摘要
The effects of temperature and pH on embryonic development and survival rate of newly hatched larvae of Epinephelus fuscoguttatus were discussed by single factor experiment method. Under a salinity of 31‰, fertilized eggs were incubated at different temperatures (17, 20, 23, 26, 29 (eontrol), 32, 35 ℃ ) and different pH values (5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.4 (control), 8.5, 9.0, 9.5 and 10.0), the development rate of fertilized eggs, hatching rate, deformity rate, survival rate of newly hatched larvae, and optimum temperature and pH ranges for embryonic development were recorded and analyzed. The results showed that the incubation period y required by fertilized eggs was in remarkably negative correlation with temperature x, y =4 017. 3x-15277 , R2 =0. 971 3. At 29 ℃, the hatching rate was the highest, up to 92.00% ; this temperature was corresponding to the lowest deformity rate of newly hatched larvae ( 1.09% ) ; corresponding effective accumulative temperature was also the lowest (437. 410 ℃ . h), and significantly different from other experimental groups (P 〈 0.05 ) ; but on the contrary, corresponding survival rates at 24 and 48 h reached, respectively, 88.03% and 82. 97% which were significantly different from other experimental groups ( P 〈 0.05). At the pH of 8.4 in the CK group and the pH of 8.5 of one experimental group, the embryonic development rates were the highest; con-esponding hatching rates of fertilized eggs were the highest, respectively, of 88.33% and 83.33% which were significantly different from other groups (P 〈 0.05) ; and corresponding survival rates at 24 and 48 h were the highest, and reached 90.84% and 85.03%, respectively. In the pH range of 8.0 - 8.5, the deformity rate of newly hatched larvae was 0. It was indicating that for embryonic development of E. fuscoguttatus, the suitable water temperature value was in the range of 17 - 29 ℃, the optimum value was in the range of 23 -29℃; and the suitable pH value was in the range of 6.5 -9.5, and the optimum value was in the range of 8.0- 8.5.
The effects of temperature and pH on embryonic development and survival rate of newly hatched larvae of Epinephelus fuscoguttatus were discussed by single factor experiment method. Under a salinity of 31‰, fertilized eggs were incubated at different temperatures (17, 20, 23, 26, 29 (eontrol), 32, 35 ℃ ) and different pH values (5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.4 (control), 8.5, 9.0, 9.5 and 10.0), the development rate of fertilized eggs, hatching rate, deformity rate, survival rate of newly hatched larvae, and optimum temperature and pH ranges for embryonic development were recorded and analyzed. The results showed that the incubation period y required by fertilized eggs was in remarkably negative correlation with temperature x, y =4 017. 3x-15277 , R2 =0. 971 3. At 29 ℃, the hatching rate was the highest, up to 92.00% ; this temperature was corresponding to the lowest deformity rate of newly hatched larvae ( 1.09% ) ; corresponding effective accumulative temperature was also the lowest (437. 410 ℃ . h), and significantly different from other experimental groups (P 〈 0.05 ) ; but on the contrary, corresponding survival rates at 24 and 48 h reached, respectively, 88.03% and 82. 97% which were significantly different from other experimental groups ( P 〈 0.05). At the pH of 8.4 in the CK group and the pH of 8.5 of one experimental group, the embryonic development rates were the highest; con-esponding hatching rates of fertilized eggs were the highest, respectively, of 88.33% and 83.33% which were significantly different from other groups (P 〈 0.05) ; and corresponding survival rates at 24 and 48 h were the highest, and reached 90.84% and 85.03%, respectively. In the pH range of 8.0 - 8.5, the deformity rate of newly hatched larvae was 0. It was indicating that for embryonic development of E. fuscoguttatus, the suitable water temperature value was in the range of 17 - 29 ℃, the optimum value was in the range of 23 -29℃; and the suitable pH value was in the range of 6.5 -9.5, and the optimum value was in the range of 8.0- 8.5.
基金
Supported by Special Fund for Construction of Hainan Key Laboratory and Engineering Technical Research Center(gczx2013005)
Special Fund for Technology Development by Scientific Research Institutes of Hainan Province(KYYS-2014-59)
Special Fund for Application Technology Development and Demonstration(ZDXM2015025)
Hainan Provincial-level Department Budget Project