The total microbial flora from meat immediately after slaughter is quite different from that which develops during subsequent storage. In the review by Ayres (1955) on the microbiological implications in the slaughtering of meat animals, the results of eight studies are presented. Of the 19 bacterial genera cited, those genera most often isolated from freshly slaughtered beef included Pseudomonas, Micro coccus, Streptococcus, Achromobacter, Flavobacterium, Escherichia and Bacillus. It is interesting to note that two genera which are often associated with meat spoilage, Lactobacillus and Clostridium, are among those isolated least often, being reported by only one and two authors, respectively, of the eight reviewed. Eighteen different genera of molds and yeasts were also cited as being re covered from meat. The microbial populations on fresh meat immediately after slaughter and in retail markets were investigated by Stringer e;t a^. (1969). They found that the flora of beef carcasses in the packing plant consisted of Pseudomonas, Micrococcus, Sarcina, Flavobacterium and Bacillus, with Pseudomonas and Micrococcus predominating. At the retail level, however, micrococci were absent and Pseudomonas and Achromobacter predominated. The muscles of various animals