Development of a Chemically Altered Pasteurella multocida Vaccinal Strain

Abstract
SUMMARY: The immunogenic properties of a chemically altered strain of Pasteurella multocida were studied. The chemically altered vaccinal strain, 76-63M, afforded calves, swine, and sheep protection against challenge exposure with virulent P multocida organisms. A high degree of protection was elicited in mice and hamsters vaccinated with the experimental vaccine. The chemically altered strain of P multocida compared favorably with reference bacterin standards in inducing resistance to challenge exposure.