Improving catfish through genetic research is a relatively new activity. Much of the improvement in the last 40 years in all phases of agricultural production, both plant and animal, has resulted from genetic selection and hybridization. Faster growth, higher yield, better feed conversion, and increased resistance to disease can all be improved through genetic manipulation.
Several universities in the Southeast are involved in catfish genetic research. Scientists are doing work in selection, strain identification and evaluation, cross-breeding, hybridization, ployploidy, sex reversing, and gene splicing. The results of this research are encouraging, and this type of research is expanding.
In general, domesticated strains of catfish have shown better growth rates than wild strains. The many domesticated strains vary in growth rates, body conformation (influences dress-out percentage), and resistance to disease. Crossbreeding has also shown some improvements in growth rates, spawning success, and disease resistance (attributable to hybrid vigor). Of course, not all strains or crossbreeds perform equally at different geographical locations.
Crossing female channel catfish with male blue catfish has produced improved growth, feed conversion, resistance to certain diseases, catchability by seining and angling, and higher dress-out as compared to pure channel catfish. However, production of the channel female X blue male hybrid can be difficult. The two species rarely spawn naturally when mated together, and they spawn inconsistently even when expensive hormone injections are used. Research is continuing so that this significantly improved fish will be available to producers in the future.
From a practical standpoint, producers should work with domesticated strains. If you buy your fingerlings, buy from a producer who is practicing mass selection or who is working with improved strains. If you produce your own fingerlings, know what strain you have, try mass selection of your fastest growing fish, try to obtain improved strains for crossbreeding, and, most importantly, do not inbreed.
For help in identifying strains and understanding genetic improvement techniques request: Circular 273, "Ancestry and Breeding of Catfish in the United States," and Southern Cooperative Series Bulletin 325, "Genetics and Breeding of Catfish." These publications are available from the Alabama Agricultural Experiment Station at Auburn University.
More information on producing catfish fingerlings can be found in Extension circular ANR-327, "Producing Channel Catfish Fingerlings" available from your county Extension agent or the Extension fisheries specialists.