Updated June 1, 2021
If you’re used to dogs or cats in your life, you might already know the importance of spaying and neutering. The reasons for spaying and neutering pigs are largely the same, but some unique characteristics of pigs elevate the procedure to one critical for their health and safety.
Why Is Spaying And Neutering Important?
Male pigs should be neutered to prevent unexpected fatherhood (some breeds can become sexually active as soon as two months old!). Neutering also:
- Reduces confrontational behaviors towards other pigs, people, and their surroundings
- Prevents overly strong body odor
- Reduces their impulse to wander away from home
- Reduces their impulse to mark their territory
- Reduces the likelihood of testicular tumors and prostate infections which are endemic in unaltered males.
Female pigs should be spayed to eliminate pregnancy risks (a possibility as early as three months old in some breeds!). Spaying also:
- Eliminates their monthly heat cycle and its associated behavioral challenges. Female pigs in heat can become confrontational and attempt to mount humans and other pigs, potentially creating the risk of permanent spinal damage.
- Practically eliminates the risk of developing Pyometra
- Greatly lowers the risk of uterine infections, tumors, and other reproductive diseases. Unaltered female pigs face a substantial chance of death from reproductive cancer or illness (signs of uterine cancer typically develop between 4 to 6 years of age), and they typically live half as long as their spayed counterparts.
At What Age Should A Pig Be Spayed Or Neutered?
The bigger and older a pig gets (especially female pigs, and doubly so if she develops tumors), the more complex, dangerous, and expensive the operation will become. Excess fat is especially dangerous as it makes anesthesia less predictable and will contribute to a longer recovery phase. For routine spay/ neuter surgery (versus surgery in response to a health issue), it’s important to work with your veterinarian to make sure the individual is healthy enough for the procedure. In some situations, they may recommend waiting for certain health challenges to resolve before performing the surgery.
If the individual is very young, consult a qualified veterinarian to see when they suggest performing the procedure. As a general rule, male pigs should be neutered as soon as possible. The age at which a female should be spayed may depend on whether or not a laparoscopic ovariectomy or full spay surgery will be performed. Your veterinarian will be best able to advise you.
As a note, spaying and neutering procedures in pigs, while similar to cats and dogs, have important differences which could prove fatal if not recognized and understood. Therefore, it is important to work with a veterinarian who has experience performing these procedures in pigs specifically. If possible, it’s helpful to work with a veterinarian who has experience with pigs of similar breeds to your residents (that is, if you care for large breed pigs, it’s helpful to work with a veterinarian who has experience performing these procedures in large breed pigs), but aside from an increased risk for scrotal hernia in potbellied pigs (discussed below), the procedures are largely the same.
With surgery and anesthesia, comes risk. However, in healthy pig residents, these risks are outweighed by the long-term benefits that come with spaying and neutering. We recommend talking with your veterinarian about potential risks and complications that come with the procedure, generally, as well as requesting a pre-anesthetic exam to identify any underlying conditions that may put the individual at an increased risk of developing complications during anesthesia. If one of your residents is at an increased risk due to a chronic health issue or other factor, your veterinarian may refer you to a specialty clinic for the procedure, or they may advise against surgery altogether, in which case you will need to take other steps to ensure there is no risk of breeding.
Talk to your veterinarian about administering injectable sedation prior to inhalational anesthesia, especially sedatives that can be reversed if needed. This practice can lead to a shorter recovery time as well as offer additional pain relief.
Male Pig Complications
If a male pig has Cryptorchidism (one or both testicles are undescended), the neutering process will be much more expensive and invasive because the veterinarian will have to cut into his abdominal cavity in order to remove any internal testes. If this isn’t done, not only will the pig have the same hormonal urges as if he hadn’t gotten neutered, but it also creates a significantly higher risk of cancer, testicular torsion, estrogen toxicity, bone marrow complications, and excess testosterone production.
There’s a chance that a male pig’s preputial diverticulum (a sac inside the penile opening) might fill with semen, urine, and other body waste. Bacteria can breed there as a result, causing infection or a terrible odor. It tends to shrivel up in young neutered males without issue after surgery, but older pigs might need it removed separately from their neutering. You might want to discuss this possibility with your veterinarian.
In some male pigs (especially potbellied pigs), neutering can lead to a gap in the inguinal canal, which is a small opening in their abdominal wall between the abdominal cavity and their scrotum. This could allow contents of the abdominal cavity to enter their scrotum. This is known as a scrotal hernia, and can pose a life threatening emergency. It’s crucial to discuss this possibility with your veterinarian and ask about suturing the inguinal ring when the pig is neutered.
Female Pig Complications
Female pigs are highly prone to complications such as abdominal hernias when they are fully spayed, due to their quick growing and rather thin body cavities. The secondary surgery to repair the hernia makes recovery more difficult and lengthy. In order to avoid this complication and greatly reduce recovery time, pigs can have laparoscopic ovariectomies, where only their ovaries are removed in a much less invasive procedure. In Farm Animal Surgery, Second Edition, Dr. Richard P. Hackett and Dr. Susan L. Fubini discuss their experience with this procedure in pigs- between 2006 and 2015 their practice performed 89 elective spay procedures on a mix of potbellied and large breed pigs, including many sanctuary pig residents. Of the 89 elective spays, “ovariectomy without hysterectomy [removal of the uterus] was performed in 78 pigs, and ovariohysterectomy [removal of both ovaries and uterus] was performed in 11 cases. Most (73%) of the ovariectomies were done laparoscopically, and simultaneous hysterectomy was not attempted due to additional anesthetic time and greater risk of complications. Leaving the uterus does, at least theoretically, leave the door open for pyometra or uterine neoplasia later in life, but substantial studies in dogs indicate that the risks of such problems are negligible in animals ovariectomized at a young age.” Anecdotal information from the sanctuary community suggests that ovariectomy in young pigs reduces the risk of reproductive cancer in female pigs comparably to full spays. Certain veterinary hospitals are comfortable performing laparoscopic ovariectomies on pigs. If your local veterinary hospital is not, ask your veterinarian if they would be willing to have a discussion with an expert who is knowledgeable in this procedure.
If a female pig is in heat or pregnant, spaying is considerably more dangerous. Wait until she’s out of heat, or if she’s pregnant, consult your veterinarian as soon as possible about safe options.
Postoperative Care And Considerations
Ask your veterinarian about postoperative care, especially specific problems that may come up like appetite issues, vomiting, and incision care. Because of their extra fat and general body composition, spaying or neutering a pig is much more painful than it is in a smaller mammal like a dog or a cat. Excessive pain can slow healing and lead to digestive issues like ulcers and bowel obstructions, so make sure that the pig comes home with good pain management medication. Never give aspirin after surgery, as it can increase bleeding. If a recovering resident does not have a bowel movement within the first 24 hours following surgery, be sure to contact your veterinarian. They can recommend an appropriate laxative treatment and adding canned pumpkin to their food may also help. For ulcer prevention, talk to your veterinarian about administering a gastroprotectant at the time of surgery and keeping the individual on a gastroprotectant while on any non-steroidal anti-inflammatory (NSAID) treatments. Be on the lookout for fevers, as pigs cannot easily regulate their body temperature. Prolapse can also occur as a side-effect, so monitor their health carefully during the recovery phase!
The individual will need time to recover apart from other pigs. Pig roughhousing could easily lead to an injury or even rip open surgical incisions. Because pigs will smell different when they get home from surgery, other pigs may react confrontationally to this “new” friend in the pen. Pigs are very sensitive to smell, and even previously friendly pigs might be hostile after surgery. A recovering pig needs a clean, quiet, and dry place to recover for at least ten days before reintroduction to other pigs. You may have to keep their incision dry for up to two weeks, which means no baths, no pools, and no mud. Female pigs might end up peeing unexpectedly a fair bit more due to a sore abdomen. This should abate as they heal.
After spaying or neutering, it will take around two weeks for their hormones to dissipate and their moods to stabilize. Male pigs may no longer produce semen but may still be capable of impregnating females for up to a month due to stored semen.
“Ovariectomy For Sterilization In A Pet Pig” and “Choice Of Procedure: Laparoscopic Ovariectomy vs. Open Ovariectomy Or Ovariohysterectomy” (page 627) from Farm Animal Surgery, Second Edition | Susan L. Fubini, DVM, Dipl ACVS and Norm G. Ducharme, DMV, MSc, Dipl ACVS