抄録
Effects of density and group size on food intake and growth rate were studied with immature medaka.
Higher density reduced the growth rate in the groups of more than two fish. In the fixed density (300cm3/1 fish), the growth rate and the feed conversion efficiency increased with increase of group size up to six fish. No relationship was observed between the food intake and the group size.
The results of the present and previous studies imply that the growth rate increased with increase of group size up to six fish, because of increased feed conversion efficiency owing to decreased oxygen consumption per unit weight, although the food intake did not increase.
