INTENSIVE PRODUCTION OF HYBRID CATFISH  

Les Torrans*, Brian Ott, and Craig Tucker
USDA-ARS Warmwater Aquaculture Research Unit
Thad Cochran National Warmwater Aquaculture Center
Stoneville, MS 38776 USA
Les.Torrans@ars.usda.gov

Economic analysis by UAPB scientists shows clearly that under certain fish price-feed price combinations, intensively aerated ponds are not only an alternative, but are the profit-maximizing technology. We have raised hybrid catfish at stocking rates of 20,000/acre with aeration rates up to 10 hp/acre, producing over 28,000 lbs/acre in 0.25-acre research ponds. While ammonia concentrations were generally elevated above low-density (5,000 fish/acre) control ponds, there was no significant impact on FCR (1.8 in both treatments), a primary measure of biological efficiency. However, individual growth rate (final fish size) was reduced from 2.2 lbs/fish to 1.6 lbs/fish at the higher density. A follow-up study was conducted in 2015 to determine the effect of high stocking rates on water quality parameters, growth, and production when minimum DO was similar and maintained above 3.0 ppm.

Hybrid catfish of equal average weights (56.8 lbs/1000) were stocked on April 2, 2015 in six unreplicated 0.25-acre ponds at rates of 6,000- 36,000 fish/acre and fed daily to practical satiation. Each pond had a total of 24-hp/acre of available aeration (three 2-hp paddlewheel aerators per pond) which was controlled to maintain a minimum daily DO concentration in excess of 3 ppm and similar among ponds.  Fish were sampled monthly to assess for parasites, disease, and pathologies related to water quality. Temperature and pH were measured twice daily and used to calculate free CO2; TAN, nitrite, nitrate, and chlorophyll α were measured weekly; alkalinity, volatile and non-volatile suspended matter, and bacterial nitrification rates were measured bi-weekly; chlorides and hardness were measured monthly. Salt was added periodically to maintain a minimum chloride concentration of 100 ppm

The ponds will be harvested in November when feeding ceases due to cold temperatures. All data will be presented.

This presentation is dedicated to the memory of Samuel "Bo" Manning, 1981-2015, our colleague at the Warmwater Aquaculture Research Center.