DIETARY RAPESEED MEAL FOR SWINE REPRODUCTION

Twenty-four sows (six littermate groups of four sows each) from 29 to 106 kg liveweight were fed either 0 or 8% solvent-extracted rapeseed meal, substituted on an isonitrogenous basis for soybean meal and wheat. The two groups were then subdivided to receive either 0 or 8% rapeseed meal in their diets through two complete reproductive cycles.Average daily gain of gilts fed rapeseed meal was lower throughout the growing period but was significantly depressed only from 90 to 106 kg liveweight. Number of services to conception, gestation weight gains, gestation length and lactation weight losses were not significantly influenced by dietary treatment. In the first reproductive cycle, sows fed rapeseed meal during the growing period farrowed only 0.2 pigs less per litter than those fed the diet containing soybean meal, but weaned 2.5 pigs less which resulted in a reduced litter weaning weight.During the second reproductive cycle, treatment during growth had no significant influence on performance of the sows or litters. Sows fed rapeseed meal during gestation and lactation performed as well during both reproductive cycles as those fed the soybean meal diet. The results indicate that levels of 8% rapeseed meal should not be fed to growing gilts that are to be saved for reproduction.