04/29/2026
Pigeon Fever in Horses: What Owners Need to Know:
At Brazos Valley Equine Hospitals, we see Pigeon Fever come and go in cycles across Texas. Most years it’s quiet, and other years it shows up across multiple farms. When it does, it creates a lot of concern for horse owners—mostly because of how dramatic it looks.
The good news: most cases are very manageable with the right
approach.
What is Pigeon Fever?
Pigeon Fever is an infection caused by the bacteria Corynebacterium pseudotuberculosis. It lives in the soil and tends to show up more during mild/hot and dry conditions—something we see with Texas drought cycles. The name comes from the classic swelling in the chest (pectoral region), which can resemble a pigeon’s breast. It is not caused by pigeons. You may also hear it called “dryland distemper” or “Colorado strangles.”
How Do Horses Get It?
This is primarily an environmental disease!
Horses are exposed when the bacteria enter through:
· Biting flies (likely the main driver)
· Small cuts or abrasions
· Irritated skin
This is not a highly contagious horse-to-horse disease like some respiratory infections. Instead, it’s more about exposure to contaminated environments and flies moving bacteria between horses. Once it shows up on a property, it can persist in the soil for a long time, which is why farms may see cases recur in future years.
What Does It Look Like?
External Abscesses (Most Common)
This is what most people think of:
· Swelling in the chest, lower neck, or abdomen
· Firm, painful area that gradually softens
· Eventually ruptures and drains thick pus
· Some horses run a fever
These can occasionally cause lameness if deeper muscles are involved, especially in the pectoral or triceps region.
Internal Infection (Less Common, More Serious)
A smaller percentage of horses develop internal abscesses. These are the cases we take much more seriously.
Signs can include:
· Weight loss
· Fever
· Low energy
· Vague or chronic illness
These abscesses most commonly involve the liver, spleen, or kidneys.
Limb Swelling (Rare)
Occasionally, horses will develop severe swelling of a limb with multiple draining tracts. This is uncommon but can be more complicated to manage.
How is It Diagnosed?
In most cases, diagnosis is fairly straightforward based on location and appearance of the swelling.
When needed, we may use:
· Culture of the drainage
· Bloodwork
· Ultrasound to locate deeper abscesses
· Serology when we are concerned about internal infection
The key is determining whether we’re dealing with a simple external abscess or something deeper.
How is It Treated?
External Abscesses:
This is where people often overcomplicate things. Most cases are best managed by:
· Allowing the abscess to mature
· Draining it (either naturally or with veterinary assistance)
· Keeping it clean for several days
Whenever possible, we prefer to lance and drain in a controlled area and collect the discharge rather than letting it contaminate the soil. This helps protect the rest of the property. Antibiotics are usually NOT indicated for simple external abscesses and can actually delay resolution in some cases. That said, treatment is case-by-case—older horses, chronic cases, or deep infections may benefit from antibiotics. The biggest priorities are drainage, cleanliness, and minimizing contamination of the environment.
Internal Abscesses:
These are a completely different situation. Treatment typically involves:
· Long-term antibiotics (often 1–4 months)
· Careful monitoring
· Repeat imaging and lab work
These cases require commitment, but many horses do well with appropriate treatment when caught early.
Is It Contagious?
Not in the way most people think. It spreads through:
· Pus from abscesses
· Contaminated soil
· Flies
It does not spread as efficiently through direct horse contact like respiratory diseases. That said, once it’s on a farm, it can affect multiple horses if conditions allow.
How Do You Prevent It?
There is currently no reliable vaccine. A vaccine was previously available but was pulled due to side effects. Prevention comes down to management:
· Fly control is critical
· Keep stalls and paddocks as clean as possible
· Don’t share buckets or equipment unnecessarily
· Don’t place hoses into multiple water buckets
· Isolate horses with draining abscesses when practical
· Handle affected horses last when possible
What about fans?
Fans are one of the most underutilized tools we have for fly control. Flies are weak fliers and avoid moving air. Even a moderate fan significantly reduces fly landings. This is especially effective in stalls, barns, and shaded areas
From a practical standpoint; If you can keep air moving, you can dramatically reduce fly pressure. Fans won’t eliminate flies, but they reduce biting frequency—and that directly reduces the risk of infection.
When draining abscesses, it’s important to:
· Avoid contaminating soil
· Use areas that can be cleaned (concrete, mats, etc.)
· Dispose of discharge appropriately
Good management makes a significant difference in limiting spread.
When Should You Call Your Veterinarian?
Give us a call if you see:
· Swelling in the chest, neck, or abdomen
· Fever
· Sudden lameness with swelling
· Weight loss or unexplained illness
Early evaluation helps us determine whether this is a simple case or something more significant.
Bottom Line -
Pigeon Fever is common in Texas and tends to come in cycles. We believe we are in the beginning of one of those cycles. Most cases are external abscesses and resolve well. Internal infections are less common but require aggressive treatment. It is more of a fly and environment problem than a highly contagious disease. Fly control and environmental management are your best prevention tools!
Need Help?
If you think your horse may have Pigeon Fever, don’t panic—but don’t ignore it either. Call Brazos Valley Equine Hospitals and we’ll help you decide what needs to be done and what can safely be managed at home.
This post includes a photo from a recently seen case. A video demonstrating drainage from this external abscess will be shared in the comments.
*Viewer discretion advised*
