After a two-year search to hire a new research leader at the Catfish Genetics Research Unit, USDA-ARS, in Stoneville, Miss., a familiar name now holds the position.
Ken Davis, physiologist and most recently a researcher at the USDA National Aquaculture Research Center in Stuttgart, Ark., collaborated with peers on catfish research projects at the Stoneville laboratory shortly after it opened during the 1990s.
At that time, Davis was on faculty at the University of Memphis, where he had worked since 1969.
Davis, who officially started July 25, said his new administrative duties are simple: “It's to free researchers here from any administrative problems that keeps them from conducting research.”
In 2001, the laboratory, which employs 12 workers and oversees experiments on 91 ponds, finished cultivation of a faster-growing catfish labeled NWAC103.
That breed, Davis said, has received mixed reviews from commercial growers since its release, but has been adopted by many enthusiastic farmers and particularly food fish producers.
Now, researchers are busy working toward releasing a second breed, but with a multi-disciplined approach extending beyond producing a faster-maturing, larger fish.
“This time researchers are focusing on selection with better disease resistance and food conversion,” he said.
Other ongoing lab studies are to improve a catfish's dimension (also known as body composition), which relates to the percentage that can be filleted; genomics — identifying the molecular genes in catfish; determining water quality levels, such as appropriate oxygen percentages; and ways to manage algae problems.
For about 15 years, catfish producers have faced one persistent problem, particularly with channel catfish: a bacterial, viral disease that attacks in infrequent episodes.
“It's frustrating because we can't predict it, but there are new efforts to work on that issue,” he said.
Davis said it is difficult to pinpoint when a new breed will be ready for release to the public, noting that, “It takes time to thoroughly evaluate, it's a slow process.”
When a new breed is ready for release, USDA relies on aquaculture researchers and Extension agents at Mississippi State University.
Although USDA may not be as visible as other research agencies because it does not have Extension agents, Davis said, USDA researchers are not out of touch with fish farmers.
In fact, Davis insisted that just the opposite holds true.
“MSU is the vehicle we use to release new selections, but we retain a close sensitivity to farmers because we want to know what their problems are. We have no Extension agents, but some of our work is done on farms,” he said.
The industry is presently taking a closer look at ways to improve catfish growth rates and spawning success. So are USDA researchers.
“Those issues, if improved, would be really valuable to the industry right now,” he said.
Davis observed that catfish receives more research attention than any other single fish in the aquaculture industry because of its favorable characteristics.
“Catfish grow well, they reproduce well in a wide-range of temperatures, and they also can tolerate crowding,” he said.
Their composition also offers a high dress percentage compared to similar species, he added.
Davis's expertise centers on animal reproduction and gender control. Thus, another goal of his is to conduct research at the lab that will concentrate on finding ways to breed more male catfish over female because of the Y gender's propensity to grow larger in size.
While the disparity can be fostered by hormonal manipulation, it would be an advantage for farmers, in terms of input costs, to achieve it by crossing traits.
“There has been some research work done on this in the past, but it diminished. So this will be a re-initiation of it here,” he said.
e-mail: [email protected]