A commercial-scale, in-pond raceway system for Ictalurid catfish production

A commercial-scale, in-pond raceway system was constructed in 2007 on a commercial catfish fish farm in west Alabama. The in-pond raceway system was installed in a 2.43-ha earthen pond with an average depth of 1.67 m. A slow-rotating paddlewheel (1.17 revolutions per minute) installed in each raceway produced a water velocity of 0.026 m/s and a water flow rate of 9.3 m(3)/min. This flow rate was equivalent to an average water exchange for each raceway every 4.9 min (approximate to 12x/h). Each raceway was originally stocked with 12,000-30,000 advanced channel catfish (Ictalurus punctatus) and hybrid catfish (I. punctatus x Ictaturus furcatus) fingerlings weighing between 59.1 and 418.2 g to simulate a staggered stocking and harvest production schedule. During the 2008 production season, mean survival was 83.7% across all raceways. Growth rates ranged from 1.1 to 1.8 g/fish/day for channel catfish and from 1.6 to 2.2 g/fish/day for hybrid catfish. The average feed conversion ratio (FCR) for channel catfish and hybrid catfish was 1.74 and 1.36, respectively (range from 1.16 to 2.11) and 49,913 kg (20,540 kg/ha) of catfish were harvested. An additional 6365 kg (2619 kg/ha) of tilapia and paddlefish were harvested from the pond as co-cultured species. The results indicated a high potential for efficient production of catfish with other co-cultured species compared to traditional catfish culture practices in ponds. Design and engineering modifications need to be addressed in the future to improve the in-pond raceway system. (C) 2011 Elsevier B.V. All rights reserved.