Combining Ability of Channel Catfish (Ictalurus punctatus) Females and Blue Catfish (Ictalurus furcatus) Males for Tolerance of Low Oxygen

Abstract

Catfish are the backbone of the aquaculture industry in the United States accounting for the majority of finfish production. The primary species cultured was channel catfish (Ictalurus punctatus), but that has changed as 50-70% of production is now the channel catfish female X blue catfish (I. furactus) male hybrid catfish due to its increased growth and disease resistance. Full-sib and half-sib channel catfish female X blue catfish male hybrid families were evaluated for tolerance to low oxygen. Family variation was observed and general and specific combining abilities were calculated. Dam general combining ability had the greatest influence on tolerance to low oxygen in regards to survival and sire general combining ability had the largest effect on time to death. Strain of channel catfish female and blue catfish male had strong effects on the tolerance of low oxygen parameters for hybrid catfish fingerling. Both selection of individual channel catfish females, blue catfish males and strains of the parent species for increased tolerance of low oxygen should result in channel catfish female X blue catfish male hybrids genetically improved for tolerance of low oxygen.