Ixodid tick species recovered from domestic dogs in Japan.

The species of ixodid ticks (Acari: Ixodidae) recovered from domestic dogs in Japan between September to November 2000 and April to June 2001 were identified. A total of 4122 ticks, including 1624 larvae, 1200 nymphs, 1016 females and 282 males were removed from 1221 dogs during these periods. Haemaphysalis longicornis (Neumann) was the most frequently found (40.3% of dogs), followed by H. flava (Neumann) (16.1% of dogs), Rhipicephalus sanguineus (Latreille) (4.8% of dogs) and Ixodes ovatus (Neumann) (4.1% of dogs). Small numbers of H. hystricis (Supino), H. campanulata (Warburton), H. japonica (Warburton), H. ias (Nakamura and Yajima), I. persulcatus (Schulze), I. nipponensis (Kitaoka and Saito) and Amblyomma testudinarium (Koch) were also recovered. In the spring sample, a total of 1408 ticks (78 larvae, 411 nymphs, 792 adult females and 127 adult males) were recovered from 570 dogs. The autumn sample included a larger proportion of larval stage and fewer adult ticks (1546 larvae, 789 nymphs, 224 adult females and 155 adult males). Haemaphysalis longicornis, H. flava and I. ovatus showed a wide geographical distribution from northern to southern Japan, whereas R. sanguineus were mainly distributed in the subtropical Okinawa prefecture with a few exceptions. Dogs in rural areas more frequently carried H. longicornis, H. flava and I. ovatus than dogs in urban or suburban areas, whereas R. sanguineus was more associated with the dogs in urban/suburban areas. Exposure to a garden was significantly associated with R. sanguineus and exposure to woodland was significantly associated with H. flava and I. ovatus. This is the first systematic survey of canine ticks in Japan.