妊娠 110 d背膘卡尺评分及胎次对二元回交母猪繁殖性能的影响OA

Production records of 1 072 backcross binary sows from a breeding farm in Guizhou Province were ana-lyzed using one-way ANOVA and correlation regression to evaluate the effects of backfat caliper score at day 110 of gestation and parities on reproductive performance of sows.The practical utility of the caliper scoring system in sow production management was further evaluated.The results showed that:1)Parity significantly(p<0.05)influenced the reproductive performance of backcross binary sows,with optimal performance observed in parities 1-4 and marked declines after parity 7.2)In primiparous sows,the group of caliper score≤17 demonstrated the highest to-tal number of born,number of born alive,and number of healthy born.This group also had significantly greater litter birth weight and weaning weight of piglets than the>22 group.Both the(17,20)and[20,22]groups exhibited significantly higher average piglet birth weight compared with the other groups.Additionally,their litter birth weight and piglet weaning weight were also significantly greater than those observed in the>22 group.For multiparous sows,the group of caliper score≤17 had the highest reproductive performance,followed by the(17,20)group.3)Extremely significantly(p<0.01)negative correlations were observed between backfat caliper scores and litter birth weight,birth weight,and weaning weight of the piglets in primiparous sows,with optimal reproductive performance achieved at scores of 19-21.Whereas,the number of born alive and litter birth weight of piglets were significantly negatively correlated with the caliper score of multiparous sows,and the scores were better at 18-20 points.In con-clusion,the reproductive performance of backcross binary sows is optimal during parities 1-4,and culling is recom-mended after parity7;the backfat caliper score for primiparous sows should be maintained within19-21,while that for multiparous sows should be kept at 18-20.