Effect of the polymorphism of genes related to lactogenesis in pigs on colostrum and milk composition and on rearing performance of piglets

The aim of the study was a search for new polymorphisms in the genes related to lactogenesis, including lactose synthesis in colostrum and milk, and determine their relationship with the content of colostrum and milk components and body weight of the piglets. Colostrum and milk were sampled during the second lactation on d 1, 7, 14 and 21 from 112 sows of Polish Large White (PLW) and Polish Landrace (PL). The piglets’ rearing performance was determined based on the number and body weight at 1, 7, 14 and 21 d of age. In the study six polymorphisms located in different genes were analysed. Among the six polymorphisms under analysis, those identified in the B4GALT1 genes had the most significant effect on colostrum and milk composition and the piglets’ body weight changes. Sows of the B4GALT1^GG genotype, when compared to those of B4GALT1^AA, produced colostrum and milk with a significantly lower lactose content and reared piglets with a substantially higher body weight (by 0.30 kg) at 21 d of age.