枯草芽孢杆菌对水质及凡纳滨对虾幼体免疫指标影响的研究

研究了不同浓度的枯草芽孢杆菌（Bacillus substilis）对养殖环境水质和凡纳滨对虾（Penaeus vannamei）幼体抗病力相关酶活性的影响。结果表明，枯草芽孢杆菌能显著（P〈0．05）降低化学需氧量（COD）和氨氮（NH3-N）含量，抑制亚硝酸氮（NO2-N）的产生；当枯草芽孢杆菌投放浓度为1．25×10^4cfu·mL^-1时，水体中COD、NH3-N和NO2-N含量均值比对照组分别降低了65．30％、59．70％和88．64％；20d后测定对虾的碱性磷酸酶（AKP）、过氧化物酶（POD）、酚氧化酶（PO）、超氧化物歧化酶（SOD）、抗菌和溶菌活力，各值相对于对照组分别提高了3．67、1．64、0．45、3．06、2．57和1．14倍；成活率比对照组提高了10％，增重率是对照组的2．44倍。因此，一定浓度的枯草芽孢杆菌能改善凡纳滨对虾幼体的养殖水质进而提高凡纳滨对虾幼体的抗病力。

Effects of Bacillus substilis on water quality and immunization indicators of larval Penaeus vannamei

The effects of different densities of Bacillus substilis on water quality and on the immunity indicators of larval Penaeus vannamei were studied. The results demonstrated that B. substilis could significantly （P 〈 0.05） decrease the contents of COD, NH3-N and inhibit the production of NO2-N. With a density of 1.25 × 104cfu·mL-Xof B. substilis, the average contents of COD, NH3-N and NO2-N of the treated groups decreased 65.30%, 59.70% and 88.64% , respectively. After 20-day cultivation, alkaline phosphatase （AKP）, peroxidase （POD）, phenoloxidase （PO）, superoxide dismutase （SOD）, the activity of anti-bacterial enzyme and bacteriolysis of Penaeus vannamei increased 3.67, 1.64, 0. 45, 3.06, 2.57 and 1.14 times, respectively. Moreover, the survival rate of the treatment groups increased 10% and the weight gain increased 2. 44 times when compared with the control group. Therefore, it showed that appropriate density of B. substilis could improve the water quality and the anti-disease ability of P. vannamei.