Clostridium oedematiens: observations on potency assaying

The United States has established a Standard Requirement for the potency testing of biological products containing Clostridium oedematiens belonging to two types: type B (Cl. novyi) and type D (Cl. haemolyticum). Guinea pig testing has provided widely varying results depending on the origin of the animals. The tests reported are intended to determine the efficacity of the vaccines (Cl. novyi and Cl. haemolyticum) depending on the animal tested: guinea pigs, sheep and bovines; they further establish a parallelism between the antitoxin titer and the immunity of the animal.