Differences in the growth patterns of fry among chum salmon Oncorhynchus keta families

Abstract

Twenty-five chum salmon Oncorhynchus keta families were produced using a 5×5 diallel mating design, and the body weights and specific growth rates (SGRs) were measured from 0 to 99 days after emergence. The body weights of the fry differed in the same developmental stages among the families. In addition, the mean body weights of fry that originated from small eggs were low, but their SGRs were high. These results suggest that the body sizes of chum salmon fry are strongly governed by the initial egg size, but that their body size and growth rate at each developmental stage vary depending on the combination of sire and dam.