Study of leptospira infection in buffaloes through molecular and bacteriological techniques

Abstract

In India buffaloes are reared for milk, meat and draft purposes. The economic importance of buffalo rearing in Nagpur is more than cow and contribute major share to the milk production of the district. Apart from its zoonotic implications; Leptospirosis is one of the major causes of abortion, still births, infertility, repeat breeding, decreased milk production, mastitis in ruminants. Considering its endemic nature in India, the present study is aimed at estimating the prevalence of leptospirosis in buffaloes and to establish the possible route of transmission through related canine, rodent and environment. A total of 621(299 each blood and sera and 23 urine) samples collected from 196 apparently healthy and 103 clinically suspected buffaloes and blood samples of 21 stray dogs along with 27 environmental samples were subjected to PCR targeting sec Y gene (202bp) and 16SrRNA gene (331bp).A total of 92 samples including 53 blood samples (buffalo= 45, rodent= 5, canine= 3), 30 buffalo sera samples, four urine samples (buffalo=2 and canine=2) and five environmental samples comprising of 3 water and 2 feed, were processed for isolation of Leptospira in the EMJH medium. Out of 196 blood samples of apparently healthy buffaloes a total of 27 (13.77%) animals were found positive for 16S rRNA gene and 3 (1.53%) for sec Y gene. Similarly, 17.47% (18/103) animals were positive for 16S rRNA gene while 7 (6.79%) for sec Y gene. A total of 30 (15.30%) apparently healthy animals were positive for either 16SrRNA gene or secY gene. Whereas 25 (24.27%) samples from suspected animals were positive for either of the gene. All the urine samples from buffaloes, dogs and environmental samples were negative for presence of both the genes. All the samples processed for isolation of organism turned negative. The accurate and rapid diagnosis of leptospirosis is important and beneficial for surveillance and investigation of transmission dynamics of the disease. Even though the active infection can be readily diagnosed through blood samples it is essential to screen each sample by various tests for proper understandings about the disease distribution.