壳寡糖对红鳍东方鲀血液指标和非特异性免疫指标的影响

Effects of dietary chitosan on hematological parameters and non-specific immunity of redfin puffer Takifugu rubripes

为研究壳寡糖(chitosan-oligosaccbarides,COS)对红鳍东方鲀Takifugu rubripes血清和血液生化指标及非特异性免疫指标的影响,选用体质量为(129.2±3.1)g的红鳍东方鲀600尾,随机分为C0、C1、C2、C3 4组,每组设3个平行,在基础饲料中分别添加0、500、1000、2000 mg/kg的壳寡糖,经56 d饲养后,测定其血液指标、抗氧化酶活性及其攻毒耐受性。结果表明:饲料中添加壳寡糖能显著提高血清中碱性磷酸酶、溶菌酶、过氧化氢酶、超氧化物歧化酶活力和全血中血小板数量(P<0.05),各项指标随壳寡糖添加量的增加整体呈升高趋势;饲料中添加壳寡糖能显著提高红鳍东方鲀肝脏组织中过氧化氢酶、超氧化物歧化酶活力(P<0.05),显著降低丙二醛含量(P<0.05);壳寡糖能明显提高红鳍东方鲀对迟缓爱德华氏菌和哈维弧菌的抵抗力。研究表明,在本试验条件下,饲料中添加2000 mg/kg壳寡糖能够提高红鳍东方鲀的非特异性免疫功能。

Juvenile redfin puffer Takifugu rubripes with body weight of （ 129.2＋3.1 ） g were reared in a plastic 2 m3 tank at a density of 50 fish per treatment and fed a basal diet supplemented with chitosan-oligosaccharides at dose of 0（ CO）, 500（ C1 ）, 1000（C2） and 2000（ C3 ） mg/kg for 56 days at water temperature of （17.0±2.0）℃ with triplication to evaluate the effects of chito-oligosaccharides on serum, blood biochemical parameters and non-specif- ic immunity function of redfin puffer. The results showed that there were significantly higher contents of blood plate- let and higher activities of serum alkaline phosphatase, lysozyme, catalase, and superoxide dismutase in the fish fed the diets supplemented with chitosan-oligosaccharides than those in the fish fed the control diet（ P〈0.05 ）, in- crease with elevated close of chitosan-oligosaccharides. The redfin puffer juveniles fed the diets containing chitosan- oligosaccharides had significantly higher activities of hepatic catalase, and superoxide dismutase and significantly lower malondialdehyde content in liver than the fish fed the control diet（ P〈0.05 ）. The redfin puffer juveniles fed the diets containing chitosan-oligosaccharides showed high resistance to Edwardsiella tarda and Vibrio harvey. It can be concluded that dietary supplementation of chito-oligosaccharides can improve the non-specific immunity function of redfin puffer, and that the supplemental level of chitosan-oligosaccharides in diets is suggested to be 2000 mg/kg diet.