Catfish industry embraces USDA pond management research

Jan 27, 2014 by Sandra Avant
ARS scientists have calculated the dissolved oxygen level that catfish need for growth, giving producers an objective management measure rather than having to rely on when the fish are observed at the surface in distress. Credit: David Nance.

The aquaculture industry is taking notice of U.S. Department of Agriculture (USDA) research that gives the precise levels of dissolved oxygen needed to keep pond-raised catfish alive and growing.

Traditionally, fish farmers relied on daily observations to determine if fish were getting enough . If farmers saw fish sucking air at the water surface, they turned on aeration equipment. If no fish were seen, it was assumed that enough oxygen was being provided.

Les Torrans, a fish biologist in the Agricultural Research Service (ARS) Warmwater Aquaculture Research Unit in Stoneville, Miss., pinpointed the concentrations needed to keep fish alive and growing. ARS is USDA's principal intramural scientific research agency.

Dissolved oxygen is the most critical water quality factor in aquaculture. If oxygen gets too low, fish can die or become partially asphyxiated. Lack of air causes fish to lose their appetite. When they eat less, they do not grow as quickly. As a result, instead of fish reaching market size in two years, it may take four to five years.

Torrans, together with his ARS and Mississippi State University colleagues at the Thad Cochran National Warmwater Aquaculture Center in Stoneville, studied the effects of dissolved on catfish growth, yield, food consumption and feed conversion.

An oxygen monitoring system was used to maintain precise minimum dissolved oxygen setpoints—3.0, 2.0 and 1.5 parts per million (ppm). Results showed that the minimum dissolved oxygen concentration for optimum production is 2.5 to 3.0 ppm. At this level, catfish growth significantly improved, fewer fish died, feed conversion improved and the production cycle was shorter.

Farmers who use good oxygen management practices can double the growth rate of fish, according to Torrans. The exact amount of aeration needed to maximize food intake, growth and production is now available.

Explore further: Breeding hybrid catfish

More information: Read more about this research in the November/December 2013 issue of Agricultural Research magazine.

add to favorites email to friend print save as pdf

Related Stories

Breeding hybrid catfish

Dec 06, 2013

In the catfish industry, it's well-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 ...

Helping fish get rid of the 'Ich'

Oct 28, 2010

Copper sulfate has emerged as an effective treatment for Ichthyophthirius multifiliis, also known as "Ich," a protozoan parasite that appears as white spots on infected fish, according to a U.S. Department of Agriculture ...

Understanding oxygen depletion on the Oregon coastal shelf

Oct 09, 2013

Each spring, the winds off Oregon shift, changing ocean currents and spurring the onset of the upwelling season, an approximately 4 month period where cold, nutrient-rich, oxygen-depleted deep water is driven into the coastal ...

Nevada marina deemed safe despite 100K fish kill

Jan 19, 2014

Though testing is incomplete, state officials say they're convinced a Nevada marina where an estimated 100,000 trout, bass and catfish died poses no danger to humans or animals.

Recommended for you

Dwindling wind may tip predator-prey balance

Sep 19, 2014

Bent and tossed by the wind, a field of soybean plants presents a challenge for an Asian lady beetle on the hunt for aphids. But what if the air—and the soybeans—were still?

Asian stars enlisted to fight African rhino poaching

Sep 19, 2014

Increasingly desperate South African conversationists are turning to a multi-national team of "rhino ambassadors" to try to end the scourge of poaching—and Vietnamese pop diva Hong Nhung has been recruited ...

Tropical fish a threat to Mediterranean Sea ecosystems

Sep 18, 2014

The tropical rabbitfish which have devastated algal forests in the eastern Mediterranean Sea pose a major threat to the entire Mediterranean basin if their distribution continues to expand as the climate ...

User comments : 0