鸽源贝氏隐孢子虫对鸡的致病性及其防治药物的筛选

Study on pathogenicity and drug treatment for chicken infected with Cryptosporidium baileyi isolates from pigeon

用鸽源贝氏隐孢子虫广东分离株感染3日龄岭南黄鸡,通过感染动物所表现的临床症状、排卵囊情况和病理学变化特征,分析鸽源贝氏隐孢子虫在不同禽类宿主之间的适应性及致病性特点。选取8种中药复方制剂和西药代谢酶抑制剂对感染雏鸡进行初步药物治疗试验,以各组雏鸡发育状况、增重、采食量、卵囊排出情况以及组织病理学变化为观察指标,考察这8种药物对鸽源贝氏隐孢子虫的作用。结果显示,鸽源贝氏隐孢子虫对雏鸡感染的临床症状与其他禽源贝氏隐孢子虫相近,但鸽源贝氏隐孢子虫卵囊在雏鸡体内的潜隐期为5d,比已报道的鸡源贝氏隐孢子虫的潜隐期稍短,卵囊排出量出现多个高峰期,持续排卵囊时间为20d。药物筛选试验表明,中药复方(川楝子、槟榔、常山、石榴皮、地榆)3组在采食量、增重量、卵囊排出量以及寄生器官损伤程度上都有表现出一定效果,提示中药复方3可能对雏鸡贝氏隐孢子虫病有潜在防治作用。

To study the adaptability and pathogenicity of Cryptosporidium baileyi oocysts between different avian hosts,and to screen the effective drug treatment,3days-old Lingnan yellow broilers were inoculated with C.baileyi oocysts which was isolated from pigeons in Guangdong Province.After infection,the clinical symptom,oocyst shedding as well as histopathology characteristics from the animals were studied.In addition,the effect of anti-cryptosporidial from eight kinds of traditional Chinese medicines and western drugs were tested based on the evaluation of main clinical symptoms,weight gains,pattern of shedding oocysts,and histopathology changes of the infected chickens.The results have shown that C.baileyi from pigeons and other avian origins shared similar clinical symptoms,but the pigeon isolate had shorter latent period than chicken origins.Results from drug screening test indicated that the traditional Chinese medicines has superior effect than the western medicines.Especially,the Chinese medicine group 3showed optimal performance on the aspect of weight gain,oocysts discharge and the reduction damage of parasitic organ,which indicated that this medicine is a potential candidate for prevention and treatment of cryptosporidiosis.