Influência da Temperatura da água no desempenho reprodutivo e diferenciação sexual do peixe Betta Splendenst

Abstract

The Betta splendens (beta) ornamental fish species has economic importance for Brazilian ornamental aquaculture. For ectothermal animals, such as fish, water temperature has important influence on biochemical and physiological processes. The objective of the present study was to evaluate the influence of water temperature on reproductive performance, survival, zootechnical performance in the first 30 days after hatching and sexual differentiation of B. splendens fish. The experimental design was 5 treatments (water temperatures 26, 28, 30, 32 and 34ºC) and four replications. After the period of adaptation of the 20 day breeders to the experimental temperatures, the animals were placed to mate. After spawning and hatching of the eggs, the larvae were kept in the aquariums where the spawning took place until the sexual identification of the animals. At the temperature of 34ºC no spawn success was obtained for the species. There was no significant difference in the number of larvae and weight gain with the increase in temperature. Survival presented a quadratic behavior with the increase in temperature, as well as the total length, where performance was highlighted in the temperatures of 28 and 30ºC. In relation to the number of males, this was higher in the higher water temperatures. The temperature of the water influences the reproductive, zootechnical performance and sexual differentiation parameters for B. splendens species.