THE EFFECTS OF FAT SUPPLEMENTATION ON ILEAL VERSUS FECAL FAT DIGESTIBILITIES, PERFORMANCE AND BODY COMPOSITION OF WEANED PIGS

Abstract

Two experiments were conducted with 28-d-old pigs to study the effects of 0 or 8% added fat to the diet when constant nutrient to energy ratios were maintained. In exp. 1, 24 pigs were assigned to one of six treatments. Pigs were fed either ad libitum or restricted. Digestibility values were determined using fecal and terminal ileum collection methods. Only apparent ether extract digestibility increased (P < 0.001) with the addition of fat to the diet. Ether extract digestibility coefficients determined by the ileal collection method were significantly larger (P < 0.001) than those determined by fecal collection. In contrast apparent energy, dry matter and crude protein digestibilities based on ileal collection were significantly lower than the equivalent digestibilities based on fecal collection. The second experiment compared the performance and carcass composition of pigs fed the same diets as in exp. 1. Pigs 7 d after weaning contained less fat (P < 0.01), more water (P < 0.001) and more protein (P < 0.01) than pigs at weaning. Carcass composition of the pigs 7 d after weaning and at 20 kg liveweight were similar (P > 0.05). Feed conversion efficiency was improved (P < 0.001) by the addition of fat to the diet. Key words: Weaned pigs, fat, digestibility, performance, body composition