Growth, condition factor, and survival of juvenile channel (Ictalurus punctatus), blue (I. furcatus), and hybrid (I. punctatus × I. furcatus) catfish at moderate and high temperatures

Abstract Although hybrid catfish (Ictalurus punctatus × I. furcatus) now constitute about half of the industry production, few studies have assessed comparative growth and survival with other commercially important catfish. Growth assessment is particularly important at moderate to high temperatures because of the direct influence of temperature on ectothermic organisms and the increasing trend of warm to extreme environmental temperatures. Therefore, growth, condition factor, and survival of channel (I. punctatus), blue (I. furcatus), and hybrid catfish were compared following a 10‐week growth experiment at moderate (23°C) and high (33°C) temperatures in tanks. It was hypothesized that hybrid catfish would outperform channel and blue catfish in overall growth due of heterosis, and growth of all three fish types would be greater at moderate than high temperatures, which are above the range for optimal channel and blue catfish growth. Channel catfish had the greatest growth and were in better condition compared to blue and hybrid catfish over moderate and high temperatures. All treatments had an average survival over 89% other than blue catfish at 33°C, which had an average survival of 63%. Therefore, these results indicate growth and condition factor in channel, blue, and hybrid catfish diminish at high temperatures, and channel catfish may outgrow blue and hybrid catfish at moderate to high temperatures.