摘要 :
Brazilian systems for raising bullfrogs (concrete enclosure, concrete enclosure with feed dispenser and shelter, flooded enclosure) do not use enough water to keep temperature stable, and the low rate of water renewal hinders wate...
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Brazilian systems for raising bullfrogs (concrete enclosure, concrete enclosure with feed dispenser and shelter, flooded enclosure) do not use enough water to keep temperature stable, and the low rate of water renewal hinders water quality. In this article we propose raising frogs in cages placed in fish ponds having high thermal stability. The experiment consisted in evaluating the productive performance of bullfrogs housed in 1 m3 cages at the densities of 28, 56 or 84 animals/cage, fed a ration delivered by an automatic dispenser. Each pond was 72 m2 large. Two fish densities were used (200 or 300 tilapias/pond). The experimental period lasted 105 days for tilapias (May-August) and 60 days for frogs (July-August). No significant differences among densities were observed for frog performance. Using 200 tilapias/pond improved fish weight gain and dissolved oxygen concentration, as compared to 300 tilapias/pond. This new rearing system provided an adequate environment for frogs, as there was weight gain and zero mortality during winter.
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