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The objective of this study was to determine the effect of individual piglet birth weight on mortality and pig quality in a U.S. commercial production system. Pigs used in this study were farrowed from Large White x Landrace sows ...
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The objective of this study was to determine the effect of individual piglet birth weight on mortality and pig quality in a U.S. commercial production system. Pigs used in this study were farrowed from Large White x Landrace sows (n = 463) bred to Duroc boars during a 4 week period at a commercial sow farm. Within 24 h of birth, all pigs (born alive = 5727 and stillborns = 513) were weighed and individually indentified. A portion of pigs (16.7%) were cross-fostered to reduce litter size variation during lactation. Individual mortality was recorded daily during the suckling phase. Pigs were weighed 2 days prior to weaning (18.7 +/- 2.1 days of age), finisher placement (74.8 +/- 1.9 days of age), and 16 weeks into finishing (172.8 +/- 1.8 days of age). During BW collections, an inventory of all live pigs was conducted, and pigs were given a quality score based on visual evaluation of BW and health (3 = healthy pig; 2 = slightly small and/or slightly unthrifty; 1 small and/or unthrifty). Survival was analyzed for 4 distinct time periods (prenatal, pre-weaning, nursery phase, and finishing phase). Data were analyzed using a logit (survival) or cumulative logit (quality score) function. Birth weight linear effects on prenatal, pre-weaning, and nursery survival as observed mortality probability increased as birth weight decreased. However birth weight did not impact the likelihood of survival during finishing. As birth weight decreased, the likelihood of pigs being poorer quality, quality score (1 or 2), at weaning, finisher placement, and 16 weeks into finishing, increased. As birth weight increased the likelihood of a pig being full value at the end of the finishing phase increased. Reduced individual piglet birth weight, was associated with reduced pig quality and likelihood of prenatal, pre-weaning, and nursery survival. Because of the negative impact of birth weight on pre-weaning and nursery survival and pig quality in finishing, as birth weight decreased pigs were less likely to be full value at harvest
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Genome scans in the pig have identified a region on chromosome 2 (SSC2) associated with tenderness. Calpastatin is a likely positional candidate gene in this region because of its inhibitory role in the calpain system that is invo...
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Genome scans in the pig have identified a region on chromosome 2 (SSC2) associated with tenderness. Calpastatin is a likely positional candidate gene in this region because of its inhibitory role in the calpain system that is involved in postmortem tenderization. Novel single nucleotide polymorphisms (SNP) in calpastatin were identified and used to genotype a population (n = 1042) of Duroc-Landrace-Yorkshire swine for association with longissimus lumborum slice shear force (SSF) measured at days 7 and 14 postmortem. Three genetic markers residing in the calpastatin gene were significantly associated with SSF (P < 0.0005). Haplotypes constructed from markers in the calpastatin gene were significantly associated with SSF (F-ratio = 3.93; P-value = 0.002). The levels of normalized mRNA expression of calpastatin in the longissimus lumborum of 162 animals also were evaluated by real-time RT-PCR and were associated with the genotype of the most significant marker for SSF (P < 0.02). This evidence suggests that the causative variation alters expression of calpastatin, thus affecting tenderness. In summary, these data provide evidence of several significant, publicly available SNP markers associated with SSF that may be useful to the swine industry for marker assisted selection of animals that have more tender meat.
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摘要 :
Genome scans in the pig have identified a region on chromosome 2 (SSC2) associated with tenderness. Calpastatin is a likely positional candidate gene in this region because of its inhibitory role in the calpain system that is invo...
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Genome scans in the pig have identified a region on chromosome 2 (SSC2) associated with tenderness. Calpastatin is a likely positional candidate gene in this region because of its inhibitory role in the calpain system that is involved in postmortem tenderization. Novel single nucleotide polymorphisms (SNP) in calpastatin were identified and used to genotype a population (n = 1042) of Duroc-Landrace-Yorkshire swine for association with longissimus lumborum slice shear force (SSF) measured at days 7 and 14 postmortem. Three genetic markers residing in the calpastatin gene were significantly associated with SSF (P < 0.0005). Haplotypes constructed from markers in the calpastatin gene were significantly associated with SSF (F-ratio = 3.93; P-value = 0.002). The levels of normalized mRNA expression of calpastatin in the longissimus lumborum of 162 animals also were evaluated by real-time RT-PCR and were associated with the genotype of the most significant marker for SSF (P < 0.02). This evidence suggests that the causative variation alters expression of calpastatin, thus affecting tenderness. In summary, these data provide evidence of several significant, publicly available SNP markers associated with SSF that may be useful to the swine industry for marker assisted selection of animals that have more tender meat.
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Genetic parameters for scale activity score (AS) were estimated from generations 5, 6, and 7 of a randomly selected, composite population composed of Duroc, Large White, and 2 sources of Landrace (n = 2,186). At approximately 156 ...
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Genetic parameters for scale activity score (AS) were estimated from generations 5, 6, and 7 of a randomly selected, composite population composed of Duroc, Large White, and 2 sources of Landrace (n = 2,186). At approximately 156 d of age, pigs were weighed (BW) and ultrasound backfat measurements (BF1, BF2, and BF3) were done. While pigs were in the scale, an AS was assigned, which ranged from 1 (calm) to 5 (highly excited), where 58.1, 28.5, 8.9, 4.0, and 0.5% were scored as 1, 2, 3, 4, and 5, respectively. Statistical model effects were year-week of measurement, sex, covariates of age for AS and BW or BW for BF1, BF2, and BF3, and an animal direct genetic effect. A 5-trait linear mixed model was used. Estimated heritabilities were 0.23, 0.54, 0.56, 0.52, and 0.48 for AS, BW, BF1, BF2, and BF3, respectively. Estimated genetic correlations between AS and BW, AS and BF1, AS and BF2, and AS and BF3 were 0.38, 0.11, 0.12, and 0.16 respectively. Results indicated AS had a heritable genetic component and was genetically correlated with performance traits. Estimated genetic correlations between AS and backfat measurements adjusted to a common BW were negative, as was the genetic correlation of AS with BW. Therefore, selection for more docile animals would be expected to result in fatter, faster growing pigs.
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Commercial swine production has become an increasingly globalised industry, with global meat trade demanding that all regions compete on cost and differentiation of pork products. The utilisation of continually improving genetic p...
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Commercial swine production has become an increasingly globalised industry, with global meat trade demanding that all regions compete on cost and differentiation of pork products. The utilisation of continually improving genetic populations can be one input that helps maintain, or increases, the competitiveness of an individual producer or regional industry. So as to deliver these improving genetic populations, genetic providers of today must focus on developing and implementing best science that delivers improvement on traits affecting commercial profitability. Providers must also efficiently multiply and disseminate the improved merit to the commercial hog production level. The swine-genetics industry has made considerable progress in driving a faster genetic gain over the past 30 years by systematically combining ever-changing computing power, accurate data capture and emerging genomics information. The combination of these technologies today has resulted in hundreds of thousands of animals being genotyped for tens of thousands of markers, and this information is being combined with extensive phenotypic data to deliver rates of genetic gain nearly double what we were able to achieve 20 years ago. As importantly, this scientific advancement can then be combined with the ability to continue to understand and evaluate emerging traits related to animal robustness, well-being and consumer demand, resulting in the most comprehensive definition of selection targets in the history of modern animal improvement. Finally, managing the dissemination of these genes through boar stud and multiplication systems helps ensure that the commercial level minimises lag and utilises the highest-merit genetics available.
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