Prevalence of Leptospira serogroup-specific antibodies in cattle associated with reproductive problems in endemic states of India.

In this study, the seroprevalence and distribution of Leptospira in dairy cattle in endemic states of India were investigated in association with reproductive problems of the cattle. A total of 373 cattle serum samples from 45 farms in Maharashtra, Gujarat, Andhra Pradesh, Telangana, Karnataka, Tamil Nadu, Punjab, Haryana, Chhattisgarh, Sikkim and Uttarakhand states were collected from animals with a history of reproductive disorders like abortion, repeat breeding, anoestrus and endometritis, and also from apparently healthy animals. These samples were screened for Leptospira serogroup-specific antibodies by microscopic agglutination test (MAT) using a panel of 18 live reference serovar antigens. The seropositivity of 70.51% (263/373, 95% CI 0.65 to 0.75) was associated with reproductive problems (χ2 = 55.71, p < 0.01) and sampled states (χ2 = 32.99, p < 0.01) and independent of apparently healthy animals (χ2 = 15.6, p > 0.10) and age groups of cattle (χ2 = 0.91, p > 0.10). Further, the odds (risk-relation) of reproductive disorders was 5.29 compared to apparently healthy animals (0.25 odds). The frequency distribution of predominant serogroup-specific Leptospira antibodies were determined against the serovars: Hardjo (27.76%), Pyrogenes (18.63%), Canicola and Javanica (17.49%), Hebdomadis (17.11%), Shermani and Panama (16.73%), Djasiman (16.35%), Tarassovi, Grippotyphosa and Pomona (15.97%), Icterohaemorrhagiae (15.59%), Copenhageni (14.83%), Australis (13.69%), Kaup and Hurstbridge (10.65%), Bankinang (10.27%) and Bataviae (9.51%). In conclusion, dairy cattle have a role in maintaining important several serovars besides well-known Hardjo serovar in endemic states of India and warrant mitigating measures to reduce the incidence of cattle leptospirosis including need for an intensive surveillance programme, preventive vaccination and control strategies.