REPRODUCTIVE PERFORMANCE OF GILTS FED RAPESEED MEAL CV. TOWER DURING GESTATION AND LACTATION

Abstract

Reproductive traits were studied on 64 gilts averaging 112 kg which were fed diets containing 0 or 10% of cv. Tower rapeseed meal (RSM) when they were diagnosed pregnant. No significant differences in litter size and weight at birth and at weaning were observed (P > 0.05) between gilts fed 0 or 10% RSM. The first postpartum estrus observed after weaning at 28 days and the ovulation rates at first estrus were similar for the two groups. The thyroid weight was not affected by the treatment. Resin sponge intake (a product of T 3 and total serum thyroxine T 4) of labeled 3-5-3′-triiodothyronine (T 3) was lower (P < 0.05) at the 110th day of pregnancy for sows fed 10% RSM. However, at weaning and 3 days after the first postpartum estrus, T 3 test results, T 4 concentrations and free thyroxine index were comparable for sows fed 0 and 10% RSM. Between the three stages studied, only T 3 test results and T 4 concentration varied significantly independently of the feeding regimes.