Contrary to the typical view of animal rescuers who want their adopted pets "fixed", I personally do not recommend routine neutering/spaying of cavies. I prefer sows and boars be diligently kept separate. Companionship can be provided by same sex pairing or even a neighboring cavy in a nearby cage. Any surgery is risky. There is always the chance a cavy has some underlying health condition that may be worsened by the stress of surgery. Infections can occur. Sutures are occasionally ripped or chewed out. Sometimes a cavy will react badly to the anesthesia - or will suffer abnormal stress from the surgery. All these things can occur with any surgery, but it is an acceptable risk IF the surgery is needed to save a cavy's life or correct a medical problem. Neutering is a voluntary, elective surgery.

Cavy neuters are more complicated than dog and cat neuters. The scrotum and testicles on dogs and cats are relatively prominent and normally outside of the body. Inguinal (groin) rings of the cavy are open and testicles can be retracted into the abdomen. Neutering must be done by a cavy experienced vet to reduce risking prolapse of abdominal contents after surgery. Cavies cannot be medically treated like little dogs and cats. Unfortunately, not everyone has access to a qualified "exotics" veterinarian who treats cavies. Also, dogs and cats have much longer legs and don't linger where they've urinated/defecated. Cavies have short little legs and live in their soiled bedding - so the incision site is exposed to more bacteria. Spaying a sow is even more invasive, involved and risky. An incision is made through the abdomen and major organs (uterus and ovaries) are removed.

In most cases a cavy will do fine if surgery is done by a qualified experienced exotics veterinarian and if proper aftercare is given. However, occasionally a cavy will die during or after surgery - or will have difficulty recovering from surgery and require extra care. This is something anybody considering neutering should be aware of.

I have had only 2 boars neutered. One did just fine, the other died 10 days after surgery. A gross autopsy was done, the neuter site looked fine/incision looked fine. The boar may have had some undetected health problem that worsened from the stress of surgery. Both boars seemed very strong and healthy before surgery - both boars were done by a vet experienced with exotics. Both boars received proper aftercare. A friend had her adult boar neutered by another vet that specializes in exotics, her boar died 3 days after surgery. Yet another friend had a boar neutered at the same clinic by an experienced vet. She ended up syringe feeding her boar for months when he had a very difficult time recovering. She did manage to pull him through, but it took a year to regain the weight he lost after surgery.

There is no guarantee that neutered boars will then get along with each other or any other cavy. Neutered boars are sometimes still very humpy and macho. This is more likely in boars neutered after sexual maturity. The boar that quit eating after neutering still lives alone - even though my friend has tried him with several sows. The boar makes such a pest of himself chasing and humping that the sows get irritated and snappy with him.

We currently have about 68 cavies at the shelter. Except for a handful of prima donna's all are kept in same sex pairs or trios. Sows with sows/boars with boars. None of my boars now are neutered. I find it all depends on the individual animals hitting it off or not. Often 2 very young cavies of the same sex will get along just fine - or an adult will usually accept and be fondly tolerant of a baby. As for boars or sows being more responsive to humans - I don't see a big difference between the sexes. Both can be very sweet, loving, cuddly - or independent and busy. The boars may be more flirty with their humans, swaying their butts and purring loudly when held (same behavior used to court the sows). If you're just starting out with cavies it might be easiest to purchase or adopt 2 littermates of the same sex at the same time - or a mother/daughter or father/son who have been together. That way you don't have to worry about quarantining cavies from different sources separately to avoid spreading disease/bugs to each other. Please do consider adopting from a cavy rescue or animal shelter. It is often possible to get an already bonded pair of same sex cavies this route.

Occasionally seemingly bonded cavies will suddenly, for no apparent reason, stop being buddies. Perhaps somebody has stepped over a line or a youngster has become too cocky for its own good. I have had this happen to both boar and sow pairs, but more so the boys. If the fighting does not stop after a couple days or gets more serious, the cavies may have to be separated. I don't feel it's worth having cavies chew each other up trying to establish a pecking order. I once tried the squirt bottle routine with a couple of boars that suddenly weren't getting along after living together for months. They did indeed stop fighting while I was there to squirt them. One day when I wasn't there to stop the fighting the younger boar ripped a cheek open on the older boar. It could have used a couple stitches, but since it was a Saturday night and we have no nearby emergency cavy clinic - I "glued" the cheek shut with a thick antibiotic ointment. It did heal just fine. I also admitted defeat and separated the boars.

Keeping incompatible cavies in separate but neighboring cages is another option. They still have company - yet also have their own space. Same sex cavies may even learn to socialize while enjoying exercise time in a large open area, then retiring to their separate abodes afterwards. DO NOT try this with a boar and sow though, she could be bred in the wink (or two) of an eye.

The final decision is up to each owner. When done by a qualified cavy veterinarian with proper after care provided by the owner, the majority of cavy neuters are successful. Some owners and rescuers have had dozens of boars neutered with no trouble. I've also heard from many grieving owners that have indeed lost their cavy after neutering. No surgery is risk free, not even a cavy neuter. When YOUR much loved little boar is one of the few that dies from being neutered - statistics aren't much comfort.

I do not want to scare owners away from having necessary surgery done on their cavies. Surgery is sometimes the best or only way to save a cavy's life or correct a medical problem. The key is to find a vet interested in cavies, knowledgeable about cavies and experienced with cavies. I have had literally countless cavy surgeries done over the years. All but a handful have survived and recovered - to live better lives because of the surgery. Some of the animals that did die had such serious medical problems that we knew going in they might not survive the surgery, but the only alternative was euthanasia. In cases where a cavy requires surgery to live or thrive, it's worth the risk.

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