The expertise was developed in the Fazenda Marta raniculture project, located in Tremembé parix in the State of São Paulo í Brasil. The aim was to verify the productive performance (growth, survival, feed conversion) of bulls, Lithobates catesbeianus, diet fed post-metamorphoseates containing different amounts of vitamin C and its performance depending on temperature. The animals were kept in 24 tanks of 2,0 x 1.0 m at an initial density of 50 animals per square metre. The following dietary supplementation levels have been tested: 0, 250, 500, 750, 1.000 and 2.000 mg of vitamin C kg-1 of ration. The experimental design was entirely casualised, with six treatments and four replicas. The assessed pari- metres were: feed consumption, weight gain, feed conversion and survival rate. The animals were weighed at the beginning of the experiment and every 30 days the ambient temperature was recorded daily. The percentage of feed consumption decreased, as the frogs grew, from 3,85 to 1.20 % of live weight and the ambient temperature fell from 28,0 to 20.1 °C. It can be concluded that there was no influence of vitamin C on the productive performance (growth, survival and feed conversion) of bull frogs in the fattening phase.