Sterilizing effects of ethylene oxide gas on Ascosphaera apis

Abstract

Used MS 7911 of Ascosphaera apis was isolated from white mummified larvae of honeybees at the Gifu Livestock Hygiene Service Center in 1979. Ethylene oxide (EO) gas was tested on it. A. apis was cultivated on M4OY agar at 25°C for 7 days. Then, ascospores were harvested and sprayed upon combs, which were tested with EO gas. As a result 2% and 3% EO gas were effective at 20°C for both 24 and 6 hr. Besides, 0.5% and 1% EO gas were effective at 30°C for both 24 and 6 hr. and 5% and 7% EO gas at 30°C for both 2 and 1 hr.