Survival of Germfree Rats without Vitamin A

Science  07 Feb 1969:
Vol. 163, Issue 3867, pp. 574-575
DOI: 10.1126/science.163.3867.574


Weanling, germfree rats, transferred to a conventional animal room and fed a vitamin A-deficient diet, died in 23 to 54 days. In contrast, their littermates, kept germfree and on the same diet, survived for as long as 272 days. The rats kept in germfree conditions stopped growing after 1 to 4 months but responded to supplements of retinoic acid.