Testicular Torsion in Horses: Acute Scrotal Pain and Stallion Emergency
- See your vet immediately if a stallion or colt develops sudden scrotal pain, swelling, marked sensitivity, or colic-like behavior.
- In horses, a mild 180-degree rotation can be an incidental finding, but painful torsion can reduce blood flow and threaten the testicle.
- Common signs include one enlarged painful testicle, restlessness, kicking at the belly, reluctance to move, and abnormal testicular position.
- Diagnosis usually involves a physical exam, scrotal palpation, and ultrasound to assess blood flow and rule out hernia, trauma, orchitis, or post-castration problems.
- Treatment often requires urgent surgery or castration of the affected testicle, especially when pain is significant or blood supply is compromised.
What Is Testicular Torsion in Horses?
Testicular torsion happens when a testicle rotates on the spermatic cord. That twist can reduce or block blood flow, causing sudden pain and swelling. In a horse with true acute torsion, this is an emergency because prolonged loss of circulation can permanently damage the testicle.
There is an important nuance in stallions: Merck notes that a 180-degree rotation may be found in otherwise healthy, symptom-free horses and may not affect fertility. That means not every rotated testicle is an emergency by itself. The problem is when the horse is painful, the scrotum is swollen, or your vet suspects blood flow is being compromised.
For pet parents, the practical takeaway is simple. A painful enlarged scrotum should never be watched at home as if it were routine. Testicular torsion can look like colic, trauma, infection, or even an inguinal hernia, and those conditions need prompt veterinary evaluation.
Symptoms of Testicular Torsion in Horses
- Sudden scrotal pain
- One enlarged or firm testicle
- Scrotal swelling or asymmetry
- Colic-like behavior
- Reluctance to walk or breed
- Abnormal testicular orientation
- General distress
When to worry is easy here: if your horse has sudden scrotal pain, obvious swelling, or colic-like signs, call your vet right away. These signs can overlap with torsion, trauma, orchitis, scrotal hernia, or complications after castration. Waiting can increase the risk of testicular damage and may delay treatment for other emergencies.
What Causes Testicular Torsion in Horses?
Testicular torsion develops when the testicle rotates within the scrotum and twists the spermatic cord. That twist can interfere with venous drainage first, then arterial blood flow if the rotation is severe enough. The result is swelling, congestion, and pain.
In some stallions, partial rotation appears to occur without causing illness. Merck describes 180-degree rotation as common and not clinically important in healthy asymptomatic stallions. Acute painful torsion is different. It is more concerning when the horse suddenly becomes painful, the testicle enlarges, or ultrasound suggests reduced blood flow.
Predisposing factors are not always obvious. A horse may have increased testicular mobility, recent trauma, strenuous activity, or underlying scrotal or inguinal abnormalities. Your vet may also consider other causes of acute scrotal pain, including infection of the testicle or epididymis, scrotal edema, inguinal hernia, or complications related to retained testicular tissue in a cryptorchid horse.
How Is Testicular Torsion in Horses Diagnosed?
Diagnosis starts with an urgent physical exam. Your vet will look at the horse's comfort level, check vital signs, and examine the scrotum for swelling, heat, asymmetry, and pain. Careful palpation helps assess the size, consistency, and orientation of each testicle and epididymis.
Ultrasound is often the most useful next step. It can help your vet evaluate testicular structure, compare sides, and look for changes that suggest impaired circulation. In some cases, Doppler ultrasound may be used to assess blood flow more directly. This imaging also helps rule out other problems such as fluid accumulation, trauma, or herniated intestine in the inguinal region.
Additional testing depends on the case. Your vet may recommend sedation for a safer exam, bloodwork if infection or systemic illness is a concern, and referral to an equine hospital if surgery may be needed. Because some horses with scrotal pain show colic-like signs, your vet may also examine the abdomen and inguinal area to make sure a surgical abdominal emergency is not being missed.
Treatment Options for Testicular Torsion in Horses
Spectrum of Care means you have options. Here are treatment tiers at different price points.
Budget-Conscious Care
- Urgent farm call or clinic exam
- Sedation as needed for safe scrotal examination
- Pain control and anti-inflammatory medication directed by your vet
- Scrotal ultrasound when available
- Short-term monitoring and recheck plan
- Referral discussion if pain persists or blood flow is questionable
Recommended Standard Treatment
- Urgent examination by your vet or referral hospital
- Sedation, analgesia, and anti-inflammatory care
- Scrotal ultrasound with surgical decision-making
- Standing or field castration of the affected descended testicle when appropriate
- Routine perioperative medications and aftercare instructions
- Follow-up exam to monitor swelling, drainage, and comfort
Advanced / Critical Care
- Emergency referral to an equine hospital
- Advanced ultrasound and full reproductive examination
- General anesthesia and surgical exploration
- Inguinal or abdominal surgery if anatomy is complex or a retained testicle is involved
- Hospitalization, IV fluids, and intensive pain management
- Monitoring for complications such as hemorrhage, infection, or concurrent inguinal hernia
Cost estimates as of 2026-03. Actual costs vary by location, clinic, and individual case.
Questions to Ask Your Vet About Testicular Torsion in Horses
Bring these questions to your vet appointment to get the most out of your visit.
- Does this look like true painful torsion, or could it be another cause of scrotal pain such as trauma, infection, or hernia?
- Is ultrasound recommended right away, and what does it tell us about blood flow to the testicle?
- Does my horse need referral to an equine hospital today, or is on-farm treatment reasonable?
- If surgery is needed, what procedure do you recommend and why?
- What are the likely cost ranges for exam, imaging, surgery, and aftercare in this case?
- If only one testicle is affected, what does that mean for future fertility or breeding plans?
- What warning signs after treatment mean I should call you again immediately?
- Are there any concerns about a retained testicle or another reproductive abnormality in my horse?
How to Prevent Testicular Torsion in Horses
There is no guaranteed way to prevent testicular torsion in every horse. Some cases appear to happen because of individual anatomy or testicular mobility that is not obvious until a problem develops. Still, routine reproductive exams in breeding stallions can help your vet identify abnormal testicular orientation, asymmetry, or other concerns before they become urgent.
Prompt attention to scrotal swelling, trauma, or breeding-related discomfort also matters. Do not assume a painful scrotum is minor or that it will settle on its own. Early evaluation gives your vet the best chance to distinguish incidental rotation from a true emergency.
If a horse is not intended for breeding, discussing elective castration with your vet may reduce the risk of future testicular emergencies. For horses with retained testicles or prior reproductive abnormalities, follow-up planning is especially important because cryptorchid and inguinal conditions can complicate diagnosis and treatment.