VACCINE BASED ON ATTENUATED HAEMOPHILUS SOMNUS

摘要

The present invention provides a method forprotect-ing cattle from diseases such as septicemia, pneumonia orabortion by immunizing them with an H. somnus vaccine.Provided are natural isolates of H. somnus strains that haveone or more important features of such vaccine,including, sensitivy to killing in complement-containing bovineserum, lack of expression of immunoglobulin bindingproteins, expression of protective antigens and a reduction inthe release of endotoxin during growth. Vaccines usingH--somnus having these and other features also can bepre-pared from natural isolates of asymtomatic carriers or frompathogenic organisms by recombinant DNA techniques.