dc.description.abstract | 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°C, the following experimental treatments were applied: temperatures of 23.0, 26.0, 29.0, 32.0 and 35.0°C per 30 days for frogs with 100 g initial LW; 24.5, 26.0, 27.5, 29.0, 30.5, and 32.0°C, also on 30 days, for frogs with 20 g initial LW; and the combination of the temperatures of 26.0 and 29.0°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°C frogs with 100 and 20 g initial LW, respectively, with the highest growth at 28.2°C, for frogs of 100 g initial LW and at 29.7°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. | |