不同品系杜洛克及其杂种公猪的杂交效果研究

对美系和台系两个杜洛克纯系及其系间杂交的公猪进行了包括繁殖、生长、胴体和肉质性能的综合杂交效果研究.结果表明,在繁殖力性状上,美系杜洛克公猪所配母猪的产仔数略高于台系杜洛克(11.88头:11.54头),但两者无显著性差异.系间杂交公猪所配母猪的产仔数也与纯系所配母猪的产仔数相近.但在20日龄窝仔数和窝重性状上,杂种公猪优于纯种公猪.美系和台系公猪所产后代的平均日增重几乎完全相同.美系和台系血统各为50%杂交公猪所产后代的生长速度最快,其平均日增重分别比美系组和台系组高11.04%和10.37%.台系杜洛克所配后代的胴体瘦肉率最高. 杂种公猪后代的肌内脂肪含量明显高于两个纯系公猪后代,美系公猪后代的肌内脂肪含量显著高于台系公猪后代(1.57%:1.17%).

Effects on crossing performance of two Duroc strains and their hybrid boars

An experiment was carried out to make comprehensive comparisons in crossing performance between pure US and Taiwan Duroc strains and their hybrids boars. The results indicated that sows mated with US Duroc boars produced slightly higher litter size (11.88) than that mated with Taiwan Duroc (11.54), but there was not a significant effect. Crossbred Duroc was not better than pure ones for litter size at birth. However, for litter size and litter weight at the age of 20 d, crossbred Duroc mated groups appeared superior to pure ones. The average daily gains of pigs sired by two pure Duroc were almost the same, but pigs sired by Duroc with 50% US and 50% Taiwan grew the fastest and their average daily gains were 11.04% and 10.37% higher than those sired by pure US and Taiwan Duroc strains.The pigs sired by Taiwan Duroc had the highest lean percentage of carcass. Intramusclar fat contents were distinctively higher sired by crossbred Duroc than by pure animals. The pigs sired by pure US Duroc produced a significantly higher intramusclar fat content compared with those sired by pure Taiwan Duroc (1.57%∶1.17%).