投喂水平对黄鳝(Monopterus albus)生长、肠道消化酶活性及部分血清生理生化指标的影响

为探究不同投喂水平对黄鳝(Monopterus albus)生长、肠道消化酶活性及血清生理生化指标的影响,分别以初始体重为(68.85±0.44)g和(26.67±0.17)g的2种规格黄鳝为研究对象,大规格按照体重的2.8％、3.6％、4.4％和5.2％投喂;小规格按照体重的3.0％、4.0％、5.0％、6.0％和7.0％投喂;每个处理组设置3个重复,大规格组50尾/箱,小规格组100尾/箱,实验持续56d.实验结果显示,随着投喂水平的增加,2种规格黄鳝增重率、饲料系数、肝体比以及全鱼脂肪含量都显著升高(P＜0.05),但金鱼蛋白含量呈下降趋势.大规格黄鳝在投喂水平为4.4％和5.2％时增重率达到最高水平,且组间差异不显著(P＞0.05);大规格黄鳝肠道脂肪酶和胰蛋白酶活性随投喂水平的增加而显著升高(P＜0.05);大规格黄鳝血清超氧化物歧化酶(SOD)活性、总胆固醇(TC)含量先升后降,血清甘油三脂(TG)含量呈上升趋势;大规格黄鳝在投喂水平为4.4％时,SOD和溶菌酶(LZM)活性达到组间较高水平.随着投喂水平的增加,小规格黄鳝肠道胰蛋白酶活性显著升高(P＜0.05);血清TG、TC含量升高,SOD活性降低,血糖含量呈先升后降趋势.在投喂水平为6％时,小规格黄鳝的SOD和LZM活性均处在较高水平.本研究表明,当大规格黄鳝投喂水平为4.4％、小规格黄鳝投喂水平为5％-6％时,黄鳝的生长性能达到较佳状态.

Effects of Feeding Level on Growth, Intestinal Digestive Enzymes Activity and Physiological and Biochemical Characteristics of Serum in the Asian Swamp Eel (Monopterus albus)

An 8-week feeding experiment was conducted to study the effects of different feeding levels on growth performance,intestinal digestive enzyme activities and serum physiological and biochemical indices of Asian swamp eel (Monopterus albus) at two different sizes [mean initial body weight:big-size (68.85±0.44 g) and small-size (26.67±0.17 g)].There were four big-size groups which had 4 feeding rates (2.8％,3.6％,4.4％ and 3.6％ body weight/day);And five small-size groups which had 5 feeding rates (3.0％,4.0％,5.0％,6.0％ and 7.0％ body weight/day).The stocking densities were 50 fry/4500-1itre tank of big-size groups and 100 fry/4500-1itre tank of small-size groups.Each group had three biological repeats.The results showed that with the increase of feeding levels for the two sizes of swamp eel,the weight gain rate,feed coefficient,liver body rate,and content of fat in the whole fish were significantly higher (P＜0.05),but the content of protein in the whole fish had a decreasing tendency.When the feeding level was 4.4％ and 5.2％ for big-size swamp eel,the weight gain rate reached a peak,and there were no significant differences between the two groups.The activities of intestinal lipase and trypsin were significantly increased (P＜0.05) with the increase of feeding level;serum superoxide dismutase (SOD) activity and total cholesterol (TC) content showed a trend from rise to decline;serum triglycerides (TG) content was rising.When the feeding level was 4.4％,the activities of SOD and lysozyme (LZM) reached the highest level among all the groups of big-size swamp eel.In pace with the rising of feeding level for the small-size groups,intestinal trypsin activity was increased significantly (P＜0.05);the content of serum TG and TC rose gradually;the SOD activity was decreased;the content of blood sugar had a fluctuated trend.Compared with other groups of small-size swamp eel,the activities of SOD and LZM had higher standards when the feeding level was 6％.In conclusion,when the feeding level were 4.4％ for the big-size and 5％-6％ for the small-size respectively,the growth performance of swamp eel reached a better status.