Hybrid catfish (♀ channel catfish, Ictalurus punctatus × ♂ blue catfish, I. furcatus) account for ~60-70% of the catfish production due to superior performance compared to the parent species for several traits. Production of hybrid embryos is labor intensive and requires sacrifice of slow maturing blue catfish males. Xenogenesis has been utilized to produce hybrid catfish embryos more efficiently by transplanting unsorted gonadal cells from donor diploid blue catfish into triploid channel catfish fry. Then xenogenic channel catfish males are mated with normal female channel catfish to produce 100% hybrid progeny.
Normal channel catfish females were paired with normal males and putative xenogenic channel catfish males producing blue catfish sperm and induced to spawn in spawning enclosures in 2024. The reciprocal xenogenic female × normal male was also attempted. No reproductive differences were detected. Spawning percentage for normal ♀ × normal male ♂ (producing 100% channel catfish fry), normal ♀ × xenogenic ♂ (producing 100% hybrid fry), and xenogenic ♀ × normal ♂ (producing 100% reciprocal hybrid fry) was 60.0, 62.5 and 50.0%, respectively. Hatching percentage was 64.6, 62.8 and 69.3% for normal ♀ × normal male ♂, normal ♀ × xenogenic ♂, and xenogenic ♀ × normal ♂, respectively. Fry/kg ♀ BW was 3511, 2965, and 3338 for normal ♀ × normal male ♂, normal ♀ × xenogenic ♂, and xenogenic ♀ × normal ♂, respectively. In 2023 and 2024, spawning xenogenic males were given a second female to mate with and 0.0 and 62.5% were able to spawn twice in 2023 and 2024, respectively.
Xenogenic pairing to produce hybrids is as successful as channel catfish pairings, so this approach appears to be a viable option to make hybrid catfish embryos. We have also had success in developing a system that utilizes white catfish (Ameiurus catus) to produce channel catfish, blue catfish and hybrid catfish. To commercialize this approach, a step in the value chain, a company specializing in producing xenogenic males, would be needed. Economic analysis is needed to compare the cost/benefit of the traditional approach to making hybrids versus the xenogenesis approach. The xenogenesis approach can also be optimized further.