Digestion of fat does not differ in growing pigs fed diets containing fish oil, rapeseed oil or coconut oil

Abstract

We studied the digestion of fat and fatty acids in diets containing oils with different fatty acid composition. Four barrows (initial weight 35 kg) were fitted with a simple T-cannula at the terminal ileum. Three wheat starch and fish meal-based diets were formulated to contain either 150 g fish oil, rapeseed oil or coconut oil/kg. A basal diet, which did not contain oil, was also prepared. The diets were fed according to a 4 x 4 Latin square design. Each experimental period comprised 5 d adaptation to the diets, 3 d fecal collection and 2 d digesta collection. The apparent ileal and fecal digestibilities of fat were relatively high (88 - 93%). The ileal digestibilities of total, saturated and monounsaturated fatty acids did not differ among the diets. However, the digestibilities of polyunsaturated fatty acids (PUFA) in the fish and rapeseed oil diets were higher (P < 0.05) than in the coconut oil diet. The ileal digestibilities of 18:1, 18:2 and 18:3 in the rapeseed oil diet ranged from 94 to 97%. The ileal digestion of the unsaturated long-chain fatty acids 20:5(n-3) and 22:6(n-3) in the fish oil diet was nearly complete (97 - 98%). Apparent fecal digestibilities of saturated fatty acids (76 - 89%) were lower than apparent ileal digestibilities (89 - 94%). The digestibilities of fat and fatty acids were relatively high when pigs were fed diets containing fish oil, rapeseed oil or coconut oil. There were few differences in the digestibilities of saturated, monounsaturated and PUFA in the fish oil, rapeseed oil or coconut oil diets.