Alabama catfish farmers’ checkoff dollars are paying dividends thanks to ongoing research at Auburn University (AU) that’s causing farmers to significantly change their catfish feed to prevent disease.

Since 2015, researchers have studied whether a fish-feed additive can break the disease cycle caused by a strain of the bacterium Aeromonas hydrophila. Initial trials on three west Alabama farms indicate the additive improves catfish health and production.

“This trial is already helping our farmers save money,” said Rick Oates, the Alabama Farmers Federation Catfish Division director. “The additive is growing better fish and cutting down on loss late in the growing season.”

Aeromonas first appeared in Alabama in 2009 and can kill up to 75 percent of fish in affected ponds in a few days, usually right before harvest.

When fish don’t absorb phytate, which is in plant-based feed, phosphorous accumulates in ponds, potentially leading to aeromonas growth. The research explores the relationship between plant-based diets and phytate’s effect on aeromonas. Researchers worked with a major Alabama feed mill to spray a phytate enzyme on the feed to combat phytate in ponds. 

In 2016, almost all catfish feed in Alabama contained phytate for the first time, said Eric Peatman, the study’s lead scientist.

“In our pond studies last year, fish grew faster and about 20 to 23 percent larger,” said Eric Peatman, AU School of Fisheries, Aquaculture and Aquatic Sciences associate professor. “And they had a better feed-conversion ratio.”

Harvest results appear consistent, too, with performance gains and improved blood work.

Peatman calculates the additive costs $4-6 per ton, a small price compared to benefits for farmers. He said the additive may not end aeromonas, but is a step in the right direction.

Alabama’s catfish checkoff helped fund the research. The checkoff is $1 per ton of catfish feed sold. It generates more than $120,000 annually.

Catfish production has a $158.2 million economic impact each year in Alabama.