Effects of L-proline on swimming parameters of Daphnia magna subjected to heat stress.

L-proline (L-PROL) is an essential amino acid, a constituent of many proteins and the osmoprotective molecule produced and accumulated in higher plants and some freshwater microalgae in response to various environmental stressors. Knowledge on thermoprotective effects of this amino acid on freshwater invertebrates is very scarce. Therefore the aim of our study was to determine the effect of L-PROL at concentrations: 10 mg/L, 20 mg/L and 50 mg/L on swimming behavior (immobilization, swimming track density, swimming speed, turning ability) of Daphnia magna subjected to temperatures: 22 °C, 35 °C and 38 °C.