Immunity to leptospirosis: renal changes in vaccinated cattle given challenge inoculum
Killinger, A.H.; Taylor, P.L.; Huhn, R.G.; Hanson, L.E.; Mansfield, M.E.
American Journal of Veterinary Research 37(1): 93-94
1976
ISSN/ISBN: 0002-9645 PMID: 1247204 Document Number: 98767
Resistance to renal leptospirosis was demonstrated in cattle vaccinated with Leptospira interrogans serotype pomona bacterin. Fewer vaccinated cattle challenged with L. pomona 12 months after vaccination had kidneys with gross focal lesions in the cortex than did unvaccinated controls. Histological changes characteristically associated with renal leptospirosis occurred less frequently and renal tissue damage was less severe in vaccinated cattle than in unvaccinated controls. The isolation of L. pomona from only one of 29 vaccinated cattle, compared to 7 isolations from 11 unvaccinated cattle, at 26 days after challenge, indicated that mild renal infection occurred only infrequently in vaccinated cattle. It appeared that challenge inoculation of vaccinated cattle with L. pomona stimulated an accelerated secondary immune response in which immunity limited the multiplication of leptospires in the kidney.