Heterozygosity and Oxygen-Consumption Rate as Predictors of Growth and Developmental Rate in Rainbow Trout

Abstract

A significant positive association between body length and multiple-locus heterozygosity is reported in a strain of rainbow trout (Salmo gairdneri). There is also a significant negative association between the number of heterozygous loci per fish and oxygen-consumption rate. Although more heterozygous fish use less oxygen, the amount of variation explained by this relationship is small. No significant association between oxygen consumption and hatching time is evident, although fish in genotypic classes that had faster average developmental rates tended to use less oxygen. These results suggest that faster developmental and growth rates may be attributed partially to the greater metabolic efficiency of more heterozygous fish.