Effect of bovine colostrum on the serum insulin-like growth factor-I (IGF-I), the IGF binding proteins-2 and -3 and the thyroid hormones in weaning piglets

This study examined the effect of a bovine colostrum supplementation on growth performance, feed intake and the hormonal response of piglets at weaning. Ninety-six newly-weaned piglets were assigned for four weeks to one of the two treatments: Control (diet with bovine milk whey) and Colostrum (diet with bovine colostrum whey) treatments. The supplements were incorporated in a commercial diet at 20 g/kg during the first 2 weeks after weaning and lowered to 10 g/kg for the next 2 weeks. Body weight and feed intake were measured weekly. Blood samples were taken weekly for determination of circulating IGF-I, its binding proteins and the thyroid hormones (T3 and T4). During the first week of the trial, the Colostrum-fed piglets presented improved growth performance, feed intake and feed efficiency and a higher concentration in circulating IGF-I (+ 15 %) compared to the Control piglets. In both treatments, the circulating thyroid hormones were reduced by weaning and the levels measured at weaning were recovered earlier by the Colostrum-fed piglets compared to the Control group (P < 0.05). It is concluded that hormonal response observed after the bovine colostrum supplementation is, at least in part, consequent of the positive action of bovine colostrum on the feed intake.Valorisation du colostrum bovin en production porcine, comme alternative aux antibiotique