A COMPARISON OF THE EFFECTS OF THE EFFECTS OF 3 WATER-CIRCULATION REGIMES ON THE AQUACULTURE OF BULLFROG (RANA-CATESBEIANA SHAW) TADPOLES

A 15-week experiment was conducted with bullfrog (Rana catesbeiana) ta dpoles to determine the effects of three different water management st rategies in rearing tanks: static, a daily exchange (100%/day) and a r ecirculating system (900% exchange rate/day). Survival growth rate and feeding performance of tadpoles stocked at 3.5 individuals/1 were com pared among the three treatments. The static system gave the best resu lts in terms of survival (57.9%), percent total weight gain (1803%), d aily weight gain (6.919 mg/day) and SGR (2.34%/day), all of which were statistically greater than the corresponding values from the other tr eatments. The lowest performance was found in tadpoles reared in the r ecirculating system. These differences are attributed to a supplementa ry source of nourishment provided by microlage covering the bottom and walls of rearing tanks of the static system. In recirculating systems , flushing of feed could have been an important component contributing to inadequate nourishment.