Prevalence and diversity of Hepatozoon canis in naturally infected dogs in Japanese islands and peninsulas

• Published in: Parasitology research (1987) 2013-09, Vol.112 (9), p.3267-3274
• Main Authors: El-Dakhly, Khaled Mohamed, Goto, Minami, Noishiki, Kaori, El-Nahass, El-Shaymaa, Hirata, Akihiro, Sakai, Hiroki, Takashima, Yasuhiro, El-Morsey, Ahmed, Yanai, Tokuma
• Format: Article
• Language: English
• Subjects: Amblyomma; Animals; Biological diversity; Biomedical and Life Sciences; Biomedicine; blood; Canis; Coccidiosis - epidemiology; Coccidiosis - parasitology; Coccidiosis - veterinary; DNA Primers - genetics; DNA, Protozoan - genetics; DNA, Ribosomal - genetics; Dog Diseases - epidemiology; Dog Diseases - parasitology; Dogs; Eucoccidiida - genetics; Eucoccidiida - isolation & purification; Female; females; gametocytes; genes; Health aspects; Hepatozoon americanum; Hepatozoon canis; Host-parasite relationships; Immunology; Islands; Ixodidae; Japan - epidemiology; Male; males; Medical Microbiology; Microbiology; microscopy; Original Paper; Parasitemia - veterinary; Physiological aspects; polymerase chain reaction; Polymerase Chain Reaction - veterinary; Prevalence; Prevalence studies (Epidemiology); prospective studies; Rhipicephalus; ribosomal RNA; RNA, Ribosomal, 18S - genetics; Sporozoa; ticks
• ISSN: 0932-0113; 1432-1955
• DOI: 10.1007/s00436-013-3505-1

Canine hepatozoonosis is a worldwide protozoal disease caused by Hepatozoon canis and Hepatozoon americanum and is transmitted by ixodid ticks, Rhipicephalus and Amblyomma spp., respectively. H. canis infection is widespread in Africa, Europe, South America, and Asia, including Japan. The objective of this study was to study the distribution pattern and diversity of H. canis in naturally infected dogs in nine Japanese islands and peninsulas. Therefore, 196 hunting dogs were randomly sampled during the period from March to September 2011 and the ages and sexes were identified. Direct microscopy using Giemsa-stained blood smears revealed H. canis gametocytes in the peripheral blood of 45 (23.6 %) dogs. Polymerase chain reaction (PCR) was performed on EDTA-anticoagulated blood, initially with the common primer set (B18S-F and B18S-R) amplifying the 1,665-bp portion of the 18S rRNA gene, and then with the specific primer set (HepF and HepR) amplifying about 660 bp fragments of the same gene. Based on PCR, 84 (42.9 %) dogs were positive using the common primer and 81 (41.3 %) were positive using the specific primer. The current investigation indicated that all screened areas, except for Sado Island and Atsumi Peninsula, were infected. Yaku Island had the highest infection rate (84.6 % in males and 100.0 % in females), while Ishigaki Island showed the lowest infection rates (8.3 % in males and 17.7 % in females). Both sexes were infected with no significant difference. However, diversity of infection among the surveyed islands and peninsulas was significantly different (P