The efficacy of T1 strain broth vaccine against contagious bovine pleuropneumonia: in-contact trials carried out six and twelve months after primary vaccination
Gilbert, F.R.; Davies, G.; Read, W.C.; Turner, G.R.
Veterinary Record 86(2): 29-33
1970
ISSN/ISBN: 0042-4900 PMID: 5460777 Document Number: 22745
Two groups of 16 vaccinated cattle were challenged 6 or 12 months later, together with two groups of 16 unvaccinated controls that had grazed with the vaccinated cattle. Four controls in each group failed to develop c.f. antibody. In the six-month challenge group, the 12 controls with c.f. titres all developed typical pleuropneumonia (CBPP) lesions from which the causal organism was isolated. There were no lesions, and the organism was not isolated from any of the vaccinated cattle.