DIGESTION AND METABOLISM OF DIETARY-FAT IN FARM-ANIMALS

Fat digestion and metabolism differ widely between animal species. In ruminants, dietary fats are hydrogenated in the rumen before intestina l absorption so that absorbed fatty acids (FA) are more saturated than dietary FA. In non-ruminants, intestinal FA digestibility depends on the level of saturation of dietary FA. Fat supplementation of the diet of cows decreases milk protein and has a variable effect on milk fat, depending on the source of dietary lipids. When encapsulated Lipids a re used, the linoleic acid content of milk is increased, but the organ oleptic quality of milk may be altered. Supplementary lipids are incor porated into non-ruminant body fat, whereas de novo lipogenesis is red uced. There is a close relationship between the nature of dietary FA a nd non-ruminant body FA.