不同温度对草鱼C、N、P营养要素收支的影响

Effects of temperature on the C,N,P nutrient budgets of grass carp (Ctenopharyngodon idellus)

模拟草鱼养殖周期内的温度波动范围,研究了温度变化对草鱼C、N、P营养要素收支的影响。实验采用4个温度条件(15、18、24和30℃)培养草鱼,测定了不同温度处理组内草鱼C、N、P营养要素的收支情况。结果表明:温度对草鱼C、N、P营养要素收支具有显著影响。15℃处理组中,草鱼摄食率、排氨率、排磷率和排粪率分别为3.405 7、7.533 4、0.000 8和0.601 3 mg/h,显著低于其他处理组,在24℃处理组中,达到最大值,分别为10.442 0、18.995 6、0.001 7和1.647 0 mg/h。草鱼的耗氧率随温度的升高而增加,耗氧率和温度之间变化规律符合方程OR=0.005 9×T1.2532(R2=0.84)。15℃处理组中,C、N、P营养要素的生长余力分别为1.064 9、0.126 4和0.018 8 mg/h,显著低于其他处理组,在24℃处理组中,达到最大值,分别为3.402 8、0.397 1和0.071 8 mg/h。15℃处理组中,C、N、P营养要素的吸收效率分别为81.38%、83.05%和80.30%,显著低于24和30℃处理组。

The present experiment simulated the temperature fluctuation during the culture period of grass carp（Ctenopharyngodon idellus）to examine the effects of the changes in temperature on the budgets of C,N and P nutrients.Grass carp were cultured at temperatures of 15,18,24 and 30 ℃ and the processes of C,N and P budgets were examined.The results showed that C,N,P nutrient budgets of grass carp were significantly different between the 4 temperature groups（P〈0.05）.The feed uptake rate,nitrogen excretion rate,phosphorus excretion rate and fecal production rate of grass carp were 3.405 7,7.533 4,0.000 8 and 0.601 3 mg/h at 15 ℃,respectively,which were significantly lower than other groups（P〈0.05）,and reached the maximum values at 24 ℃,which were 10.442 0,18.995 6,0.001 7 and 1.647 0 mg/h,respectively.The oxygen consumption rate（OR）increased with increasing temperatures（T）following the formula OR=0.005 9×T1.2532（R2=0.84）.The scope for growth（SFG）of C,N and P of grass carp were 1.064 9,0.126 4 and 0.018 8 mg/h at 15 ℃,respectively,which were significantly lower than other groups（P〈0.05）,and reached the maximum values at 24 ℃,which were 3.402 8,0.397 1 and 0.071 8 mg/h,respectively.The absorption efficiencies of C,N and P of grass carp were 81.38%,83.05% and 80.30% at 15 ℃,respectively,which were significantly lower than the 24 ℃ and 30 ℃ groups（P〈0.05）.