The antimicrobial susceptibilities of 72 Brachyspira hyodysenteriae isolates collected from clinical cases of swine dysentery (SD) in 11 prefectures in Japan between 1985 and 2009 were investigated using an agar dilution method and 5 antimicrobial agents. Our results revealed a tendency of Japanese field isolates of B. hyodysenteriae to acquire resistance to the main antimicrobials used in SD treatment such as tiamulin, valnemulin, and efrotomycin. Therefore, a responsible approach for the selection and use of antimicrobial agents is required for SD treatment.
(Research Team for Environmental/Enzootic Diseases, Kyushu Research Station, TEL +81-29-838-7708)
