EN
Leptospirosis is a major zoonosis throughout the world. The disease can infect several mammal species of farming and domestic animals. The objective of this study was to investigate the prevalence of canine leptospirosis in a rural area of Thailand. One hundred and fifty three non-leptospira vaccinated dogs were selected from the Nakhon Pathom province of Thailand during April 2006 by simple random sampling. The signalment data of age, breed and sex were recorded. All serum samples were reacted with 24 references of leptospira serovars by microscopic agglutination test (MAT). The results showed the highest positivity in dogs aged within 3-6 years (P < 0.05) but were not significantly different between the genders. The most prevalent serovar was tarassovi (30.7%) and its titer ranged from 50 to 400. For all 88 MAT positive sera, 62.5% and 37.5% were positive with multiple and single leptospira serovars, respectively. The high disease prevalence in dogs indicates the high leptospira contamination in this area. However, the potential of the disease transmitted source in dogs is indefinite. Consequently, for effective disease eradication strategies, the local prevalence of leptospira serovars should be utilized for further vaccination.