温度对饥饿状态下南方鲇幼鱼氨氮排泄的影响

Effect of Water Temperature on Ammonia-N Excretion in Starved Juvenile Southern Catfish ( Silurus Meridionalis Chen )

于 2 0 0 0年 4月至 5月 ,测定了温度对饥饿状态下南方鲇幼鱼 (体质量 1 8 4～ 3 6 0g)的氨氮排泄的影响 .在 1 2 5℃ ,1 7 5℃ ,2 2 5℃ ,2 7 5℃和 3 2 5℃水温下 ,南方鲇的特殊体质量排氨率分别为 :1 83 ,3 86,5 52 ,7 3 7和 9 2 9mg/(kg·h) ,排氨率 (AN)与温度 (t)显著正相关 ,其回归关系可用幂函数或直线方程描述 ,分别为 :AN=0 0 2 85t1 67(n=4 0 ,r=0 90 2 ,P <0 0 1 ) ,或AN=-2 71 + 0 3 68t(n =4 0 ,r=0 851 ,P <0 0 1 ) 通过讨论认为 :温度升高促使南方鲇蛋白质分解代谢的强度增大 。

An experiment was conducted to evaluate the effect of water temperature on ammonia N excretion rates in starved juvenile southern catfish with 18 4～36 0 g of body weight, from April to May, 2000. The specific-weight rates of ammonia N excretion were 1 83, 3 86, 5 52, 7 37 and 9 29 mg/(kg h)at 12 5℃, 17 5℃,22 5℃,27 5℃ and 32 5 ℃, respectively. There was a significant correlation between the rate of ammonia N excretion ( A N ) and temperature ( t ). Itcan be described as: A \- N = 0 028 5 t \+\{1 67\} ( n =40, r =0 902, P <0 01), or A \- N =-2 71 + 0 368 t ( n =40, r =0 851, P <0 01), respectively. The discussion suggested that acceleration of protein catabolism in the fish body with increasing temperature resulted in increment of the rate of ammonia N excretion.