The effect of age of males on the early growth of chum salmon fry

Abstract

To evaluate the effect of Male age and size on the early growth of chum salmon Oncorhynchus keta fry, a diallel cross was performed using 5 feMales (4 years old) and 9 Males (3 Males, 3 years old; 3 Males, 4 years old; and 3 Males, 5 years old). Further, heritabilities for body weight were estimated at each developmental stage. Although no significant relationships were detected between Male body weight and fry size, the body weight of fry from crosses using 5-year-old Males tended to be lower than that of fry from crosses using 3- to 4-year-old Males. In addition, heritability increased as the fry developed. These results suggest that the age of Males is one of the factors that influence the early growth of chum salmon fry.