贵阳动物园动物隐孢子虫的调查与虫种鉴定

Investigation and identification of Cryptosporidium from animals in Guiyang Zoo

为了解贵阳动物园圈养野生动物隐孢子虫的感染流行情况,以骆驼、黑熊、斑马、袋鼠、猕猴、长臂猿、大象等野生动物的新鲜粪便为样品(n=84),采用饱和蔗糖溶液漂浮法收集隐孢子虫的卵囊并提取D N A,以18S r R NA为目标基因靶点设计特异性引物,并采用巢式PCR扩增目的基因,后经10 g/L琼脂糖凝胶电泳,对检测结果为阳性的PCR产物进行序列分析并建立系统发育树。结果表明,共有13份隐孢子虫阳性样品,其中骆驼7份,感染率为70.00%,感染虫种为安氏隐孢子虫;斑马1份,感染率为10.00%,感染虫种为安氏隐孢子虫;长臂猿5份,感染率为23.81%,感染虫种为微小隐孢子虫、人隐孢子虫及小鼠隐孢子虫。本次调查发现该园野生动物隐孢子虫具有较高的总体感染率(15.50%)和鉴定出4种人兽共患隐孢子虫虫种,具有较重要的公共卫生意义。本研究首次报道了我国斑马感染隐孢子虫。

In order to figure out the occurrence of Cryptosporidium in captive wild animals kept in Guiyang Zoo of Guizhou Province, we examined 84 fecal samples from camels, black bears, zebras, kangaroos, rhesus monkeys, gibbons and elephants. Sheather＇s sucrose flotation technique was used to collect oocysts and primers were designed for nested PCR amplification of 18 S r RNA of Cryptosporidium. Finally, PCR products were examined by 10 g/L agarose gel electrophoresis and the positive products were sequenced and a phylogenetic tree was constructed. In result, there were 13 positive samples for Cryptosporidium. Seven camels were infected with C. andersoni and the infection rate was 70%. A zebra was infected with C. andersoni with the infection rate of 10%. Five gibbons feces with an infection rate of23.81% were Cryptosporidium-positive, and C. parvum, C. hominis and C. muris were identified.The relatively high prevalence（15.5%） and the occurrence of four zoonotic Cryptosporidium species have a public significance. This is the first report of zebras infected with Cryptosporidium in China.