Investigation on the distribution of leptospira serovars and its prevalence in bovine in Konkan region, Maharashtra, India

Abstract

Leptospirosis is a neglected most widespread re-emerging global zoonotic disease affecting both animals and humans diversely in developing countries. In this study, investigation was carried out to know the distribution of leptospira serovars and its seroprevalence in bovine population in Konkan region of Maharashtra, where human cases of leptospirosis have been reported periodically. A total of 575 serum samples (Cattle-171; Buffaloes-245; Bullocks-81; Bulls-78) randomly collected from coastal areas (Sindhudurg-174, Raigad-90, Thane-230, Mumbai-81) were tested at 1:100 dilution in microscopic agglutination test (MAT) using live antigens of 18 reference leptospira serovars. The overall seroprevalence of 41.04% (236/575) (CI: 95% 37.01 to 45.20) with 34.5% in cattle, 52.2% in buffaloes, 32.1% in bullocks and 29.4% in bulls was observed. The results of chi-square test revealed that seroprevalence is not independent across the age groups for buffaloes (χ2 =9.98, p <0.01), bulls χ2 =21.26, p<0.01) and bullocks χ2 =10.89, p <0.01), but independent in cattle χ2 =4.97, p >0.05). Among the coastal areas, high prevalence was observed in Mumbai (66/81=81.4%) followed by Thane (87/230=37.8%), Sindhudurg (56/174=32.1%) and Raigad (27/90=30.0%). The prevalence is significant and not independent across the species (χ2 = 22.7, p <0.01) and study regions (χ2 =65.90, p <0.01). The predominant leptospira antibodies against major serovars were Australis (23.61%) followed by Hardjo (19.44%), Hebdomadis (16.67%), Bankinang (15.28%), Icterohaemorrhagiae (14.58%), Kaup (9.03%), Tarassovi (7.64%) etc. determined against frequency of distribution of the serovars. This study supports that bovines may have a role in maintaining Australis serovar and some intermediate species serovars, apart from being a well-known reservoir for Hardjo serovar in bovine in Konkan region of Maharashtra state, India.