The influence of the size of particles in the food upon the gain in weight in tadpoles of Rana catesbeiana Shaw, 1802, reared under intensive system

Abstract

In The experimental outdoor facility planned for intensive frog culture localized in the Fishculture Station of Pindamonhangaba (22°55'55"S and 45°27'22"W), São Paulo State, Brazil, the effect of the size of the particles in a ration (wheat meal) upon the gain in weight in tadpoles of Rana catesbeiana Shaw, 1802 was studied. The size of the particles was estimated by sieves with the following mesh sizes: 0.84 mm, 0.72 mm, 0.54 mm and 0.42 mm. During the experimental period (October, 6 through December, 2, 1983) the animaIs were kept in brick and cement tanks, all of the same dimensions. The experimental design was of an experiment in random blocks with four treatments and five repetitions. The treatments were: 0.78 mm; 0.63 mm; 0.48 mm and 0.21 mm in average. The analysis of variance taking into account the regression was significant for the component of the first degree (P<0.01). The treatment that showed the best gain in weight was 0.21 mm, i.e., the wheat meal containing the smallest particles.