养殖密度对克氏原螯虾幼虾生长、消化酶活力和生理生化指标的影响

以体质量(0.015±0.004)g克氏原螯虾幼虾为研究对象,研究了50、100、300、600、900尾/m25种养殖密度对克氏原螯虾幼虾生长、消化酶活力和生理生化指标的影响,实验周期为30 d。结果显示,克氏原螯虾幼虾的终末体质量随着养殖密度的增大而减小。胃蛋白酶、类胰蛋白酶和淀粉酶活力随着养殖密度的增大表现出减小趋势,纤维素酶和脂肪酶活力在5种养殖密度下变化规律不显著(P>0.05)。克氏原螯虾幼虾体内水分含量在5种养殖密度下差异较小(P>0.05);粗蛋白含量随养殖密度的升高呈增高趋势,由54.02%增高至60.75%(P<0.05);粗脂肪含量不断减少(P<0.05),由26.19%减少至19.19%(P<0.05)。随着养殖密度的增大,克氏原螯虾幼虾肌肉葡萄糖的含量呈下降趋势(P<0.05),甘油三酯、总蛋白、尿素氮和胆固醇含量呈不断增多趋势(P<0.05)。克氏原螯虾幼虾肝胰腺葡萄糖、甘油三酯、总蛋白和尿素氮含量随着养殖密度的增大呈不断增多趋势。结果表明,高密度养殖对克氏原螯虾幼虾生长和消化酶活力具有一定负面影响,体内蛋白、脂肪、葡萄糖和尿素氮等物质的含量也随着养殖密度的增大而发生变化。

Effects of stocking density on growth,digestive enzyme activities and biochemical indices of juvenile Procambarus clarkiiXIAO Ming-he, XIAO Ying-ping, WU Zhi-qiang, HU Xiang-ping

Stocking density is a crucial factor involved in aquatic productivity. This paper evaluates the effects of stocking density on growth, digestive enzyme activities and biochemical indices of juvenile Procambarus clarkii, whose initial average body weight was (0.015±0.004) g. A 30-day rearing experiment was conducted to investigate the effects of stocking density on growth, digestive enzyme activities and biochemical indices of juvenile Procambarus clarkii in this study. Its initial average weight was (0.015±0.004) g and the initial stocking density was at the stocking densities of 50, 100, 300, 600, and 900 individuals/ m² respectively. Results showed that the final body weight of juvenile P. clarkii decreased with the increasing stocking density. The activities of pepsin, tryptase, and amlase presented the reduced trend with the increasing stocking density, while cellulase and, lipase, and the content of moisture were indistinctively changed (P > 0.05). TThe content of moisture was insignificantly different (P > 0.05). The content of crude protein increased , from 54.02% to 60.75% (P < 0.05), and also, muscle concentrations of triglyceride, total protein, urea nitrogen, and cholesterol increased (P < 0.05) with the increasing stocking density, while the content of crude fat decreased, from 26.19% to 19.19% (P < 0.01) with the increasing stocking density. Muscle, and concentration of glucose in muscle in the same mannerdecreased, while triglyceride, total protein, urea nitrogen, and cholesterol increased (P < 0.05) with the increasing stocking density. Increasing trends of Hepatopancreas hepatopancreas concentrations of glucose, triglyceride, total protein, and urea nitrogen with the increasing stocking density were observedincreased. These data indicate that high stocking density exerts a negative impact on the growth and digestive enzymes of juvenile Procambarus clarkii, a. nd could alter theThe contents of protein, fat, glucose, and urea nitrogenare altered as stocking density increases.