Author : Pollung H. Siagian

Summary : The reproductive performance data of 3,266 Yorkshire, 1,495 Landrace, and 1,451 Duroc sows which farrowed in December 1979 - November 1983 as well as the productive performance data of 1,882 Yorkshire, 1,100 Landrace, and 881 Duroc boars and 3,178 Yorkshire, 1,806 Landrace, and 1,131 Duroc gilts which completed their performance test in the same period were used in this study. The traits associated with sow productivity obtained from the Yorkshire, Landrace, and Duroc were: number of pigs born alive, 9.25, 9.22, and 7.78; number of pigs born dead: 0.86, 0.68, and 0.69; average litter size at birth: 10.11, 9.91, and 8.46; litter size at weaning: 7.58, 7.87, and 5.05; weaning age: 36.12, 37.44, and 37.41 days; percent stillborn pigs: 6.77, 5.30, and 6.81; weaning percentage based on total pigs born: 75.35, 80.13, and 60.50; weaning percentage based on pigs born alive: 80.71, 84.77, and 64.71; pig birth weight: 1.34, 1.49, and 1.52 kg; litter birth weight: 11.87, 13.15, and 11.37 kg; pig weaning weight: 5.98, 6.53, and 6.10 kg; litter weaning weight: 47.11, 51.67, and 34.69 kg; gestation period: 114.31, 114.73, and 114.29 days; age at first breeding: 275.28, 273.37, and 269.79 days; age at first farrowing: 407.07, 410.42, and 401.72 days; interval between weaning to conception: 25.23, 31.22, and 23.92 days; and interval between two consecutive farrowings: 172.07, 181.21, and 169.11 days, respectively. The effects of breed on most of the reproductive traits were highly significant.