Absorption and Secretion of Fatty Acids and Bile Acids in the Intestine of the Laying Fowl

Individual fatty acids and bile acids absorption has been assessed in the laying hen, through the use of 91Y as a reference substance and microdeterminations of these compounds. A heavy secretion of lipid material containing mainly linoleic, palmitic and stearic acids occurred in the duodenum. Absorption followed throughout the entire intestine, but the rate in the jejunum was greater than in the ileum. The overall absorption of the individual fatty acids ranged between 82 and 94%. Dihydroxycholanic bile acids were secreted into the duodenum at a rate of about 8 g/day. Close to 93% of the secreted bile acids was absorbed by both jejunum and ileum. The concentration of these bile acids reached 70 mmoles/liter in the contents of the upper jejunum.