Temperature effect on performance of bull-frog (Rana catesbeiana Shaw, 1802)

This study was carried out to evaluate the environmental effects on bull-frog (Rana catesbeiana Shaw, 1802) performance, raised in fiber glass cages installed inside acclimatized incubators. After an initial period of 15 days of adaptation, at constant temperature of 25.0 degrees C, the following experimental treatments were applied: temperatures of 23.0, 26.0, 29.0, 32.0 and 35.0 degrees C per 30 days for frogs with 100 g initial LW; 24.5, 26.0, 27.5, 29.0, 30.5, and 32.0 degrees C, also on 30 days, for frogs with 20 g initial LW; and the combination of the temperatures of 26.0 and 29.0 degrees C with the photo periods of 8, 12 and 16 h of light at every 24 hours, for frogs with 100 g initial weight. By deriving the regression equations that explain the temperature effects on the frogs performance, the highest weight gain was estimated at 27.6 and 30.1 degrees C frogs with 100 and 20 g initial LW, respectively, with the highest growth at 28.2 degrees C, for frogs of 100 g initial LW and at 29.7 degrees C, for frogs of 20 g initial LW. Temperature interacted with photoperiod in their effects on weight gain and body growth, weight and carcass yield, feed intake and feed:gain ratio.