不同类型母猪死胎分析

Analysis of Stillbirth in Different Types of Sows

对二花脸猪、大白猪及其杂交一代 3个类型共计 16 86窝死胎性状进行了统计分析。二花脸猪、大白猪及其杂交一代每窝死胎数 (numberstillborn ,NSB)平均值分别为 0 .87、0 .32和 0 .72 ,产活率 (percentagebornalive ,PBA)分别为 95 .1%、97.1%和 95 .7% ,表明窝产仔数较高的二花脸猪其每窝死胎数也较高。方差分析结果表明 ,交配类型、胎次、分娩年份×分娩季节互作、总产仔数对NSB、PBA均有极显著 (P <0 .0 0 1)影响 ;分娩季节对NSB有极显著(P <0 .0 1)影响 ,对PBA有显著 (P <0 .0 5 )影响 ;分娩年份对NSB没有显著 (P >0 .0 5 )影响 ,对PBA有极显著 (P <0 .0 1)影响。从第 1胎到第 10胎 ,NSB最小二乘平均值有随胎次增长而逐渐增加的趋势 ,PBA最小二乘平均值有随胎次增长而逐渐下降的趋势。冬季分娩的母猪具有最高的NSB ,秋季最低 ;秋季分娩的母猪具有最高的PBA ,冬季最低。NSB最小二乘平均值随总产仔数增加而明显增加 ,表明两者之间存在正表型相关 ;PBA最小二乘平均值随总产仔数增加而明显下降 ,表明两者之间存在负表型相关。父系半同胞法估计结果表明 ,NSB和PBA的遗传力分别为0 .111和 0 .12 3,两者之间的遗传相关、表型相关和环境相关分别为 - 0 .985、- 0 .94 7和 - 0 .94 2。

Statistical analysis was conducted on stillbirth traits of three mating types with 1686 litters including Erhualian pig, Large White and F 1. The number of still born (NSB) per litter in Erhualian pig, Large White and F 1 averaged 0.87, 0.32, 0.72, and the percentage born alive (PBA) averaged 95.1%, 97.1%, 95.7 %, respectively. The results of variance analysis indicated that mating type, parity, farrowing year × farrowing season interaction and total number born had highly significant effects on NSB and PBA in sows (P< 0.001 ). Farrowing season had highly significant effects on NSB (P<0.01), and significant effects on PBA (P<0.05). Farrowing year had no significant effects on NSB (P>0.05), but highly significant effects on PBA (P< 0.01 ). From parity 1 to parity 10, the least squares means for NSB progressively increased with increasing parity, the least squares means for PBA progressively decreased with increasing parity. The sows farrowed in winter had the highest NSB and the lowest PBA; the sows farrowed in autumn had the lowest NSB and the highest PBA. The least squares means for NSB markedly increased with an increase in the total number born, indicating a positive phenotypic correlation existed between them. The least squares means for PBA markedly decreased with an increase in the total number born, indicating a negative phenotypic correlation existed between them. The paternal half sib estimation results indicated that the heritabilities for NSB and PBA were 0.111 and 0.123. The genetic correlation, phenotypic correlation and environmental correlation between them were -0.985 , -0.947 and -0.942, respectively.