EFFECT OF INBREEDING ON THE PERFORMANCE OF LARGE WHITE YORKSHIRE SOWS

Abstract

Data relating to 130 sows, 19 boars from 400 farrowings spread over a period from 1984 to 1992 were utilized to study genetic and non-genetic effects on variation of litter size at birth and litter size at weaning. The over• all litter- size at birth was 6.83 ± 6.13 piglets. The effects of period and season of fat-rowings and breeding group on litter size at birth were non-significant (P > 0.05). The overall least squares mean of litteisize at weaning was 4.83 ± 0.12 piglets and was significantly (P £ 0.05) reduced by inbreeding (breeding group) and over the period. The heritability estimates of litter• size at birth and litter size at weaning were 0.09 ± 0.09 and 0.81 ± 0.27 1-espectively. Litter size at birt ignificant (P £ 0.01) con•elation (0.64 ± 0.03}.