RESUMO
The number of wild sika deer (Cervus nippon yesoensis) continues to increase in Hokkaido Prefecture, Japan. The major concern for the livestock industry is the transmission of pathogens between sika deer and cattle. Fasciolosis is an important disease that can occur in both animals. The aim of this study was to examine the possible mutual transmission of this disease in Hokkaido Prefecture. A total of 105 Fasciola flukes were obtained from sika deer and 96 from domestic cattle. The Fasciola flukes in Japan are reported to possess no mature sperm. However, in this study, 14 flukes from sika deer and eight flukes from cattle contained mature sperm in their seminal vesicles. All the Fasciola flukes from the two host animals had Fh/Fg type in nuclear phosphoenolpyruvate carboxykinase (pepck) gene, with a mixed fragment pattern derived from F. hepatica and F. gigantica, which are considered to be hybrid Fasciola flukes. However, almost all the flukes had Fsp1 haplotype in NADH dehydrogenase subunit 1 (nad1) gene, indicating that their maternal lineage was F. hepatica. A new haplotype, Fsp3, was detected in one fluke obtained from cattle and differed in one nucleotide from Fsp1. Therefore, the Fasciola flukes detected in both host species had almost identical molecular characteristics. These findings suggest the mutual transmission of Fasciola flukes between sika deer and domestic cattle in Hokkaido.
Assuntos
Doenças dos Bovinos/parasitologia , DNA de Helmintos/genética , Cervos/parasitologia , Fasciola/genética , Fasciolíase/veterinária , Animais , Bovinos , DNA Mitocondrial/genética , Fasciola/isolamento & purificação , Fasciola/patogenicidade , Fasciolíase/epidemiologia , Fasciolíase/parasitologia , Fasciolíase/transmissão , Haplótipos , Japão/epidemiologia , Gado/parasitologia , NADH Desidrogenase/genética , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Análise de Sequência de DNARESUMO
Adult schistosomes were detected in the veins or capillaries of the large intestine, mesentery, liver, and adrenal glands in eight of 13 whooper swans (Cygnus cygnus) examined in Iwate Prefecture, Japan. However, neither eggs nor severe tissue injuries were observed in any of the swans. The schistosomes were definitively identified as Allobilharzia visceralis based on the nucleotide sequences of the ribosomal internal transcribed spacer (ITS) region. Allobilharzia visceralis infections have been reported in whooper swan in Iceland and tundra swan (Cygnus columbianus) in North America. These detections suggest that A. visceralis is distributed extensively along the swan flyways because the swans are migratory birds. To the best of our knowledge, this is the first report of A. visceralis infection in Asia.