枯草芽孢杆菌微胶囊制剂对中华绒螯蟹免疫机能及抗病力的影响

Effects of Bacillus subtilis capsule on immune function and anti-disease ability of Chinese mitten crab

在基础饲料中分别添加0(对照)、1、5g/kg的枯草芽孢杆菌海藻酸钠微胶囊冻干粉(活菌含量为2.2×1011CFU/g),制成颗粒饲料后投喂中华绒螯蟹7d,然后将两个试验组改投喂对照组饲料。在停喂试验组饲料后第0、1、2、3周,分别测定中华绒螯蟹血细胞呼吸爆发活性、血清酚氧化酶(PO)、溶菌酶(LSZ)和酸性磷酸酶(ACP)活性,并在停喂试验组饲料后第2周,以1.2×107CFU/kg体重的剂量,体腔注射致病性嗜水气单胞菌CL99920菌株,记录接种10d后中华绒螯蟹的累计死亡率。结果显示:在停喂试验组饲料后0周,5g/kg组的血细胞呼吸爆发活性显著高于对照组和1g/kg组(P<0.05);在多数采样时间点,5g/kg组的血清PO和LSZ活性显著高于对照组(P<0.05);在一些采样时间点,1g/kg组的血清PO和LSZ活性也显著高于对照组(P<0.05);两个试验组的血清ACP活性与对照组无显著差异(P>0.05);试验组蟹对嗜水气单胞菌的抵抗力明显增强。本研究表明,饲喂5g/kg饲料剂量的枯草芽孢杆菌微胶囊制剂可增强中华绒螯蟹的免疫力和抗病力。

The purpose of this study was to determine the variance of immune function of Chinese mitten crab （Er/ocheir sinensis）after being fed with the diets added 0,1 g/kg and 5 g/kg dry diet lyophilized powder of alginate microcapsules of living Bacillus subtilis （2.2×10^11 CFU/g powder）for 7 days,respectively.Mter 7 days,two test were feel basal diet. The respiratory burst （release of superoxide anion） of haemocytes, phenoloxidase （PO）, lysozyme （LSZ） and acid phosphatase （ACP）activities in serum were examined on the 0, 1st,2nd and 3th weeks after last administration with the diets of test groups.Crab were challenged at 1.2×10^7 CFU/kg crab weight with a virulent strain of Aeromonas hydrophila（CL99920）of E.sinensis on the 2nd weeks after last administration with the diets of test groups,and mortalities were recorded over a 10- day period.The results indicated that the respiratory burst activities of haemocytes of 5 g/kg group were significantly higher than control group and 1 g/kg group on the 0 week after last administration with the diets of test groups （P 〈 0.05）.The PO and LSZ activities in serum of 5 g/kg group were significantly higher than that in control group at most of the sampling time points （P 〈 0.05）.The PO and LSZ activities in serum of 1 g/kg group were also significantly higher than control group at some sampling time points（P 〈 0.05）.No significant differences of the ACP activities between two test groups and the control group （P 〉 0.05） were observed.h was concluded that E.sinensis supplemented in diets at 5 g/kg dry diets showed strong immune ability as well as resistance to A.hydrophila infection.