Cryptorchidism in Pigs: Undescended Testicles in Boars

Quick Answer
  • Cryptorchidism means one or both testicles did not move down into the scrotum.
  • Many boars act normal, so the problem is often found during a wellness exam or when a pig is scheduled for neuter surgery.
  • A retained testicle can stay in the abdomen or inguinal canal and may keep producing hormones, so your pig may still show intact male behaviors.
  • Treatment usually involves surgical removal of the retained testicle and the descended one, because the condition is considered heritable and the retained testicle can become painful or diseased.
  • If your pig has sudden groin or belly pain, swelling, vomiting, collapse, or severe distress, see your vet immediately.
Estimated cost: $250–$2,500

What Is Cryptorchidism in Pigs?

Cryptorchidism is a developmental condition in which one or both testicles fail to descend into the scrotum. In pigs, the retained testicle may be located in the abdomen or within the inguinal canal. One-sided cryptorchidism is more common than both-sided cryptorchidism, and a boar with one normal descended testicle may still be fertile.

This matters for both pet pigs and breeding boars. A retained testicle still produces male hormones, so your pig may continue to show mounting, odor, territorial behavior, or aggression even if only one testicle is visible. In miniature pet pigs, confirming that both testicles are present before a routine neuter is especially important because cryptorchidism does occur in this group.

For many pet parents, the first clue is simple: the scrotum looks uneven, very small, or empty on one side. Some pigs never show obvious symptoms beyond that. Others are only diagnosed when your vet cannot find both testicles during a pre-surgical exam or while planning castration.

Symptoms of Cryptorchidism in Pigs

  • Only one testicle visible in the scrotum
  • Empty or underdeveloped scrotum on one or both sides
  • Normal boar behavior despite a missing testicle, including mounting, odor, or aggression
  • Firm or painful swelling in the groin
  • Abdominal discomfort, reluctance to move, reduced appetite, or vocalizing with handling
  • Sudden severe pain, collapse, marked swelling, or signs of acute distress

Some pigs with cryptorchidism seem completely healthy apart from a missing testicle. That is why this condition is often missed until puberty, breeding evaluation, or neuter planning. If your pig has only one testicle in the scrotum, schedule an exam with your vet rather than waiting to see if it changes.

When to worry more: contact your vet promptly if your pig develops groin swelling, pain, reduced appetite, or behavior changes. See your vet immediately if there is sudden severe pain, collapse, or a rapidly enlarging swelling, because a retained testicle can occasionally twist or become trapped and painful.

What Causes Cryptorchidism in Pigs?

Cryptorchidism is a congenital developmental defect. That means the problem starts before birth, when the testicle does not complete its normal descent into the scrotum. In swine reproduction references, cryptorchidism is treated as a heritable defect, which is why affected boars should not be used for breeding.

In practical terms, this is usually not something a pet parent caused through daily care. It is more closely tied to genetics and fetal development than to housing, feed, or routine handling after birth. Because of that, prevention focuses more on breeding decisions than on home management.

A retained testicle may sit anywhere along the normal path of descent, from near the kidney to the inguinal canal. Even when it stays hidden, it can still produce testosterone. That is one reason a pig with cryptorchidism may look partly neutered but still behave like an intact boar.

How Is Cryptorchidism in Pigs Diagnosed?

Diagnosis starts with a hands-on exam. Your vet will palpate the scrotum and groin to see whether one or both testicles are missing from the scrotum and whether a retained testicle can be felt in the inguinal area. In many pigs, that exam plus the history is enough to strongly suspect cryptorchidism.

If the retained testicle cannot be felt, your vet may recommend imaging. Ultrasound is often the most practical next step because retained testicles can sometimes be identified with transabdominal ultrasonography. Imaging can help with surgical planning, especially in larger pigs or when the retained testicle is thought to be abdominal.

Before surgery, your vet may also discuss pre-anesthetic bloodwork, body condition, and anesthesia planning. That matters in pigs because body fat, size, age, and stress level can all affect handling and anesthesia safety. In some cases, the diagnosis is fully confirmed during surgery when the retained testicle is located and removed.

Treatment Options for Cryptorchidism in Pigs

Spectrum of Care means you have options. Here are treatment tiers at different price points.

Budget-Conscious Care

$250–$600
Best for: Pet parents who need to confirm the problem first, budget for surgery, or arrange referral to a pig-experienced practice
  • Physical exam with your vet
  • Confirmation that one or both testicles are not in the scrotum
  • Basic pre-surgical planning
  • Monitoring while arranging surgery or referral
  • Behavior and housing guidance to reduce risk from intact boar behaviors
Expected outcome: Short-term outlook is often stable if the pig is comfortable, but the condition does not correct itself and usually still needs surgery.
Consider: Lower upfront cost, but it does not remove the retained testicle. Hormone-driven behaviors may continue, and there remains ongoing risk of pain, torsion, or later disease in the retained tissue.
Most Common

Recommended Standard Treatment

$600–$1,400
Best for: Most pigs with a palpable retained testicle or straightforward unilateral cryptorchidism
  • Exam and surgical planning
  • Sedation or general anesthesia
  • Routine castration plus removal of the retained inguinal testicle when accessible
  • Pain control and perioperative monitoring
  • Discharge instructions and recheck as needed
Expected outcome: Excellent in uncomplicated cases once both testicular tissues are removed and recovery is routine.
Consider: More cost than watchful waiting, and surgery still carries anesthesia and wound-healing risks. In pigs, body size, obesity, and stress can increase complexity.

Advanced / Critical Care

$1,400–$2,500
Best for: Pigs with abdominal retained testicles, large body size, obesity, prior surgical difficulty, severe pain, or suspected torsion or tumor
  • Referral to an exotics, farm animal, or surgery-focused veterinarian
  • Preoperative bloodwork and targeted ultrasound
  • Abdominal cryptorchid surgery or more complex exploratory approach
  • Expanded anesthesia monitoring and stronger perioperative pain-control plan
  • Hospitalization, complication management, and pathology if abnormal tissue is found
Expected outcome: Good to excellent when the retained testicle is successfully located and removed, though recovery may be longer in complex cases.
Consider: Highest cost range and may require travel or referral. The benefit is better planning and support for difficult anatomy or higher-risk anesthesia cases.

Cost estimates as of 2026-03. Actual costs vary by location, clinic, and individual case.

Questions to Ask Your Vet About Cryptorchidism in Pigs

Bring these questions to your vet appointment to get the most out of your visit.

  1. Do you think my pig has one retained testicle or two?
  2. Can you feel the retained testicle in the groin, or do you recommend ultrasound first?
  3. Is this likely to be an inguinal surgery or an abdominal surgery?
  4. What anesthesia and pain-control plan do you recommend for my pig’s size and age?
  5. What cost range should I expect for surgery, medications, and follow-up?
  6. Are there signs of torsion, inflammation, or another urgent complication right now?
  7. How should I manage behavior, housing, and feeding before and after surgery?
  8. Should this pig be excluded from breeding because cryptorchidism is heritable?

How to Prevent Cryptorchidism in Pigs

There is no reliable at-home way to prevent cryptorchidism in an individual pig after conception. Because the condition is considered congenital and heritable, the most meaningful prevention step is breeding selection. Boars with cryptorchidism should not be used for breeding, and source-herd records matter when choosing breeding stock.

For pet pigs, prevention is really early detection and planning. Check with your vet during juvenile exams to confirm that both testicles have descended normally. If one is missing, do not assume it will always come down later. Early identification helps your vet plan the safest surgery before the pig becomes larger, stronger, and harder to anesthetize and handle.

If you are adopting or purchasing a young male pig, ask whether both testicles were seen in the scrotum and whether there is any family history of heritable defects. That will not prevent every case, but it can reduce the chance of bringing a breeding-related problem into a herd or home.

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