EFFECT OF GENETIC AND NONGENETIC FACTORS ON REPRODUCTIVE PERFORMANCESOF LANDRACE, LARGE WHITE AND DESI PIGS AND THEIR CROSSES

The present study was carried out on 89 sows of 5 genetic groups consi sting of pure desi(D), Landrace (LR), Large White Yorkshire (LWY) and crosses of desi sows with LR and LWY boars maintained at Ranchi Veteri nary College and Government Pig Breeding Farms at Kanke and Hotwar. Le ast-squares analysis of variance showed significant (P<0.01) effect of genetic groups and parity of sows on all the reproductive performance s, viz. gestation period, litter size at birth and at weaning, and lit ter weight at birth and at weaning. However, the effect of season of f arrowing on reproductive performances was nonsignificant. A significan t superiority in litter size, apart from litter weight at birth and at weaning, is an additional advantage in economic traits by crossing de si sows with exotic boars than that of desi sows with desi boars. Sign ificantly lowest values were observed in first and fourth parity, resp ectively, for all the 5 reproductive traits. There was a progressive i ncrease in reproductive performances with the advancement of parity.