Spay and neuter for pet health
In North America, most dog and cat owners who are not breeders have their female pets spayed and their male pets neutered to prevent unwanted pregnancy and to reduce behavioral problems. Virtually all humane societies and animal control agencies require spaying or neutering as a condition of adoption, and many perform the surgery before the puppy or kitten goes home with its new owner.
The operation we refer to as a spay is the surgical removal of the ovaries and the uterus. The neuter is the removal of the testes. Both of these surgeries require general anesthesia. Though the risk of any serious complications from the anesthetic or the surgery is extremely low, it is still a remote possibility. The cost of the procedure also is a concern for many pet owners, and most humane organizations offer low-cost spays and neuters, subsidized by taxpayers, grants and donations. Most veterinary hospitals perform these surgeries at cost, or less, as well.
The major benefit of these surgeries is to prevent reproduction in animals not intended for breeding. An additional benefit is limiting certain hormone-driven behaviors that are associated with breeding or attracting a mate, such as urine marking. Aggression and roaming in male dogs are much easier problems to manage in neutered males than they are in “intact” males.
There also are a number of important health benefits for the pets. For female dogs and cats, spaying before sexual maturity dramatically reduces the risk of developing mammary cancer later in life. This is one of the most common cancers in dogs and cats, and spaying is by far the most effective way of preventing it. Another very serious problem that is prevented by spaying is “pyometra,” which is a life-threatening bacterial infection of the uterus. It is usually treated with emergency surgery and about 10 to 15 percent of patients will die despite treatment. Occasionally, it can be treated medically, but this still requires several days in the hospital on fluids and injections, and some patients will still end up at surgery.
The health benefits of neutering male dogs and cats are a little less dramatic than the benefits of spaying females. (Unless you count all the male dogs and cats that get killed by cars because they are out looking for female companionship.) The major health benefit for dogs is a much lower incidence of prostate disease. Benign prostatic hyperplasia which so many older men suffer from, also causes problems in older intact dogs. Also, infections of the prostate gland, which can be life-threatening, are much more common when dogs are not neutered. While neutering does not prevent prostate cancer, it does, obviously, prevent testicular cancer.
Intact male cats don’t seem to have a high incidence of prostate disease, but they face huge health risks from defending a territory and fighting with other male cats. They can get serious injuries, abscesses and are the highest risk group for becoming infected with the Feline Immunodeficiency Virus.
From a societal perspective, spaying and neutering is an important part of the fight against pet overpopulation. If you have rescued a stray cat and had her spayed, you have helped prevent the birth of homeless kittens, kittens that would have had very little chance for a decent life. You have done, on a small scale, what the local shelters do on a larger scale. To end pet overpopulation once and for all, we will probably also need cheap, effective and easily-administered methods of birth control (or nonsurgical sterilization) for pets. Research is under way to try to address this need. However, for the individual pet dog or cat, spaying and neutering still offer the best combination of effective birth control and lower risk of disease.
Carolyn Morrill is a veterinarian who lives in Spokane