Digestion and absorption of lipids by sheep fed chopped and ground dried grass.

Three wether sheep equipped with re-entrant cannulae at the proximal duodenum and terminal ileum were given dried cocksfoot in the chopped or ground form and the samples of duodenal and ilea! digesta and faeces obtained for both diets were analysed for individual long-chain fatty acids. The total quantities of fatty acids entering the proximal duodenum (15.2 and 15.4 g/24 h on chopped and ground feed, respectively) were markedly higher than the amounts consumed (8.7 and 7.8 g/24 h, respectively), whilst losses within the small intestine were 13.9 and 14.2 g/24 h, respectively. None of these effects was found to be signifi­ cantly influenced by the processing of the diet (P > 0.05). The quantity of C18 unsaturated fatty acids in the two feeds comprised 78 % of the total fatty acids but the level of these acids was considerably reduced (19%) in duodenal digesta and was not significantly influenced by diet (P > 0.05), whilst the levels of stearic acid (C18: 0) entering the small intestine were markedly increased on both diets.