Morphologic, host specificity, and molecular characterization of a Hungarian Cryptosporidium meleagridis isolate

This study was undertaken in order to characterize Cryptosporidium meleagri dis isolated from a turkey in Hungary and to compare the morphologies, host specificities, organ locations, and small subunit RNA (SSU rRNA) gene sequ ences of this organism and other Cryptosporidium species. The phenotypic di fferences between C. meleagridis and Cryptosporidium parvum Hungarian calf isolate (zoonotic genotype) oocysts were small, although they were statisti cally 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 varia ble region of the SSU rRNA gene of C. meleagridis isolated from turkeys wit h other Cryptosporidium sequence data in the GenBank database revealed that the Hungarian C. meleagridis sequence is identical to a C. meleagridis seq uence recently described for a North Carolina isolate. Thus, C. meleagridis is a distinct species that occurs world,vide and has a broad host range, l ike the C. parvum zoonotic strain (also called the calf or bovine strain) a nd Cryptosporidium felis. Because birds are susceptible to C. meleagridis a nd to some zoonotic strains of C. parvum, these animals may play an active role in contamination of surface waters not only with Cryptosporidium baile yi but also with C. parvum-like parasites.