Influence of non genetic factors on Large White sows productivity

Abstract

The effects of year and season of birth, litter order and the interaction between year and season of birth on sow productivity traits were analysed on 801 litters of 255 Large White sows. The traits studied were litter size and litter weights at birth, 21 days of age and weaning, and the number of stillborn. Year of birth didn't affect the traits. Season of birth affected almost all the characters analysed, with lower productions in the warm and high humidity seasons. The interaction year/season showed influence only on the traits at farrowing. Litter order affected all the traits, with the best productions between the second and the fourth litters, and decreased latter. These non genetic effects showed that they must be considered in such analysis, because their effects can go up to 25% on total sow performance.