PROBLEM TO BE SOLVED: To provide raw material which can inhibit visceral fat accumulation in cultured fishes, livestock, and pet animals without affecting the animals in their gain in weight and growth.SOLUTION: Visceral fat accumulation in rearing animals are inhibited by feeding raw material containing both anserine and creatine to the rearing animals in combination with feed or by feeding feed containing the raw material to the rearing animals. The combination ratio of anserine to creatine is 5.8 or more and less than 57:1 based on weight.