous calvings. Results from the first model showed that the risk of culling increases with very high ages at first calving, increasing calving difficulties, very large calf birth weights, very small weight gains until weaning and very long calving intervals. Furthermore, results from the second model showed that these increases also depend upon a sequence of values for the same covariate in previous calvings. Finally, these higher risks of culling implied lower survival functions that increased replacement rates but only slightly decreased average performances.
Growth performance and carcass traits of Large White, Mukota and Large White ✕ Mukota F1crosses given graded levels of maize cob meal
Authors: Kanengoni A. T. , Dzama K. , Chimonyo M. , Kusina J. , Maswaure S. M. 
Published: May 2019

AbstractA study was conducted to compare the performance of Mukota, Large White (LW) and LW ✕ Mukota F1pigs given increasing levels of maize cob meal. Sixteen female weaners of each genotype were given, ad libitum, diets containing 0, 100, 200 and 300 g maize cob meal per kg of diet for 14 weeks. The diets were designed to contain similar levels of protein (ca. 160 g crude protein per kg) and energy (ca. 9 MJ metabolizable energy per kg). Average daily food intake per unit metabolic body weight (ADFI per kg M0·75), average daily gain (ADG) and food conversion ratio (FCR) were determined. The pigs were slaughtered and cold dressed mass (CDM) and backfat thickness were determined for each pig. The ADFI per kg M0·75was similar among the four diets for the three genotypes. The rate of decline in ADG was higher (P < 0·05) in the LW than in the other two genotypes. The FCR in the Mukota was poorer (P < 0·05) than that in the LW and the F1crosses. The Mukota had the highest (P < 0·05) backfat thickness (K5 and K7·5) values of the three genotypes across the four diets, followed by the F1crosses. The CDM values for the LW and the F1crosses were similar and were higher (P < 0·05) than those for the Mukota. The findings indicate that F1crosses and the Mukota were better able to utilize diets containing high levels of maize cob meal than LW pigs.
Effect of type and level of dietary fibre and starch on ileal and faecal microbial activity and short-chain fatty acid concentrations in growing pigs
Authors: Wang J. F. , Zhu Y. H. , Li D. F. , Wang M. , Jensen B. B. 
Published: May 2019

AbstractA repeated 4 ✕ 4 Latin square design was conducted with eight ileal cannulated castrated pigs to investigate the effect of source of dietary fibre and starch on ileal and faecal microflora and short-chain fatty acid concentrations. Four experimental diets based on cooked rice were supplied with one of two fibre-rich sources (sugar-beet pulp, S; wheat bran, W) and another two diets were prepared with (P) or without (C) potato starch. The experimental periods were 14 days, consisting of 7 days of adaptation to each diet, followed by 4 days of collection of ileal digesta and 3 days of collection of faeces. Ileal digesta were collected daily in a randomized order 0 (just before feeding the morning meal), 2, 4, 6 and 8 h after feeding the morning meal. Fresh faecal samples were also collected. Ileal pH was lower in pigs given diet P, 2 and 4 h after feeding, respectively. For all four diets ileal pH reached a minimum 4 h after feeding. Faecal pH was higher for diets P and W compared with diets C and S. The highest density of ileal coliform bacteria was found 4 h after feeding for all diets. Compared with other diets, the inclusion of potato starch resulted in an increased density of ileal enterococci at 0 h and an increased density of ileal lactic acid bacteria and lactobacilli, 2 and 6 h after feeding, respectively. The density of ileal enterococci reached a maximum 4 h after feeding for all diets. With the exception of 8 h after feeding, when a higher density of total anaerobes was observed for diet P, no significant differences were seen in the populations of yeasts and total anaerobes between the experimental diets. The concentration of formate in the ileum was high, while low concentrations of acetate, propionate and butyrate were observed for all diets. A lowered level of acetate was found for diet S on all sampling occasions. On a dry-matter basis, the counts of various faecal bacteria were increased by the inclusion of the fibre sources, and a higher level of faecal butyrate was found with the inclusion of potato starch or the fibre sources as compared with diet C, whereas no significant effects on the counts of various bacteria were observed with potato starch supplementation. Overall, the present results indicate that the addition of dietary fibre to pig diets resulted in an enhanced microbial fermentation.
Reproductive traits of female rabbits as affected by heat stress and lighting regime under subtropical conditions of Egypt
Authors: Marai I. F. M. , Habeeb A. A. M , Gad A. E. 
Published: May 2019

AbstractThe present work was planned to study the effects of different lighting regimes in both mild and hot periods of the year on New Zealand White doe rabbit traits. The light regimes used were natural daylight as control, 16 h light and 8 h darkness, 12 h light and 12 h darkness, and 8 h light and 16 h darkness. The traits studied were thermoregulatory parameters (respiration rate and temperatures of ear, rectum and skin), type of mating necessary, conception rate, gestation period, fur plucking, behavioural indicators of stress, litter size, litter weight, kit body weight, kit daily gain in weight, milk yield, kit milk intake, efficiency of conversion of milk into live-weight gain and kit mortality, at weekly intervals between birth and weaning at 35 days. Estimation of temperature-humidity index indicated that the doe rabbits were exposed to very severe heat stress, during the hot period of the year. Period of the year (heat stress) affected adversely many of the doe traits studied. The effects were significant (P < 0·001, 0·01 or 0·05) on thermoregulatory parameters (respiration rate and temperatures of ear, rectum and skin), litter weight at days 21 and 28 of age, kit body weight at birth, milk yield of the doe at day 7 of suckling and milk intake per kit at 7 and 14 days of age. Exposure of doe rabbits to a long daylight regime affected adversely many of the traits studied, while the contrary occurred with short daylight. The effects were significant (P < 0·001, 0·01 or 0·05) on litter size at all ages except at birth, litter weight at 14, 21 and 28 days of age, milk yield on all days studied, efficiency of conversion of milk into live-weight gain at days 7, 21 and 28 and mortality at birth and pre-weaning. There was no significant interaction between period of the year and light regime on any of the traits examined. Therefore, only the main factors are reported.