Bacillus thuringiensis associated with faeces of the Kerama-jika,Cervus nippon keramae,a wild deer indigenous to the Ryukyus,Japan

Faeces of the Kerama-jika (Cervus nippon keramae), a wild shika deer indigenous to the Ryukyus, Japan, were examined for the natural occurrence of Bacillus thuringiensis. Of the ten faecal samples tested, seven contained this organism. The frequency of B. thuringiensis was 8.5% among 387 colonies of spore-forming bacteria belonging to the Bacillus cereus/B. thuringiensis group. Of 33 B. thuringiensis isolates recovered, only one isolate, assigned to the serotype H3abc (serovar kurstaki), exhibited dual toxicity against larvae of the silkworm, Bombyx mori, and the mosquito, Aedes aegypti. All of 32 other isolates were serologically untypable or untestable, and were non-toxic to larvae of the two insect species.