Prevalence of leptospiral titres in normal horses.

This study focuses on testing the presence of leptospiral titres in clinically normal horses across eleven locations in Queensland, revealing that 33% of tested horses reacted positively to one or more serovars of Leptospira interrogans.

Methodology

• The research was based on serum samples collected from 479 horses exhibiting no clinical symptoms across 11 varied locations in Queensland. This large and diverse sample size would enhance the overall validity of the study’s findings.
• The serum samples were then assessed using a microscopic agglutination test, which is a standard technique to identify antibodies against common Leptospira serovars.

Findings

• Out of all the samples tested, 157 of the serums, representing 33%, reacted positively to at least one serovar of Leptospira interrogans, indicating exposure to the bacteria.
• The prevalence of each serovar among all tested horses was as follows: 30.5% for pomona, 23.9% for icterohaemorrhagiae, 18.8% for tarassovi, 12.2% for hardjo, 8.6% for canicola, 3.6% for grippotyphosa, and 2% for australis.
• The results showed a marked variation based on geographical conditions and climate. There was a significantly higher prevalence of positive horses in tropical areas as compared to subtropical areas, but no difference was observed between coastal and non-coastal areas.

Conclusions

• The study provides an insightful analysis of the prevalence of Leptospira interrogans serovars among normal, undisease symptomatic horses across different locations in Queensland.
• The geographical variation observed in the study emphasizes the importance of considering climatic conditions in controlling the spread and exposure of Leptospira interrogans among horses.
• Further studies are necessary to confirm these findings and to ascertain if such variations or prevalence also apply to other species and regions, which can help design effective strategies for the prevention and control of leptospirosis.