Corynebacterium Pseudotuberculosis (Pigeon Fever) Update

From the desk of Caleb Harms, 2025 President of the Kentucky Association of Equine Practitioners:

I want to bring to your attention a small but noticeable increase in the number of equine cases of Corynebacterium pseudotuberculosis (Pigeon Fever) here in Kentucky. 

While typically associated with a more western and southern distribution, the UK Veterinary Diagnostic Lab has reported 10 equine Pigeon Fever cases so far this year (8 in October) compared to only 1 in 2024 and no cases reported in 2023 or 2022. 

Corynebacterium pseudotuberculosis Positives by Year – Equine Only Year	Total Cases
2025	11
2024	1
2023	0
2022	0

It should be noted that these cases represent only those that were positively identified via culture of the abscesses associated with C. pseudotuberculosis, making the true number likely under-reported.

Attached is the AAEP’s informative bulletin that you will hopefully find useful as it pertains to typical symptoms, diagnosis, treatment, and wound care.

Please note the contagious nature of the drained purulent discharge that should  be collected and disposed of to prevent exposure to other animals.

Pigeon_Fever_DZ_Guidelines_FINAL_2023(1).pdf

Download PDF • 495KB

Regards,

Caleb J. Harms

2025 President

Kentucky Association of Equine Practitioners

(859) 940-8228 cjharmsdvm@gmail.com