Levels of metabolizable energy for rations of bull frog

Abstract

The objective of the present study was to evaluate the effects of the interaction among the level of gross protein (GP)/metabolizable energy (ME), in the ration of the frogs through the acting of the animals (win of weight, alimentary consumption, alimentary conversion). Five rations were formulated with 40% of PB and five levels of EM (2300; 2400; 2500; 2600; 2700 kcal kg^-1 of ration), supplemented with oil. The experimental design was completely randomized blocks, with five treatments and four repetitions and twenty-five animals for experimental unit. The initial weight was of 13.0 g í  17.0 g; 17.1 g í  21.0 g; 21.1 g í  25.0 g; 25.1 g í  30.0 g, in the blocks 1, 2, 3, and 4 respectively. The feeding was supplied "ad libitum" with 10% of fly larvae up to the thirtieth day, and with 5% from the thirtieth day onwards. The ration consumption was not affected by the level of the ration. The consumption of energy of the ration had the same behavior of ration consumption, with a tendency of larger consumption of energy for the level of 2,500 kcal/kg. The difference between the largest consumption of energy and the smallest one was of 15.21%, and this difference for the ration consumption was of 12.07%. The alimentary conversion did not vary among the levels. The carcass revenue was not influenced by the level of ME in the ration. The frogs that received ration with a level of 2,400 kcal/kg presented a value of the relationship hepatosomatic superior at the level of 2,600 kcal/kg. There was an increase of the liposomatic relationship when increased the level of ME.