Production of all-female rainbow trout (Oncorhynchus mykiss) using sex-reversed males and investigation of their growth parameters in the first year of culture

Possibility of producing all-female rainbow trout (Oncorhynchus mykiss) using neomale stock were investigated in Kelardasht hatchery. To do this, we compared the fertilization, hatching rate and growth parameters of progeny in the first year of culture. Histological studies of gonads showed that progenies produced by mating sex-reversed males and normal females were totally female. Eyed-stage egg, hatching and early survival rate in all of female population were 90:69 %, 97.36 %, 91.49 % and in mix sex population were 7024 %, 98.22 %, 90.73 %, respectively, showing no significant differences (P>0.05). Lack of maturation in the first year cultured fish led to the identical growth parameters in mix sex and all-female groups (P>0.05). Results showed that use of sex-reversed males can be one of the best and successful methods of producing all-female populations