Sréter T, Kovács G, da Silva A J, Pieniazek N J, Széll Z, Dobos-Kovács M, Márialigeti K, Varga I
Departments of Parasitology and Pathology, Szent István University Faculty of Veterinary Science, Hungary.
Appl Environ Microbiol. 2000 Feb;66(2):735-8. doi: 10.1128/AEM.66.2.735-738.2000.
This study was undertaken in order to characterize Cryptosporidium meleagridis isolated from a turkey in Hungary and to compare the morphologies, host specificities, organ locations, and small-subunit RNA (SSU rRNA) gene sequences of this organism and other Cryptosporidium species. The phenotypic differences between C. meleagridis and Cryptosporidium parvum Hungarian calf isolate (zoonotic genotype) oocysts were small, although they were statistically significant. Oocysts of C. meleagridis were successfully passaged in turkeys and were transmitted from turkeys to immunosuppressed mice and from mice to chickens. The location of C. meleagridis was the small intestine, like the location of C. parvum. A comparison of sequence data for the variable region of the SSU rRNA gene of C. meleagridis isolated from turkeys with other Cryptosporidium sequence data in the GenBank database revealed that the Hungarian C. meleagridis sequence is identical to a C. meleagridis sequence recently described for a North Carolina isolate. Thus, C. meleagridis is a distinct species that occurs worldwide and has a broad host range, like the C. parvum zoonotic strain (also called the calf or bovine strain) and Cryptosporidium felis. Because birds are susceptible to C. meleagridis and to some zoonotic strains of C. parvum, these animals may play an active role in contamination of surface waters not only with Cryptosporidium baileyi but also with C. parvum-like parasites.
本研究旨在对从匈牙利一只火鸡中分离出的火鸡隐孢子虫进行特征描述，并比较该生物体与其他隐孢子虫物种的形态、宿主特异性、器官定位以及小亚基RNA（SSU rRNA）基因序列。火鸡隐孢子虫与微小隐孢子虫匈牙利小牛分离株（人畜共患基因型）卵囊之间的表型差异虽小，但具有统计学意义。火鸡隐孢子虫的卵囊在火鸡中成功传代，并从火鸡传播至免疫抑制小鼠，再从小鼠传播至鸡。火鸡隐孢子虫的定位与微小隐孢子虫一样，都在小肠。将从火鸡中分离出的火鸡隐孢子虫SSU rRNA基因可变区的序列数据与GenBank数据库中其他隐孢子虫序列数据进行比较，结果显示匈牙利火鸡隐孢子虫序列与最近描述的北卡罗来纳州分离株的火鸡隐孢子虫序列相同。因此，火鸡隐孢子虫是一个独特的物种，在全球范围内都有出现，并且具有广泛的宿主范围，就像微小隐孢子虫人畜共患菌株（也称为小牛或牛菌株）和猫隐孢子虫一样。由于鸟类易感染火鸡隐孢子虫和某些人畜共患的微小隐孢子虫菌株，这些动物可能不仅在贝利隐孢子虫污染地表水方面，而且在类似微小隐孢子虫的寄生虫污染地表水方面都发挥着积极作用。
