| In this paper, the reproductive performance and its genetic effects were analyzed with the breeding data from Xiangcun Black Pig breeding farms and reproduction farms. This provided theoretical and technical basis for furtherly understanding and studying reproductive performance of Xiangcun Black Pig, and also accumulated experience for Chinese pig breed selection and genetic breeding. The results showed that:Xiangcun Black Pig had relatively high farrowing performance, for primiparous and multiparous sows, the total number born were 11.11 and 13.18, the number of born alive were 10.32 and 12.86 respectively.The litter size at 21d were 9.86 and 12.14, the piglet breeding rates were 95.90% and 95.68%, the litter weight at 21d was 42.03kg and 56.06kg respectively.Xiangcun Black Pig had fast growth rate, for primiparous and multiparous sows, piglet weight at 70d were 18.25kg and 19.76kg, litter weight at 21d was 172.29kg and 232.91kg respectively.With the model Y=Xb+Zu+Wm+Slpe+S2tm+e, the estimated heritability for TNB, NBA, LWB and LW21 was in the range of 0.07～0.18 in Xiangcun Black Pig, the maternal effect and the litter effect were in the range of 0.07～0.11 and 0.14～0.33 respectively.Conventional breeding techniques were used in breeding of Xiangcun Black Pig, the high reproductive characteristics were gained because of female parent selection for litter size 14 above, selection to offspring of high reproductive sows and the technology of overlapping generations. As a result, the selection to offspring of high reproductive sows and the technology of overlapping generations, is one of the important means of improving reproductive performance in conventional breeding.The study showed that, not including dead pigs in 12 hours after birth, the raising rates in day 21 and day 70 for piglets of primiparous and multiparous sows were increased by 6.21%,6.03%,1.29% and 1.24% respectively. To strengthen the management and reduce the death of live newborn is very important in pig production. |
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