Variation in Morphological and Biochemical Characteristics of Anaerobic Butyric Acid Bacteria

Abstract

IN attempts to identify the butyric acid bacilli not liquefying gelatin present in silage-fodder, cow fæces, milk and cheese, we generally found it very difficult or even impossible to determine the exact species of the organisms isolated. In most cases our freshly isolated pure cultures differed, in morphological and biochemical properties, from the species described in literature. Furthermore, one and the same strain, when repeatedly examined, frequently showed great variations with time ; a certain strain, which behaved as a representative of the species a at one time, later showed the characteristics of the species b.