Abstract
This review discusses the biological significance of colostrum intake for neonatal development in pigs, and discusses the variation in colostrum intake in relation to piglet and sow factors. Lack of or insufficient colostrum intake reduces the odds of survival and compromises immunity, development of the gastrointestinal tract and other organs in neonate piglets. Colostrum intake is linearly related to pre-weaning gain. It is estimated that 10%-30% of piglets consume insufficient colostrum (< 250 g). Colostrum intake is less in piglets from larger litters, in piglets born later in the birth order, in piglets with low birth weight, and in piglets mildly or severely affected by asphyxia. Colostrum yield by sows peaks between parity two and five and then declines again, and is probably related to mammary gland tissue mass and endocrine factors involved in colostrogenesis. Before farrowing, the decline in progesterone facilitates and the increase in prolactin initiates secretion of colostrum, and the changes in both these hormones are related to colostrum yield. Feeding level and fibre may accelerate the decline in progesterone and in that way increase colostrum yield. Earlier during the third trimester of pregnancy, proper management of energy intake and sow body condition is important to optimise mammary gland development. Specific amino acids may be involved in mammary gland development, potentially through IGF-1.