Influence of genotype on metabolic variables, colostrum and milk composition of primiparous sows

Composition of colostrum and milk in first-parity sows from four genetic lines, namely, synthetic Belgian Landrace/Pietrain (B), Duroc (D), Landrace (L) and Yorkshire (Y) were determined. Circulating concentrations of leptin, IGF-I, glucose and FFA were also measured in sows. Differences in colostrum and milk composition were observed between genotypes, but did not generally seem related to variables in blood. Colostrum and day-2 milk from D sows contained more protein (P < 0.05) and less lactose (P < 0.1) than that from sows of other genotypes. Results suggest that selection strategies to improve the composition of milk and colostrum of sows. from European breeds could be a useful tool to increase their lactation potential.