雏鸡感染堆型艾美耳球虫及体内一氧化氮的生成

摘要

The objective of this experiment was to gather evidence for production of nitric oxide (NO) during a primary infection with the protozoan parasite,Eimeria acervulina,which carries out its life cycle in the duodenum of broilers.The plasma nitrite (NO－2) level,the stable metabolites of NO,were determined by Griess reaction.Relationship between plasma levels of NO－2 and infective doses,and relationship between plasma levels of NO－2 and times after infection were examined.One-day-old Huangyu broilers were fed on starter feed for two weeks,and then divided into 6 groups(13 broilers for each group)according to the infective dose of oocysts,i.e.,0,1.1×103,3.0×103,9.0×103,2.7×104 or 8.1×104 oocysts per broiler for infective groups,to study the relationship between plasma levels of NO－2 and the infective doses.20 broilers were infected at the dose of 2.7×104 oocysts per broiler to study the relationship between plasma levels of NO－2 and times after E.acervulina infection.The experimental results showed that the plasma levels of NO－2 of broilers in all infective groups were higher than those in control one.With the increasing infective doses from 1.0×103 to 2.7×104 oocysts per broiler,the plasma levels of NO－2 were increased in a stepwise manner.When broilers were infected at the dose of 2.7×104 oocysts per broiler,the plasma level of NO－2 of broilers was significantly increased after experimental infection,and reached the peak top at the end of 4thd after infection.The time when the clinical signs,also the gross and histologic lesions of mucosal membrane in broiler's duodenum were most serious and lots of E.acervulina in different stages could be seen in slics. The results above-mentioned gave strong evidences that there is a good relationship between NO and Eimeria acervulina infection in broilers.%本研究利用Griess反应监测了雏鸡感染堆型艾美耳球虫(Eimeria acervulina)后血浆NO－2水平与球虫卵囊感染剂量之间的剂量-效应关系以及与感染时间之间的时间-效应关系。在剂量-效应关系试验中，以1.0×103～2.7×104个卵囊/只鸡的剂量给雏鸡感染E.acervulina后，其血浆NO－2水平随着感染剂量的增加而升高。在时间-效应关系试验中，以2.7×104个卵囊/只鸡的剂量感染雏鸡后，其血浆NO－2水平逐步升高，至感染后第4天末达到最高值。本试验结果表明，雏鸡血浆NO－2水平的达峰时间与临床所观察到的球虫发病最严重的时间以及肠道肉眼病变和显微病变最严重的时间相符。