Molecular detection of Blastocystis sp. subtype 14 in the Yezo sika deer (Cervus nippon yesoensis) in Hokkaido, Japan.

This study describes the first report of Blastocystis sp. colonization in the sika deer (Cervus nippon) in Japan and in other animals in Hokkaido, Japan. Blastocystis sp. is one of the most widespread intestinal protist in a wide range of animals. Blastocystis sp. isolated from mammalian and avian species have been classified into 17 subtypes (STs). Some of the STs are zoonotic. The aim of this study was to evaluate Blastocystis sp. colonization in the Yezo sika deer (Cervus nippon yesoensis) in Hokkaido, Japan. The Yezo sika deer are currently overabundant and they are expanding their habitat to humans and livestock. A total of 132 deer fecal samples were subjected for molecular detection of Blastocystis sp. Of these, 60 (45.5%) samples were positive using PCR, which targets the small subunit ribosomal RNA gene sequence. All Blastocystis sp. DNA sequences from the Yezo sika deer were genotyped into ST14, which were originally reported in cattle. These findings indicate that the current public health risks of Blastocystis sp. from the Yezo sika deer is low, although more detailed future analysis is required.

Development and evaluation of a novel loop-mediated isothermal amplification (LAMP) method targeting Theileria parasites infecting Yezo sika deer.

The increasing Yezo sika deer (Cervus nippon yesoensis) population is creating a large problem. Yezo sika deer are an important blood meal source, and these deer contribute to the maintenance of tick populations. Theileria spp. infections in Yezo sika deer and T. orientalis infections in cows occur at high frequencies, and the same tick species infests both deer and cows. Therefore, a specific detection method to identify deer Theileria spp. is important. In this study, we establish a novel molecular detection method for identifying Theileria spp. from deer and tick samples using loop-mediated isothermal amplification (LAMP). This method targets a metalloprotease/cell division cycle protein gene homologue. Our LAMP protocol was able to detect deer Theileria and did not show cross reactivity with other closely related protozoan parasites, including T. orientalis. The LAMP method showed sensitivity and specificity equivalent to those of nested PCR performed on the same field samples from deer and ticks. These results demonstrate the applicability of LAMP to field surveys in which the detection of deer Theileria spp. is required. In conclusion, due to its simplicity, specificity, and reliability, we suggest our LAMP protocol as an appropriate method for routine surveys to detect Yezo sika deer and ticks infected with deer Theileria spp. parasites. Additionally, this LAMP method offers great promise as a useful tool to distinguish Yezo sika deer Theileria from related Theileria parasites present in livestock.

Phylogenetic comparison of avian haemosporidian parasites from resident and migratory birds in northern Japan.

We analyzed blood samples of resident and migratory Japanese birds to evaluate the prevalence and genetic background of avian blood parasites in northern Japan. We used PCR targeting the mitochondrial cytochrome b gene to examine infections of Leucocytozoon, Haemoproteus, and Plasmodium parasites in blood samples from 243 birds of 14 species in three orders (Passeriformes, Columbiformes, and Anseriformes). Sequences were subjected to phylogenetic analysis. The infection rate was 21% in pigeons (Columbiformes) and 17% in Anseriformes. A high infection rate of 93.8% was found in crow species (Passeriformes). Haemoproteus and Plasmodium parasites were detected in only two species. Infected blood samples obtained from seven bird species involved two major clades of Leucocytozoon, which were divided between resident and migratory birds. The parasites, which are genetically distinct from parasites in Japanese resident birds, may have been introduced to Japan by migratory bird species.