注記 |
A study on the effect of water salinity ranging from 0 ppt to 30 ppt on the hatching success of climbing perch, Anabas testudineus, was conducted in a 15–liter glass aquarium (water volume 10 liters) containing 100 eggs. Fertilization rates at 0, 5, 10, 15, 20, 25, and 30 ppt were 76.67, 61.33, 77.00, 47.33, 1.67, 0.33, and 0%, respectively. The fertilization rate at 0–10 ppt did not change. When the water salinity increased, the fertilization rate decreased. Hatching rates at 0, 5, 10, 15, 20, 25, and 30 ppt were 91.33, 87.90, 86.20, 77.49, 0.00, 0.00, and 0.00%, respectively. The hatching rate at 0–10 ppt was significantly (P < 0.05) higher than that at 15, 20, 25 and 30 ppt. The times (1,255–1,300 minutes) of hatching out among water salinity of 0–15 ppt did not change. The survival tolerance of climbing perch larvae in different water salinities (0–30 ppt) within 24 hours was then studied using a 50–liter glass aquarium (water volume 30 liters) containing 50 larvae at each level of water salinity. All treatments were done in triplicate. The survival rates of fish larvae in 0, 5, 10, 11, 12, 13, 14, 15, 20, 25, and 30 ppt were 100, 100, 100, 83.3, 83.3, 73.3, 70, 70, 0, 0, and 0%, respectively. The survival rates at water salinities of 0–12 ppt were not significantly different. The gain rate of total body length at 8 weeks at water salinities of 0, 5, 10, 11, and 12 ppt were 1.77, 1.41, 1.36, 1.36, and 1.63 cm, respectively. The gain rates of total body length at 0–12 ppt were not significantly different. We conclude that water salinity in the range of 0–12 ppt is suitable for climbing perch culture.
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