Department of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, PO Box 8146 Dep., 0033 Oslo, Norway.
J Anim Sci. 2012 Jan;90(1):152-8. doi: 10.2527/jas.2011-3851. Epub 2011 Aug 19.
Genetics of different pig lines affects litter size, birth weight, and neonatal losses. Low birth weight has long been associated with neonatal losses, but piglet body mass index is reported to show stronger correlation with stillbirth. The aim of this study was to investigate differences in litter size, number of stillborn piglets, piglet BW gain, and body mass index between 2 different Duroc crossbred lines. Landrace × Yorkshire sows in 2 farms (n = 89) were divided into 2 groups on each farm. One group of sows on each farm was inseminated with semen from Landrace × Duroc boars (boar group LD, n = 48), and the other was inseminated with semen from purebred Duroc boars (boar group DD, n = 41). Piglets were monitored from birth to weaning at the age of 5 wk. Litter size in boar group LD was larger than in boar group DD (P = 0.03). Number of stillborn piglets in boar group LD tended to be greater than in boar group DD (P = 0.07). Piglets in boar group DD had a greater BW at birth (P = 0.02) and at 3 wk (P = 0.01) than those in boar group LD. Body mass index from birth to weaning was greater in piglets in boar group DD vs. LD (P < 0.01), and both BW and body mass index of liveborn piglets at birth for both groups combined showed a positive correlation with survival at weaning (P < 0.01). In conclusion, breeding for larger litter size in boar group DD may be one approach to increase the number of vigorous piglets in production, but the inverse relationship between litter size and birth weight was more pronounced for this group than for boar group LD (P = 0.03). Further studies of the impact of litter size on BW gain are necessary before a final conclusion can be reached.
不同猪种的遗传因素会影响窝产仔数、初生重和新生仔猪死亡。长期以来，低初生重与新生仔猪死亡有关，但仔猪的体质量指数与死产的相关性更强。本研究旨在研究 2 个不同杜洛克杂交系之间的窝产仔数、死产仔猪数、仔猪 BW 增重和体质量指数的差异。2 个农场（n = 89）的长白猪×约克夏母猪分为 2 组。每组母猪分别用长白猪×杜洛克公猪（公猪组 LD，n = 48）和纯种杜洛克公猪（公猪组 DD，n = 41）的精液配种。从出生到 5 周龄断奶期间对仔猪进行监测。公猪组 LD 的窝产仔数大于公猪组 DD（P = 0.03）。公猪组 LD 的死产仔猪数有多于公猪组 DD 的趋势（P = 0.07）。公猪组 DD 的仔猪初生重（P = 0.02）和 3 周龄体重（P = 0.01）均大于公猪组 LD。从出生到断奶，公猪组 DD 的仔猪体质量指数大于公猪组 LD（P < 0.01），两组活产仔猪的初生重和体质量指数均与断奶成活率呈正相关（P < 0.01）。综上所述，在公猪组 DD 中培育更大的窝产仔数可能是增加生产中活力仔猪数量的一种方法，但与公猪组 LD 相比，该组的窝产仔数与初生重的负相关更为显著（P = 0.03）。在得出最终结论之前，还需要进一步研究窝产仔数对 BW 增重的影响。
