Investigation on Efficacy of a Commercial Vaccine for Treatment of Leptospirosis in Cattle

Abstract

The aim of this study was to determinate leptospirosis in cattle and to investigate efficacy of a commercial vaccine in treatment of leptospirosis. Upon observing leptosipirosis specific clinical signs including haematuria and mucosal icterus in 2 heifers and mouse fleshes on the surface of the water reserve of the farm, the clinicians tentatively diagnosed the diseased heifers as leptosiprosis. In addition, 9 heifers had general clinical signs including fever, apathy and tachypnea. Blood samples were collected from 41 heifers kept in the farm, including those exhibiting specific and non-specific clinical signs. All clinically diseased heifers were seropositive for leptospirosis confirmed by Microagglutination Test (MAT). The antibody titers were 1/100 or above in 11 out of 41 heifers (26.8%). All 41 heifers were vaccinated with a specific commercial vaccine (Lepto Shield 5 (R)) developed against leptospirosis. At the forth day of vaccination, one of the diseased heifers died of acute leptospirosis while the others clinically recovered 8 days after vaccination and none of the seropositive heifers showed any clinical signs of the disease. No side effects were observed within a month following vaccination. The results of the present study suggest that Lepto Shield 5 (R) is effective not only for protection but also for treatment of leptospirosis in cattle.