摘要
研究了循环水养殖模式下,不同养殖密度对青石斑鱼Epinephelus awoara生长及肝脏、鳃相关酶活性和血液指标的影响。试验设10、20、30 kg/m33个养殖密度组,每组设3个重复,在闭合循环水养殖系统(70 cm×40 cm×40 cm)中养殖初始体质量为(108.7±4)g的青石斑鱼50 d。结果表明:1)10、20 kg/m3养殖密度组青石斑鱼的增重率、特定生长率均高于30 kg/m3密度组(P<0.05),但30 kg/m3密度组鱼的饲料系数高于其他两组(P<0.05);2)各组试验鱼血清的谷丙转氨酶(GPT)、谷草转氨酶(GOT)活性及肝脏和鳃的GPT活性均随着养殖密度的增加而明显升高,且组间有极显著性差异(P<0.01);3)各组试验鱼血清中的皮质醇含量随着养殖密度的增加而明显升高(P<0.01),而红细胞数则明显减少(P<0.01),30 kg/m3密度组鱼的血红蛋白含量低于10、20 kg/m3密度组(P<0.05);4)各组鱼的肌肉营养组成均无显著性差异(P>0.05)。本试验结果表明,养殖密度过高对青石斑鱼生长不利,但从经济收益角度考虑,适宜的养殖密度应为20 kg/m3。
The grouper Epinephelus awoarea with an initial body weight of （ 108.7 ＋4） g were reared in a recirculat- ing system at stocking rate of 10,20 ,or 30 kg/m3 for 50 days with triplication to evaluate the effects of stocking den- sity on growth, enzyme activity in liver and gill, and blood physiological indices. The results showed that ： 1 ） There were significantly lower weight gain（WG） and specific growth rate （SGR） at a stocking density of 30 kg/m3 than at 10 kg/m3 and 20 kg/m3（p〈0.05 ）, with the maximal food conversion ratio at stocking density of 30 kg/ms. 2） The glutamatc-oxaloacetate transaminase （GOT） and glutamate-pyruvate transaminase （GPT） activities in the ser- um and the GPT activities in the liver and gill were found to be increased with the stocking density, with signifi- cantly different between the two groups （P〈0.01）. 3 ） There was an increase in the plasma cortisol level as the culture density was increased （P〈0.01）, while the count of red blood cells was found to be decrease（P〈0.01）. There was significantly lower hemoglobin level in 30 kg/m3 group than that in other two groups （P〈0.05）. 4） There was no significant difference in muscle nutrition compositions among three groups （P〉0.05）. Conclusively, over high density is unfavorable to the growth of the grouper, and 20 kg/m3 is considered as optimum stocking den- sity in terms of the economical profits.
出处
《大连海洋大学学报》
CAS
CSCD
北大核心
2012年第6期518-522,共5页
Journal of Dalian Ocean University
基金
农业科技成果转化资金资助项目(2012GB2B000086)
辽宁省教育厅创新团队项目(2009T018)
关键词
青石斑鱼
循环水养殖系统
养殖密度
生理指标
Epinephelus awoara
recirculating aquaculture system
stocking density
physiological index
