Vitamin B12, APF Concentrates, Dried Whey, Fish Solubles and Liver Fraction “L” in the Nutrition of the Mature Fowl ,

Abstract

From the results of this study it is quite apparent that vitamin B₁₂ is required for egg production in the domestic fowl. Egg production was improved by feeding dried whey and liver fraction “L,” by the injection of liver extract and by the feeding of a high level (5%) of an APF concentrate which is produced as a by-product in the manufacture of aureomycin. The above-mentioned products were therefore assumed to contain an unidentified factor which is required for egg production. The hatchability of eggs from hens fed the basal diet (soybean protein-sucrose) decreased decidedly during the first 4 weeks of the test and few chicks hatched after this time. The addition of dried whey alone failed to improve hatchability appreciably. The hatchability of eggs from hens injected with crystalline B₁₂ and of those from hens fed APF concentrates decreased decidedly after the 12th week of the test, indicating that the hens were depleted of a second factor over and above vitamin B₁₂ which is required for hatchability after the 12th week. The feeding of liver fraction “L” maintained hatchability throughout the test period, and this product is believed to contain a factor necessary for hatchability in addition to vitamin B₁₂. The presence of lesser amounts of this factor in other materials was demonstrated by feeding dried whey with APF concentrates and by feeding a high level (5%) of an APF concentrate which is produced as a by-profuct in the manufacture of aureomycin.