Location: Warmwater Aquaculture Research UnitTitle: Influences of cyclic, high temperatures on juvenile channel catfish growth and feeding Author
Submitted to: North American Journal of Aquaculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/12/2012
Publication Date: 12/7/2012
Citation: Arnold, M.B., Torrans, E.L., Allen, P.J. 2012. Influences of cyclic, high temperatures on juvenile channel catfish growth and feeding. North American Journal of Aquaculture. 75(1):77-84. Interpretive Summary: We studied the effects of high temperatures on juvenile channel catfish to determine their vulnerability to heat stress in southern commercial catfish ponds. High temperatures may be a problem during unseasonably warm weather and may occur more frequently with climate change. We found that juvenile channel catfish are susceptible to warm temperatures. Feed intake, growth, and survival decreased, whereas activity increased at high temperatures. Therefore, increases in temperature present challenges to commercial catfish culture.
Technical 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 (23-27ºC, 27-31ºC, and 31-35ºC) characteristic of culture 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 total length (TL) were measured in fingerling channel catfish over an eight week period in a flow-through, multiple-tank system. Specific growth rate, feed consumption, TL, and wet weight increased significantly in the 27-31ºC treatment in contrast to the 23-27ºC and 31-35ºC treatments. Feed conversion ratio was lowest in the 27-31ºC treatment whereas activity levels were highest in the 31-35ºC treatment. Survival significantly decreased for catfish in the warmest treatment compared to 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.