Experiences with herd-specific vaccines against respiratory infections with M. bovis in a large feedlot

In an big herd of feedlot cattle with nearly 3 000 animals per year respira tory infections in a acute and peracute form occurred caused most frequentl y by both Mycoplasma bovis and Mannheimia (Pasteurella) haemolytica. A herd specific vaccine against this infection was produced and used for vaccinat ion beginning at groups of new assembled feetlot calves. Vaccination was sa fe and effective, because losses and treatments are greatly reduced, The im mune response (Ig G) upon vaccination was demonstrated by high titers of an tibodies against Mycoplasma bovis.