Influences of Cyclic, High Temperatures on Juvenile Channel Catfish Growth and Feeding

Abstract

Effects of high summer temperatures on Channel Catfish Ictalurus punctatus are poorly understood, particularly for thermal regimes that mimic pond aquaculture conditions. Therefore, this study examined the effects of three cycling upper-range temperature regimes (23–27°C, 27–31°C, and 31–35°C) characteristic of aquaculture environments in the Mississippi Delta. Feed conversion ratio, feed consumption, specific growth rate, activity levels, survival, and overall growth in terms of wet weight and TL were measured in fingerling channel catfish over an 8-week period in a flow-through, multiple-tank system. Specific growth rate, feed consumption, TL, and wet weight of fish increased significantly in the 27–31°C treatment in contrast to the 23–27°C and 31–35°C treatments. Feed conversion ratio was lowest in the 27–31°C treatment, whereas activity levels were highest in the 31–35°C treatment. Survival significantly decreased for catfish in the warmest treatment compared with catfish in the coolest treatment. These results indicate that high temperatures decrease growth in Channel Catfish, largely due to reduced food consumption and feed conversion and increased levels of activity. Therefore, increases in temperatures, such as from climate change, present challenges to the culture and management of Channel Catfish.

Received April 30, 2012; accepted September 12, 2012

ACKNOWLEDGMENTS

We thank our funding source, the U.S. Department of Agriculture, Agricultural Research Service, for supporting this project. Additionally, we give sincere thanks to the Thad Cochran National Warmwater Aquaculture Center, the Department of Wildlife, Fisheries, and Aquaculture, and the South Farm Aquaculture Facility at Mississippi State University for providing assistance, opinions, advice, facilities, and additional support throughout the entirety of this research. Gratitude is also expressed to Drs. James Steeby, Craig Tucker, and Les Torrans for serving as committee members on this project. Furthermore, we thank the reviewers for their opinions and ideas provided during the submission process of this manuscript.