IN the U.S. catfish industry, it's known that hybrid catfish — a cross of the channel catfish with the blue catfish — generally have better growth, higher survival rates and better meat yield than purebred channel catfish, according to the U.S. Department of Agriculture's Agricultural Research Service (ARS).
Although production has increased from 30 million hybrid fry in 2007 to about 150 million in 2012, these fish are not easy to breed, ARS said, noting that using hybrids instead of channel catfish could increase production by 20-30%.
Producers are now getting help from ARS researchers on learning how to produce these hybrids.
Unlike channel catfish that spawn naturally, the hybrid catfish is a cross between two species that rarely mate with each other. Hybrid fry production involves hormone-assisted reproduction.
ARS geneticists Brian Bosworth and Nagaraj Chatakondi at the ARS Warmwater Aquaculture Research Unit in Stoneville, Miss., worked with Mississippi State University colleagues at the Thad Cochran National Warmwater Aquaculture Center to give hands-on training to farmers who are learning about the hybrid breeding process.
In addition, ARS scientists study catfish nutrition, genetics and management practices to produce a better catfish, whether it's channel, blue or hybrid. Research includes improving hybrid embryo production by determining the effects of the calcium content of the water on the hatching success of eggs and developing a method to identify poor-quality eggs before they hatch, ARS said.
Geoff Waldbieser, a ARS molecular biologist at Stoneville, is developing DNA markers for channel and blue catfish to determine genetic diversity, produce pedigree populations and identify markers associated with important traits like meat yield and disease resistance.
While great improvements have been made in catfish breeding, one goal is to conduct research to help U.S producers who are grappling with a slow economy, high feed costs and fish imports from foreign countries, ARS said, noting that studies are under way to determine desirable heritable traits, improve germplasm, identify crucial water quality factors and develop better production systems.