南方鲇摄食不同含量纤维素和草鱼肠后的代谢反应

Postprandial Metabolic Response in Silurus meridionalis Fed Diets with Different Levels of Cellulose and Grass Carp(Ctenopharyngodon idella) Intestine

[目的]研究鱼类生化SDA(特殊动力作用)和机械SDA的大小。[方法]在水温25℃条件下用草鱼肠衣(0.25 g)包埋的方法测定了南方鲇摄食不同含量(0.25、0.75和1.5 g)纤维素和能量(草鱼肠)后的代谢反应。[结果]摄食不同食物后南方鲇代谢出现先迅速上升然后缓慢回落的过程,食物纤维素导致SDA时间的延长和SDA总耗能量的增加,但不同纤维素组间没有差异,摄食代谢峰值不受食物纤维素的影响;随着摄食草鱼肠重量的增加SDA时间、摄食代谢峰值和SDA总耗能量均线性上升。[结论]南方鲇摄食代谢主要由生化SDA构成,与食物可利用能量密切相关而与体积相关不大。

Abstract The postprandial metabolic response in Silurus meridionalis fed diets with different levels （0.25, 0.75 and 1.5 g） of cellulose and grass carp intestine was investigated to determine the relative proportion of mechanical and biochemical specific dynamic action （SDA）. It was found that the metabolic rate was immediately increased after feeding and then slowly returned to pre-fed level. All diets with added cellulose shown larger SDA duration and energy expended on SDA compared to the control group. But there were no significant difference among different cellulose groups. However, SDA duration, energy extended on SDA and peak postprandial metabolic rate all linearly increased with increased dietary grass carp intestine. It suggested feeding metabolism in Silurus meridionalis was mainly biochemical SDA. The SDA was closely related with dietary energy but not the dietary volume although added cellulose elicited some mechanical SDA due to added energy cost associated with wiggle of alimentary tract. The metabolism of Silurus meridionalis is mainly consisted of biochenxical SDA, and is closely related to feed available energy and is not related to volume.