The growth promoting activity of vitamin B12 in rats has been demonstrated by many workers. Earliest among them was Emerson (1949) who showed that the retarding effect of thyroid powder when given to rats was counteracted by oral administration or subcutaneous injection of vitamin B12. Since 1949 many others have demonstrated the beneficial effect of B12 in augmenting growth in the young of several mammalian and avian species. Bioassay procedures for the estimation of vitamin BB are based on the capacity of B12 to stimulate growth. Cheng and Thomas (1950) showed that not only was growth enhanced but also food efficiency was improved by injecting "protamonized" rats with vitamin B12.
Proceedings of the Iowa Academy of Science
©1952 Iowa Academy of Science, Inc.
Cheng, Edmund Wei-Kuang and Thomas, Byron H.
"Increasing the Retention of Nitrogen in Albino Rats through Vitamin B12 Administration,"
Proceedings of the Iowa Academy of Science, 59(1), 178-192.
Available at: https://scholarworks.uni.edu/pias/vol59/iss1/22