A Complete Life-Cycle in the "Germ-Free' Bantam Chickèn

Abstract

AFTER Pasteur raised his classical question in 1885 about germ-free life¹, several investigators attempted to rear chickens under germ-free conditions^2–6. The longest of these experiments, conducted in these laboratories, lasted about five months⁶. We now report the completion of the life-cycle in ‘germ-free' chickens, that is, the successful rearing of chickens to maturity, the production and incubation of fertile eggs and finally the hatching of a young chicken, all in germ-free conditions. This is the second germ-free vertebrate which we have been able to carry through a complete life-cycle ; the first being the albino rat⁷. (The term ‘germ-free' is used because of historical precedence. It should be taken to mean that the animals are free from demonstrable living microorganisms. In itself the term is confusing because it is obvious that a fertile egg is not germ-free. The question of proper terminology is taken up in some detail in LOBUND Reports No. 2, which is now in the press.)