The Characterization and Activity of Protease Enzyme on Different Days of Tadpoles [Pelophylax ridibundus (Pallas, 1771)]

Abstract

In this study, protease enzyme activity of Pelophylax ridibundus (Pallas, 1771) tadpoles was determined during the larval period starting from 25 Gosner stage (1960). When the P. ridibundus tadpoles reached the 25 Gosner stage (1960) on the 22nd day, the sampling was continued until the metamorphosis was completed by sampling at 5-day intervals. Initial average weight and length of the tadpoles were 0.076 g and 6.42 mm, respectively. The tadpoles were fed with pellet feed the size of 2 mm and 39% crude protein content twice a day in the morning and afternoon. The differences in the protease activity between the 22nd day and the 62nd day of the metamorphosis were found statistically significant (P<0.05). It has been observed that the protease enzyme reached maximum level at the 32nd day. In the next stages, protease activity showed a tendency to increase and decrease up to metamorphosis. These results can be used as the basis for the most appropriate nutritional formulation for P. ridibundus in the larval stage.