<;P>;PROBLEM TO BE SOLVED: To provide a growth-promoting agent for fowls, comprising a fish degradation product with a microorganism, and to provide a fowl feed compounded with the same. <;P>;SOLUTION: Provided are the growth-promoting agent for the fowls, including, as an active ingredient, a fish degradation product obtained by degrading various kinds of fishes including Percomorphi fishes or a crushed fish product obtained by crushing their bodies with Bacillus circulans HA12(FERM P-13428) strain, and the fowl feed containing the growth-promoting agent. <;P>;COPYRIGHT: (C)2010,JPO&INPIT