On the Characters, Especially Pathogenicity of Micrococcaceae Isolated from Milk

1) Of 2132 udders of 538 milking cows 58 and 117 udders, respectively, were those which have clinical abnormalities and those which secret abnormal milk, and from 32 and 78 udders of eacn group Micrococcacere of 41 and 102 strains each were isolated and from 117 of 155 normal udders Micrococcaceae of 137 strains were isolated. 2) Of total 280 strains the strains pathogenic for mouce were 26 strains, and coagulase-positive strains were 18 strains, the strains which hemolyse the blood of horse and rabbit were 45 and 40 strains each. 5.8 per cent of the strains isolated from normal milk was the strains pathogenic for mouse. 3) Since the rate of isolation of pathogenic Micrococcaceae from the milk of udder suffering from mastitis is not largely different from that of normal milk, it may be of little possibility that the main causative agent for mastities is Micrococcaceae. 4) Since the production of pigment is pretty parallel to the other many characters, the conventional method to classify Staphylococcus with pigments produced is thought to be satisfactory. The classification of the genus owing to the arrengement of cells ecept for Sarcina group is thought to be little meaning. 5) Coagulase and hemolysis are not paralell to the pathogenicity so closely as thought generally. It seems that there is somewhat the relationship between the pathogenicity and MR reaction, nitrate reduction, hydrogen sulfide production, methylene blue reduction, mannitol fermentation or lactose fermentation. Gelatin liquefaction, the growth on crystal violet medium and the resistance to 7.5 percent natrium chloride seemed not to be paralell to the pathogenicity