Abstract:
Two fluid media and methods for the cultivation of C. pseudotuberculosis are described. An average yield of 1·3747 and 0·8566 gm of dry cells per litre was obtained in the respective media.
An erythrogenic endotoxin and a pyogenic factor, occurring only in cells grown on blood tryptose agar, have been demonstrated. The endotoxin is inactivated by formalin, but not by phenol, while the reverse is true for the pyogenic factor.
Immunity tests in guinea-pigs have shown that cells containing these antigens have appreciably greater immunizing power than those without. This immunogenicity is reduced to a marked degree when the cells are killed by beta-propiolactone, but not by formalin or phenol.