The Effect of Fasting on the Bacterial Flora of the Intestine of Fish

Abstract

Sixteen bullheads (Ameiurus nebulosus) and three speckled trout (Salvelinus fontinalis) were kept in complete starvation for periods of time varying from one to two months and seven to ten days respectively. They were then examined, by culture methods, for the presence of bacteria in the intestine. Fifteen bullheads and the three trout did not yield bacteria. A Pseudomonad was obtained, in small numbers, from the intestine of one bullhead. Three bullheads and two trout examined two hours after the last feeding yielded intestinal bacteria in large numbers. In non-feeding fish, bacteria are usually absent from the intestine.