酵母细胞壁多糖对柔嫩艾美耳球虫感染雏鸡血清抗氧化能力的影响

Effect of yeast cell wall polysaccharides on antioxidant capacity in serum of chickens infected by Eimeria tenella

【目的】旨在评价酵母细胞壁多糖对柔嫩艾美耳球虫感染雏鸡血清抗氧化能力的影响。【方法】选取1日龄健康雏鸡180只,随机分为阴性对照组(雏鸡基础日粮+不攻虫)、阳性对照组(雏鸡基础日粮+攻虫)、酵母细胞壁多糖低剂量组(雏鸡基础日粮+酵母细胞壁多糖500mg/kg+攻虫)、酵母细胞壁多糖中剂量组(雏鸡基础日粮+酵母细胞壁多糖750mg/kg+攻虫)和酵母细胞壁多糖高剂量组(雏鸡基础日粮+酵母细胞壁多糖1 000mg/kg+攻虫)。14日龄时,除阴性对照组外其余各组雏鸡经口感染5 000个柔嫩艾美耳球虫孢子化卵囊。分别于21日龄和28日龄时,心脏采血后分离血清,采用酶联免疫吸附法检测过氧化氢酶活性、总超氧化物歧化酶活性、谷胱甘肽过氧化物酶活性和丙二醛的含量。于28日龄时摘取各组盲肠并石蜡包埋,切片后HE染色,在显微镜下观察盲肠的病理变化。【结果】与阳性对照组相比,酵母细胞壁多糖可以缓解柔嫩艾美耳球虫引起的盲肠病变,还可以显著提高同日龄柔嫩艾美耳球虫感染雏鸡血清中的谷胱甘肽过氧化物酶活性、过氧化氢酶活性和超氧化物歧化酶活性(P<0.05)且呈现一定正相关;显著降低其血清中丙二醛含量(P<0.05),且呈现一定负相关。【结论】酵母细胞壁多糖可通过提高感染柔嫩艾美耳球虫雏鸡的抗氧化能力而减轻柔嫩艾美耳球虫对雏鸡肠道损伤,以基础日粮中1 000mg/kg酵母细胞壁多糖为最适添加剂量。

[Objective]Searching the effect of yeast cell wall polysaccharides added to the feed ration on the serum antioxidant capacity of chickens infected by Eimeria tenella.[Methods]Healthy chickens of 1 day old were randomly divided into 5 groups,negative control group(feed ration),positive control group(feed ration),YPS low-dose group (feed ration+YPS 500 mg/kg),YPS medium-dose group(feed ration+YPS 750 mg/kg)and YPS high-dose group(feed ration+YPS 1000mg/kg).At 14 days old,all chickens were orally infected by 5000 Eimeria tenella sporulated oocysts except negative control group.Blood of each groups’chickens were collected at 21 and 28 days old,respectively,then serums were separated for antioxidant enzymes(CAT,T-SOD,GSH-Px)and lipid metabolites(MDA)assays by ELISA.Cecums of each groups were collected at 28 days of age and embedded into paraffin blocks.After paraffin sectioning and HE staining,the pathological changes of the cecum were observed by the microscope.[Results]Comparing with the performance of positive control group at the same age,yeast cell wall polysaccharides alleviated cecum lesions caused by Eimeria tenella and also significantly increased activities of glutathione peroxidase,catalase and superoxide dismutase in the serum of chickens infected by Eimeria tenella (P<0.05)and showed a positive correlation;it also significantly decreased malondialdehyde content in the serum of chickens infected by Eimeria tenella (P<0.05)and showed a negative correlation.[Conclusions]Yeast cell wall polysaccharides added to the ration can improve the antioxidant capacity in serum of chickens infected by Eimeria tenella.In comparison,the appropriate dose of yeast cell wall polysaccharides added to the ration is 1000 mg/kg.