A vibrating feeder tray improves bullfrog production

Studies have developed techniques for bullfrog feeding in which movement of the food stimulates food intake in the absence of housefly larvae. We analyze a completely randomized design with two treatments (vibrating tray and linear feeder) in triplicate. A total of 1800 bullfrog froglets (Lithobates catesbeianus) (7.60 ± 0.59 g) were divided in six pens of 12 m2 and density 25/m2. Three fattening pens contained linear cement feeders (3.0 × 0.50 m) with a V-shaped bottom that crossed the pen longitudinally at each side of the pool containing commercial diet (40% crude protein) with added 5% housefly larvae. In the other three pens, six vibrating feeders trays (80 × 34 cm) per pen were arranged linearly, three at each side of the pool with commercial ration without housefly larvae. The productive performance of frogs was assessed by weight gain, feed intake, feed conversion, specific growth rate and survival by 90 days. We observed that bullfrog froglets receiving food in a vibrating feeder tray present better productive performance (weight gain, feed conversion and specific growth rate) than animals fed ration and housefly larvae in a linear feeder. This response can be related to the greater visual stimulus of the food by frogs fed in vibrating feeder trays, in which food had greater movement.