左旋咪唑对罗氏沼虾免疫功能及抗病力的影响

以0(对照)、50、100和150 mg/kg饲料的剂量将左旋咪唑(LMS)添加于基础饲料中制成颗粒饲料投喂罗氏沼虾(Macrobrachium rosenbergii)14 d,采样测定了罗氏沼虾血细胞吞噬活性、血清酚氧化酶(PO)、溶菌酶(LSZ)及超氧化物岐化酶(SOD)活性,并以6×105cells/mL浓度的致病性嗜水气单胞菌(Aerom onas hydrophila)对罗氏沼虾进行肌肉注射(20μL/尾),记录接种7 d后罗氏沼虾的累积死亡率。结果表明,3个LMS处理组的罗氏沼虾血细胞吞噬百分比和吞噬指数、血清PO、LSZ及SOD活性均显著地高于对照组(P<0.05);LMS处理组的罗氏沼虾对嗜水气单胞菌的抵抗力明显增强。因此,饲喂适量的LMS能促进罗氏沼虾的免疫力和抗病力;在本试验条件下,100 mg/kg饲料的剂量为最适添加剂量。

Effects of Levamisole on the Immune Function and Disease Resistance of Macrobrachium rosenbergii

In order to determine the immunomodulatory effect of the dietary intake of levamisole in the giant freshwater prawn(Macrobrachium rosenbergii),the prawn were fed diets containing 0(control),50,100 and 150 mg/kg dry diet for 14 days.The phagocytic activity,phenoloxidase(PO)activity,lysozyme(LSZ)activity and superoxide dismutase(SOD)activity were examined at once after administration of levamisole.Prawn were challenged with a virulent strain of Aeromonas hydrophila of M.rosenbergii at a concentration of 6 × 105 cells /mL 20 μL/prawn)at once after administration of levamisole,and mortalities were recorded over a 7 d period.The results demonstrated that prawn treated with levamisole showed significantly higher phagocytic percentage(PP)and phagocytic index(PI)of haemocyte,the PO activity,LSZ activity and SOD activity than those of the control group(P<0.05).Furthermore,M.rosenbergii treated with levamisole had significantly stronger resistance to Aeromonas hydrophila.It was concluded that M.rosenbergii that were fed with diets at 50,100 or 150 mg/ kg dry diet showed increased immune ability as well as resistance to A.hydrophila infection.Under the experimental condition,the optimum dose of dietary intake of levamisole should be 100 mg levamisole/kg dry diet.