Effect of Supplementary Biotin on Performance of Turkeys Fed Corn-Soybean Meal Type Diets

THAT biotin is an essential vitamin for the chicken hen has been known for over a quarter of a century (Cravens et al., 1942, 1944). Further work in the same laboratory (Couch et al., 1948a, 1949) demonstrated that the dietary requirement of the hen for biotin was modified by variable intestinal synthesis. Couch et al. (1948b) showed that the biotin content of the egg white or yolk was highly responsive to the amount of biotin in the diet and upon apparent intestinal synthesis. Waibel et al. (1952) found that dietary penicillin resulted in increased deposition of biotin and folic acid in egg yolk. The symptoms of biotin deficiency in young chickens and turkeys were described by Patrick et al. (1942) and include dermatitis, perosis, and retarded growth. They estimated the daily biotin requirement for poults as 5 mcg. during the first four weeks; this level was about two and one…