中文摘要：

以初始体重（118.42±4.38）g的黄鳝（Monopterus albus）为对象,利用网箱研究越冬（时间为2012年11月20日至2013年3月25日）对黄鳝形体、肠道消化酶及部分生理生化指标的影响。试验结果表明,越冬后黄鳝的平均体重、脏体比显著下降,降幅分别为6.50%、19.84%;肝体比极显著下降,降幅32.93%;越冬对黄鳝的肥满度无显著影响。越冬显著降低黄鳝肠道胰蛋白酶活力,降幅46.37%;淀粉酶和脂肪酶活力虽下降,但不显著。越冬极显著降低了黄鳝血清中过氧化氢酶活力,降幅66.19%;显著降低了溶菌酶活力,降幅29.59%;血清中丙二醛含量虽有下降,但不显著;血清中补体C3活力极显著上升,升幅28.57%;补体C4无显著影响。越冬显著影响黄鳝形体指标,越冬期间黄鳝主要消耗自身储备来维持血糖水平提供能量,并通过降低过氧化氢酶、溶菌酶和肠道胰蛋白酶活力和提高补体C3活力达到免疫平衡。

英文摘要：

Fish metabolism responds to the low temperature and threat of starvation during overwintering. Monopterus albus is a commercially valuable benthic fish inhabiting subtropical freshwater. The species is vulnerable to numerous diseases and the mortality rate is high during and for a time after overwintering. However,changes in physiological function during overwintering are not clear and no research has been reported on the effect of overwintering on physiological and biochemical indices for Monopterus albus. In this study,differences in selected physiological and biochemical indices before and after overwintering were measured and the effect of overwintering evaluated to provide data necessary for healthy culturing of Monopterus albus. From November 20,2012 to March 25,2013（ 124 days） an experiment was conducted in net cages（ 1. 5 m × 2. 0 m × 1. 5 m） with 90% cover of Alternanthera philoxeroides. Three groups of 70 Monopterus albus with an initial average body mass of（ 118. 42 ± 4. 38） g were cultured in net cages. Before and after the trial,the Monopterus albus in each group were counted and weighed and the data was used to calculate death rate and change in body mass. Five individuals were randomly selected for measurement of body length,the condition factor（ CF）,hepatosomatic index（ HSI） and visceral index（ VSI）.Two more individuals were randomly selected for measurement of intestinal trypsin,lipase and amylase and another two Monopterus albus for measurement of serum catalase（ CAT）,lysozyme（ LZM）,malondialdehyde（ MDA） and complement components C3 and C4. While no significant difference was observed in the CF,the weight and VSI of Monopterus albus significantly decreased during overwintering（ P〈0. 05）,reduced by 6. 50% and 19. 84%,respectively,and the HSI displayed a highly significant decline（ P〈0. 01） of 32. 93%. The decrease in serum CAT activity was highly significant（ P〈0. 01） and the decrease in serum LZM and intestinal trypsin activities were sign