温度对半滑舌鳎的生长、生化组成和能量收支的影响

研究了不同温度(16,19,22,25,28和31 ℃)对半滑舌鳎(Cynoglossus semilaevis Günther)幼鱼的生长、体成分组成和能量收支的影响.结果表明,随温度的升高,半滑舌鳎幼鱼生长率总体呈现先升高后降低的趋势.其中,在19～25 ℃温度范围内,半滑舌鳎幼鱼的特定生长率相对较高,在16和28 ℃下则有所降低,而在31 ℃下,半滑舌鳎幼鱼特定生长率则显著降低.本研究表明半滑舌鳎幼鱼特定生长率与温度符合二次曲线模型.半滑舌鳎摄食量随温度升高而逐渐增大,但在31 ℃时显著减小,饵料转化率则随温度的升高而降低.鱼体脂肪与能值均随温度升高而降低,蛋白质含量受温度影响不显著.温度对半滑舌鳎的能量收支影响显著,其中,生长能和代谢能主导半滑舌鳎的能量分配,生长能占摄食能比例则随温度的升高而降低,呼吸能占摄食能比例则随温度的升高而升高.本研究表明,半滑舌鳎幼鱼(13～37 g)适宜生长温度范围为18～25 ℃,而不同温度导致的半滑舌鳎摄食量和能量收支的差异可能是温度影响其生长的主要生理生态学机制.

Effects of Temperature on the Growth, Biochemical Composition and Energy Budget of Tongue Sole,Cynoglossus semilaevis Güther

The influence of temperature(16, 19, 22, 25, 28 and 31 ℃) on the growth, biochemical composition and energy budget was investigated in juvenile tongue sole(Cynoglossus semilaevis Güther). The results showed that the specific growth rate of tongue sole increased with the increase of temperature from 16～25 ℃ and then decreased at 28～31 ℃. The relationship between specific growth rate of juvenile tongue sole and temperature was described as quadratic. Lipid and energy contents of dry body decreased with increasing temperature, while crude protein content was not significantly affected by temperature. The effects of temperature on the energy budget of juvenile tongue sole were significant. Energy assimilated in growth and those consumed in respiration dominated the mode of the energy allocation of juvenile tongue sole. The proportion of food energy allocated to respiration increased with increasing temperature. However, those assimilated to growth decreased with increasing temperature. The present study revealed that the suitable temperature of juvenile tongue sole was 18～25 ℃. The mechanism of temperature effect on the growth of tongue sole may be ascribed to the differences of food consumption and energy budget resulted from different temperatures.