Antigenic relationship between the dermonecrotic toxins produced by Pasteurella multocida type D and type A.

Crude dermonecrotic toxins (DNT) were prepared from Pasteurella multocida (P.m.) type D and type A strains isolated from pigs with atrophic rhinitis. Rabbits were immunized with the DNT of P.m. type D. This serum neutralized the DNT of P.m. type A to the same degree as the homologous one both in vitro (cytopathogenicity for tissue culture cells) and in vivo (mouse lethality and dermonecrotic activity in guinea pig).