Study on Blood Parasite Infection in the Japanese Rock Ptarmigan (Lagopus mutus japonicus) and Conservation Medicine for the Species

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We investigated Leucocytozoon infection in the Japanese rock ptarmigan (Lagopus mutus japonicus) ; this bird is one of the special natural monuments of Japan that inhabits the Japanese alpine regions. We examined blood samples from birds captured in the Kubiki, Hida, and Akaishi mountain ranges. Seventy-three blood samples from 42 males, 19 females, and 12 birds of unknown sex were used for this study. The rate of infection with Leucocytozoon was 78.1% in the 73 birds examined. This species was identified as L.lovati morphologically. We demonstrated that the L.lovati infection was distributed across wide ranges of ptarmigan populations from the northern to the southern alpine zones. There was no sex bias in the prevalence ratio. The prevalence of L.lovati and the level of parasitization of the blood cells tended to increase from spring through summer ; in contrast, a decrease was observed from summer through autumn. Although L.lovati infection was observed in a number of local populati … More ons inhabiting three mountainous regions, no infected birds were found in Mt.Johnen-dake and Mt.Maejohnen-dake. It is necessary to continue surveying the relationship between the population dynamics of the ptarmigan and the density of the arthropod vector from the perspective of in situ conservation of this endangered species. Furthermore, we conducted the molecular biological study on L.lovati from the rock ptarmigan with the hematozoa from eight species of Japanese birds for comparison. We used PCR and sequence analysis of the mitochondrial cytochrome b gene (cyt b) to compare the genetic background among these detected protozoa species. In 20 individuals of 22 samples, a single amplified band was detected from 6 of 8 bird species; 9 Japanese rock ptarmigans, 4 large-billed crows (Corvus macrorhynchos), 2 carrion crows (C.corone), 2 scops owls (Otus scops), 1 Japanese grosbeak (Eophona personate), and 2 brown-eared bulbuls (Hypsipetes amaurotis), respectively. Phylogenetic analysis based on the partial cyt b sequences revealed that all Leucocytozoon isolates in Japan closely grouped with other Leucocytozoon species previously reported in the literature. Among the Japanese isolates, the phylogenetic tree suggested that L.lovati from the Japanese rock ptarmigan may be basal to the parasites found in other bird species. Our study is the first to identify the molecular relationships among Leucocytozoon parasites in the avifauna of Japan. The vector of L.lovzti was also examined. More than 6 species of black-fly (Simuliidae) were observed around the habitats of the ptarmigan. The partial cyt b gene of Leucocytozoon detected from 7 of 150 black-flies captured in the Japanese alpine zone was completely same with L.lovati from the ptarmigans. This suggests the black-fly is one of the vectors of L.loved in the Japanese rock ptarmigan. Less