Transporte de Killifish (Hypsolebias Flagellatus): efeito do uso de sal e da alimentação prévia associado de transporte

Abstract

The term killifish is a generic classification of all species of oviparous fish of the order cyprinodontiformes. The annual killifishes have direct development or by diapauses. In despite, the ornamental interest and researches about transport of the genus Hypsolebias are still scarce. The objective of this study was to evaluate the survival and water quality in the individual transport of Hypsolebias flagellatus, by testing different concentrations of salt in water (experiment I) and evaluating different transport times associated with different diets (Experiment II). For experiment I, 40 maleof killifishes (weight of 1.38 ± 0.83 g), previously fed with ration containing 46% PB, were used. The following concentrations of salt in water were tested: 0 (control), 2, 4 and 6 g of salt / L, for 12 hours of simulated transport. The experiment was composed of 10 replicates per treatment in a completely randomized design.For experiment II, 30 males previously fed with ration (weight of 0.68 ± 0.27 g) and 30 previously fed with artemia nauplii (1.48 ± 1.00 g) were used. The animals were submitted to three different simulated transport times: 12, 24 and 48 hours. The experimental design II was completely randomized in factorial scheme (2x3) representing six treatments with 10 replicates. Animals from both experiments underwent a 24-hour fasting before starting transport. For experiment I the different salinities did not affect the survival of the animals during the 12 hours of transport and 96 hours after transportation, with survival being 100%. No differences (P> 0.05) were recorded in total ammonia, temperature and pH values. The values of dissolved oxygen were higher (P <0.05) in the transport containing 4 g of salt / L and lower in freshwater. For experiment II, the survival after the opening of the transport bags was also 100%. After 96 hours of storage in the tanks, mean survival was 78%, with no differences between treatments and their interactions (P> 0.05). For the pH, there was no effect of the transport time and the interaction between the factors (P> 0.05), being higher when the animals were previously fed with ration. The total ammonia values were higher (P <0.05) in the treatment with 24 hours of transport and previous feeding with artemia and in both treatments submitted to 48 hours of transport. Already, the values of dissolved oxygen were decreasing with the increase in transport time independent of the previous diet provided. For H. flagellatus males, anytested salinity may be used during transport and diets up to 48 hours.