Received: 20-06-2017 / Accepted: 10-08-2017
This study was conducted to evaluate the effects of different stocking densities on growth and survival rate of black apple snail, Pila polita. There were 4 stocking densities and 3 replicates per treatment as follow: 50, 100, 150, 200 ind./m2. Snails with initial weight (1.6 g), shell height (20.7 mm) and shell width (14.3 mm) were reared in hapanetand fed 50% pellet (Proconco, 18% protein) + 50% vegetable (spinach, 3.4% protein). After 4 monthsof culture, at low stocking densities, the survival rate was higher than that of high density treatments (77.4, 75.6, 73.8 and 68.5% at density 50, 100, 150 and 200 ind./m2, respectively with) (p <0,05). Rearing at 50 ind./m2, snails reached highest body weight, shell height and shell width (31.09 g; 54.90 mm and 43.38 mm, respectively) compared to 100 ind./m2(30.65 g; 53.42 mm and 43.14 mm), 150 ind./m2(30.03 g; 53.61 mm and 42.32 mm) and 200 ind./m2(28.35 g; 53.09 mm và 41.41 mm). At the stocking density of 50 ind./m2snails also hadlowest FR (2.62). It was similar to the density of 100 ind./m2(2,80) and significantlydifferent(p <0.05) compared to 150 ind./m2(3.04) and 200 ind./m2(3.45). Snails raised at 50 ind./m2yieldedthe highest profit (19.535 VND/m2),followedby 100 ind./m2(18.122 VND/m2) and was significantlydifferent(p <0.05) compared to 150 or 200 ind./m2(10.487 - 14.280 VND/m2). The results from this study provide the basic information for further studies to develop culture techniques for Black apple snailculturein the Mekong Delta.