Occurrence of bovine dermatophilosis in the southernmost islands of Japan.

Such cutaneous symptoms as characteristic incrustation and alopecia were noticed in 25 calves of the indigenous Japanese Black breed grazing on subtropical islands in Japan over a period of April, 1978 to February, 1980. These islands were Ishigaki, Kuro, Yonaguni and Tarama belonging to the Sakishima Islands. Microbiological and pathological examination on three of these calves revealed that the calves were affected with dermatophilosis caused by Dermatophilus congolensis. The disease in these calves seemed to be the same as that reported previously in other countries, since it attacked young calves in a humid district with an abundant rainfall. It broke out first on Ishigaki Island and subsequently on the other islands in 3 years. Discussion was made on factors inducing these outbreaks.