Spaying and neutering your dog: Options and alternatives

By Dr. Mikel Delgado, PhD and Dr. Nate Ritter, DVM

Recent research has drawn attention to the fact that the standard practice of early spay/neuter (6 months of age or younger) for our dogs may come with increased risk of orthopedic problems and some cancers. These risks may be associated with the hormonal changes that occur when the gonads (reproductive organs) are removed. The estrogen and testosterone produced by the gonads influence multiple organ systems and bodily functions. Some dog owners choose to not spay or neuter their dogs for these or other reasons. 

For owners who want the benefits of spay/neuter, but would also like to retain some of the potentially beneficial hormonal influences of the gonads, there are alternatives.

One option is to spay or neuter your dog at a later age. We’ve covered the effects of early spay/neuter and delaying the procedure in our article on rethinking early spay/neuter, as well as in a webinar featuring Dr. Chris Zink and Dr. James Serpell.

Another option is a gonad-sparing surgical procedure that maintains the production of hormones while preventing reproduction. Procedures available for female dogs include an ovary-sparing spay (OSS) or a tubal ligation; for male dogs the gonad-sparing surgery is called a vasectomy. Let’s take a closer look at the procedures, what they mean, and some of the pros and cons of each.

Female dogs

A traditional spay surgery (ovariohysterectomy) involves the removal of the ovaries and the uterus. In a similar procedure, an ovariectomy, only the ovaries are removed. In either case, there are no gonadal hormones retained. The dog will not have a heat cycle and will be infertile. She will not be at risk of pyometra, even when the uterus is retained, as it is the hormonal influence of the ovaries (progesterone) that increases the risk of pyometra. However, the effects of estrogen are also removed during a spay or ovariectomy.

In an ovary-sparing spay (also called an OSS, or an ovary-sparing hysterectomy), the uterus and cervix are removed. One or both ovaries are retained. Although a dog with an OSS cannot get pregnant, she will still have a heat cycle and some of the associated behaviors. Intact male dogs may be interested in her even though she is not fertile. Dogs with an OSS cannot get pyometra (infection of the uterus) because the uterus has been removed while the effects of estrogen are retained. 

Tubal ligations are rarely performed, although some veterinarians do offer this service. The oviducts are tied off so that the ovaries cannot release eggs into the uterus so the hormones are maintained but the dog cannot reproduce.. Although a dog with a tubal ligation cannot get pregnant, she will still have a heat cycle and some of the associated behaviors. Because the ovaries and uterus are retained, there is still a risk that the dog will develop pyometra.

Male dogs

The most common surgical procedure performed on male dogs is a neuter, or castration. The testicles, and their hormonal influences, are completely removed. Neutered/castrated dogs cannot reproduce.

Dogs who instead have a vasectomy will be infertile, although they may produce some sperm for up to two months after the procedure. The surgery entails cutting or sealing the vas deferens, which is a tube that carries sperm from the testes to the urethra. When the vas deferens is sealed, the sperm cannot be ejaculated. The testicles and the systemic effects of testosterone are maintained, and a vasectomized dog will show “intact male” behavior such as mounting or urine marking.

What’s right for your dog?

We recommend working with your veterinarian, and talking to others who have made similar decisions for their dogs. The Parsemus Foundation provides a list of veterinarians who perform ovary sparing spays and vasectomies. Because these alternatives to traditional spay and neuter are not routinely covered during veterinary training, you may have to travel to get them performed on your dog. 

Good Dog Research: Looking to better understand the effects of these procedures!

To better understand the potential benefits or risks of these alternative surgical procedures, as well as how they compare to traditional spay/neuter or keeping your dog intact, Good Dog is working with Dr. Chris Zink to conduct a survey-based study of dog owners, answering questions about your dog’s reproductive status, health, and behavior. We thank EVERYONE who participated in this study -- we received over 6000 responses. We closed the link in mid-January of 2022, and we hope to publish our results sometime in the first half of 2022.

Stay tuned for future Good Dog research projects!!

Resources

Parsemus Foundation

Pet MD: Vasectomy instead of neuter? (for your dog)

Adams, V. J. (2020). Reproduction in dogs part 1: surgical and non-surgical de-sexing options. Companion Animal, 25(7), 1-9.

Kutzler, M. A. (2020). Gonad-sparing surgical sterilization in dogs. Frontiers in Veterinary Science, 7, 342.