Establishment of serological test to detect antibody against ferret coronavirus.

Since there is no available serological methods to detect antibodies to ferret coronavirus (FRCoV), an enzyme-linked immunosorbent assay (ELISA) using recombinant partial nucleocapsid (N) proteins of the ferret coronavirus (FRCoV) Yamaguchi-1 strain was developed to establish a serological method for detection of FRCoV infection. Many serum samples collected from ferrets recognized both a.a. 1-179 and a.a. 180-374 of the N protein, but two serum samples did not a.a. 180-374 of the N protein. This different reactivity was also confirmed by immunoblot analysis using the serum from the ferret.Therefore, the a.a. 1-179 of the N protein was used as an ELISA antigen. Serological test was carried out using sera or plasma of ferrets in Japan. Surprisingly, 89% ferrets in Japan had been infected with FRCoV. These results indicated that our established ELISA using a.a. 1-179 of the N protein is useful for detection of antibody to FRCoV for diagnosis and seroepidemiology of FRCoV infection.

Molecular characterization of Giardia duodenalis isolates from domestic ferrets.

Giardia duodenalis is a pathogen that has been found in a variety of mammals, including humans, and consists of host-specific (assemblages C, D, E, F, and G) and zoonotic (assemblages A, B) genetic groups. Ferrets are popular pets, and they, like humans, are hosts to this pathogen. The genetic characteristics of the Giardia population in ferrets are unclear because only one ferret isolate has been genotyped. To develop a more complete picture of the genetic characteristics of the Giardia population in domestic ferrets two additional Giardia isolates, recovered independently from two ferrets suffering from intestinal or hepatic giardiasis, were analyzed genetically. The sequences of both isolates at three loci, small subunit ribosomal RNA (SSUrDNA, 292 bp), beta-giardin (734 bp), and glutamate dehydrogenase (GDH, 713 bp) were identical to each other, but the sequences of triosephosphate isomerase locus (TPI, 512 bp) had five substitutions between isolates. Sequence homology and phylogenetic analyses at four loci identified both isolates as members of the assemblage A. Moreover, the sequences of SSUrDNA, beta-giardin, and GDH from both isolates were identical to those of the previous ferret isolate genotyped as assemblage A within the regions of overlap. The result obtained in the present study indicates that at least two genetically different types in assemblage A exist in domestic ferrets. In addition, there have been no reported human and animal isolates with the same sequence as those from ferret isolates at all four loci examined, suggesting that the present ferret isolates might be host-specific.

First record of Eimeria furonis infection in a ferret, Japan, with notes on the usefulness of partial small subunit ribosomal RNA gene sequencing analysis for discriminating among Eimeria species.

Eimeria is a genus of apicomplexan parasites found in a variety of vertebrates including the weasel. At present, three species have been reported in members of the weasel family, but the presence of weasel Eimeria in Japan have been quite unclear. The identification of Eimeria species has been performed based on oocyst morphology, host species, and habitat in the host, but sometimes discriminating among morphologically similar species under light microscopy is impossible. The present study detected for the first time the weasel coccidium, E. furonis, in a ferret in Japan. Since molecular information for E. furonis has been quite unclear, this species was compared molecularly with other Eimeria species, and also the usefulness of sequencing analysis of the small subunit ribosomal ribonucleic acid gene (SSUrDNA) for discriminating among Eimeria species was examined. About the 350-bp sequence of SSUrDNA of all species including E. furonis compared differed from each other, and its differences found in Eimeria species were also reflected in the phylogram constructed using the partial nucleotide sequences. The sequencing analysis of partial SSUrDNA examined in the present study thus appears useful for discriminating among morphologically similar Eimeria species.