Effects of Direct Additive and Direct Dominance on Litter Traits in Crossbred Sows between Danish Yorkshire and Danish Landrace Pigs in Vietnam

Abstract

Background: The objectives of this study were to estimate the effects of direct additive and dominance on litter traits and to predict the reproduction of un-tested crossbred sows between Danish Yorkshire (Y) and Danish Landrace (L) pigs in Vietnam. Methods: Litter traits data were obtained between 2014 and 2017 in Binh Thang and Khang Minh An breeding farms, with 671 litters of crossbred sows crossed from 1,308 litters of purebred Yorkshire and Landrace sows. Result: In F1 sows, heterosis was manifested in all traits with 6.7-6.4% for TNB; 5.4-6.2% for NBA; 4.4-4.8% for NW and 5.7-6.0% for AWW traits. Additionally, direct dominance was the most positive effect on litter traits in crossbred sows. In rotational crossbred sows of L (YL) and L (LY), while the value of litter traits remarkably decreased in comparison with F1 groups, it was a noticeably higher than that of the purebred sows by 1.4-3.0%. In un-tested crossbred groups of Y (YL) and Y (LY), predicted values for litter traits were equal in tested crossbred groups of L (YL) and L (LY) and lower than F1 crossbred sows.