Genetic analysis of individual piglet traits together with juvenile IGF-1 and performance traits

Heavier piglets are more likely to survive until weaning (see review by Le Dividich, 1999). Piglets with a larger birthweight have a higher pre-weaning growth rate (Bilkei and Biro, 1999) and better lifetime performance (Rydhmer et al., 1989). Overall, these phenotypic relationships indicate the importance of considering the role of piglet birth weights in breeding programs. In addition, further piglet weight traits may be recorded during lactation or at weaning. These traits provide further information about the combined potential of the piglet to grow and the mother to nurse a litter. As such piglet traits recorded after birth are of importance. However, cross-fostering is often practiced in nucleus herds and may limit the use of piglet traits recorded after birth.