Hatchery And Growth Performance of Two Trout Pure Breeds, Salvelinus Alpinus And Salmo Trutta Fario, And Their Hybrid

Abstract

An allelic cross between Salmo trutta fario and Salvelinus alpinus was carried out under con- trolled hatchery conditions. Survival to the eyed stage was significantly lower for the hybrid than for both purebreds. There were significant differences in survival in the eyed and yolk sac stages and from fertilization to the first feeding (p<0.05) between the hybrid and the purebreds, while the differences between the purebreds were not significant (p>0.05). The hybrid did not display heterosis with respect to any hatchery property. During the first 45 days of nursing, there were significant differences between the purebreds and the hybrid in terms of weight gain, survival, feed conversion ratio and specific growth rate (p<0.05) with no significant differences between the purebreds (p>0.05). The hybrid was slightly heterotic (+1.69) with respect to survival how- ever no heterosis was observed in any other property to the first feeding stage.