The Effect of Diet and Cecectomy on the Intestinal Synthesis of Biotin in Mature Fowl

THE need for biotin in reproduction of the domestic fowl was established by Cravens, Sebesta, Halpin and Hart (1942). The abnormalities of biotin deficient embryos have been described by Cravens, McGibbon and Sebesta (1944) and Couch, Cravens, Elvehjem and Halpin (1948a). Couch, et al. (1948b) reported that dextrin favored the intestinal synthesis of biotin while sucrose did not favor such synthesis. Johansson, Sarles and Shapiro (1948) reported that the cecum was found to be the site of the greatest concentration of intestinal microorganisms in mature chickens. Preliminary investigations made in an attempt to establish the site of synthesis revealed that the ceca contained about ten times as much biotin and two times as much riboflavin and niacin as the duodenum loop, the small intestine, or the feces excreted. Couch, et al. (1949) reported that folic acid was found to be about six to eight times as high in the ceca . . .