OPTIMUM WATER TEMPERATURE FOR THE GROWTH OF JUVENILE COMMON CHINESE CUTTLEFISH, SEPIELLA MAINDRONI (DE ROCHEBRUNE 1884)

摘要

The current study was carried out to investigate the influence of water temperature on growth and activity of the digestive enzymes pepsin, trypsin, lipase, and amylase in common Chinese cuttlefish (Sepiella maindroni de Rochebrune). Triplicate groups of S. maindroni (weight +/- SD, 4.08 +/- 0.26 g; mantle length, 31.37 +/- 1.04 mm) were reared at different water temperatures (16 degrees C, 20 degrees C, 24 degrees C, 28 degrees C, and 32 degrees C). S. maindroni instantaneous growth rate (IGR), feeding rate (FR), food conversion (FC), and mantle length increase (ML) were significantly affected by water temperatures. Regression relationships between water temperature and IGR = -0.026T(2) + 1.359T - 12.63 (n = 15, R-2 = 0.995); FR = -0.064T(2) + 3.465T - 25.69 (n = 15, R-2 = 0.971), FC = -0.069T(2) + 3.55T - 25.01 (n = 15, R-2 = 0.983); and ML = -0.238T(2) + 12.27T - 123.9 (n = 15, R-2 = 0.992). The optimum temperatures for IGR, FR, FC, and ML were 26.13 degrees C, 27.07 degrees C, 25.72 degrees C, and 25.78 degrees C, respectively. Survival was greatest at 24 degrees C and 28 degrees C (>95%), and was significantly higher than other temperatures. Digestive enzyme activities were highest at 24 degrees C or 28 degrees C, and were significantly higher than at 16 degrees C. In conclusion, the optimum temperature for growth of S. maindroni is 25-27 degrees C based on IGR, FR, FC, and digestive enzyme activities at different temperatures.