High Seroprevalence Against Lawsonia intracellularis Among Adult Horses in Belgium.

The research article discusses a study conducted on adult horses in Belgium, examining their exposure levels to Lawsonia intracellularis, a bacterium that causes equine proliferative enteropathy. The study finds a high percentage of horses tested positive for this bacterium, indicating widespread exposure amongst equine population in Belgium.

Overview of the Study

• The research is focused on Lawsonia intracellularis, a bacterium that results in equine proliferative enteropathy, a disease most commonly found in foals.
• Although there had been isolated cases of this disease in Belgium, the study establishes the presence and extent of this bacterium in the horse population of the country for the first time.
• The study utilized blood samples from healthy adult horses and measured the presence of specific IgG antibodies, which would indicate exposure to the bacterium.

Methodology

• The researchers collected and analysed blood samples from 356 clinically healthy adult horses.
• The presence of specific IgG antibodies against Lawsonia intracellularis was tested through a blocking enzyme-linked immunosorbent assay.
• The results were expressed in terms of percentage of inhibition (PI). A PI of less than 20% was classified as negative, while a PI between 20 and 30% was classified as inconclusive, and a PI of more than 30% was classified as positive.

Results and Conclusion

• The analysis of 356 blood samples showed that 352 horses (98.8%) tested positive for exposure to the bacterium, while 2 horses (0.6%) tested negative, and another 2 horses (0.6%) had inconclusive results.
• The high percentage of seropositive samples demonstrates that a large portion of the Belgian horse population has been exposed to Lawsonia intracellularis, despite apparent clinical health.
• This indicates a significant hidden health concern within the equine population, despite the absence of visible clinical signs in the majority of the population.