Six pigs (initial weight 30 kg) were fitted with T-shaped cannulas in the ileum, 0.3 m from the ileocaecal junction. Each pig was given each of seven diets for a 10 d period. The diets contained wheat (var. Banks and Egret), barley, sorghum, meat meal, soya-bean meal or casein as test feedstuffs. The apparent digestibilities of biotin to the ileum of the pigs were 0.06, -0.03, -1.23, 0.18, 0.82, 0.12 and 0.95 for the diets containing wheat (var. Banks), wheat (var. Egret), sorghum, barley, meat meal, soya-bean meal and casein respectively. The same diets were given to 168 chickens. Digesta were collected from the terminal ileum after 7 d. The apparent digestibilities of biotin to the ileum of the chickens were 0.11, −0.10, −0.73, 0.05, 0.69, 0.28 and 0.75 for the diets containing wheat (var. Banks), wheat (var. Egret), sorghum, barley, meat meal, soya-bean meal and casein respectively.
