نبذة مختصرة : The effect of stocking density on growth and survival rate of Bullfrog (Rana catesbeina) tadpoles in concrete tank (90 cm diameter and 20 cm of water level) with 80% shading was studied. The one week-old tadpoles with average weight of 0.12 g were stocked at 3 stocking densities of 60, 120 and 240 individuals/tank for 20 days. They were fed to apparent satiation with 40% protein at 10% of body weight twice a day. The result indicated that tadpoles developed two legs at 18 days and four legs at 28 days. The mean weights gained by the experimental tadpoles were 1.45+0.03, 1.24+0.05 and 1.06+0.03g, respectively. The average daily weights gained by experimental tadpoles were 0.073+0.001, 0.062+0.003 and 0.053+0.001 g day-1, respectively. The specific growth rates of experimental tadpoles were 12.86+0.08, 12.12+0.19 and 11.42+0.13 % day-1, respectively. The results indicated that at the end of the experiments, growth of the tadpoles was significantly different among 3 stocking densities (P<0.05), with the survival rates of 31.11+1.92, 21.94+1.27 and 17.78+0.87 %, respectively (P<0.05).
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