Investigation of the role of exercise in the detection of selected respiratory pathogens from nose wipes collected from healthy horses.
Authors: Wright C A, Lawton K, Barnum S, Craig B W, Farwell B R, Blea J, McCook C, Pusterla N
Journal: Journal of equine veterinary science
Summary
# Editorial Summary: Exercise and Respiratory Pathogen Detection in Healthy Horses Researchers at UC Davis investigated whether physical exercise enhances the detection of respiratory pathogens from nasal samples in clinically healthy horses, potentially offering a non-invasive diagnostic alternative to traditional nasal swabbing. Over 133 horses of varying ages and disciplines underwent nasal wipe collection before and after exercise, with samples analysed for six pathogens: the clinically significant equine herpesviruses (EHV-1 and EHV-4), commensal herpesviruses (EHV-2 and EHV-5), and Streptococcus species. Post-exercise sampling significantly increased detection frequency for EHV-1, EHV-2, EHV-5, and S. zooepidemicus (p < 0.05), though notably the absolute viral and bacterial loads were paradoxically lower in these samples, suggesting exercise mobilises lower concentrations of pathogens into the upper respiratory tract. Given that nose wipes are considerably less invasive than nasopharyngeal swabs yet demonstrated improved detection sensitivity for several key pathogens after exercise, this approach merits consideration for epidemiological surveillance programmes and pre-competition health screening, particularly where repeated sampling is needed to establish shedding status in asymptomatic carriers.
Read the full abstract on PubMed
Practical Takeaways
- •Post-exercise nose wipes are more sensitive than pre-exercise samples for detecting common respiratory viruses and bacteria in healthy horses, offering a practical, less invasive screening method.
- •When testing horses for respiratory pathogens, timing collection post-exercise may increase detection rates, though the clinical significance of this enhanced shedding in asymptomatic animals requires further investigation.
- •Consider post-exercise nose wipe sampling as a potential alternative to more invasive nasal swabs when conducting herd health surveillance for selected respiratory pathogens.
Key Findings
- •Exercise significantly increased detection frequency of EHV-1, EHV-2, EHV-5, and S. zooepidemicus in post-exercise nose wipes compared to pre-exercise samples (p < 0.05).
- •Absolute quantitation of pathogens was significantly lower post-exercise for EHV-2, EHV-5, and S. zooepidemicus (p < 0.05), despite increased detection frequency.
- •EHV-4 and S. equi were detected only in a small number of horses post-exercise.
- •Post-exercise nose wipes may provide a non-invasive alternative to nasal swabs for assessing respiratory pathogen shedding status in healthy horses.