Diagnosis of Bacillus larvae --the causative agent of American foulbrood]

The authoress studied the growth of Bacillus larvae on different nutrient media and its ability of decomposing hydrogen peroxide and reducing nitrates. There are also instructions for rapid cultivation and biochemical diagnosis of Bacillus larvae. It can be performed in any microbiological laboratory, the culture medium can be prepared from available commercially produced preparations, and B. larvae can be detected in suspected material even out of the season, if the method of selective cultivation and repeated pasteurizing is used. Catalase test is proposed to be added to the examination; the result of this test was negative in all 96 strains studied. Photographic documentation of different developmental stages of B. larvae can serve as an aid in microbiological examination.