When female dogs are spayed, they are no longer able to get pregnant. They stop going into heat for good. If your pooch has been spayed yet seems to go into heat, don't assume you're going batty. She might have a condition known as ovarian remnant syndrome.
When a female dog is spayed at a veterinary clinic, her reproductive organs are extracted -- specifically her ovaries and uterus. Once this happens, she no longer goes into heat every six months or so, and no longer displays the classic symptoms of the period of sexual receptiveness. Many owners opt to spay their female dogs as a means of preventing future pregnancies and helping control canine overpopulation. Spaying dogs also offers some health benefits. Spayed dogs aren't as susceptible to breast cancer, for example.
If a dog shows signs of heat post-spaying, it can be the result of oversight during surgery. If any ovarian tissue still lingers in the body after the procedure, it can stay operative and emit hormones. This is called "ovarian remnant syndrome." This syndrome can lead to clear indications of heat. A couple of different factors can cause the syndrome in dogs. The condition can arise from difficulties with the full extraction of the two ovaries during surgery. Ovarian tissue irregularities can trigger the condition, too. The condition also can arise due to a dog having an inordinate amount of ovaries, although this is extremely uncommon.
Dogs who have ovarian remnant syndrome appear to be in heat much to the shock of their confused owners. They frequently have discharge from their vulvae, a typical heat sign. Their vulvae often take on conspicuously swollen appearances. They entice hormonal male canines from significant distances. They permit male dogs to mount them and engage in mating behaviors. If any of these behaviors applies to your spayed dog, take her to the veterinarian immediately to check for the possibility of ovarian remnant syndrome. No breeds are more or less vulnerable to ovarian remnant syndrome than any others, according to veterinarian Margaret V. Root Kustritz, author of "The Dog Breeder's Guide to Successful Breeding and Health Management."
If it turns out that your dog's heatlike behaviors are indeed the response of leftover ovarian tissue, prompt veterinary management is of the essence. Veterinarians frequently employ a surgical procedure to extract lingering ovarian tissue in spayed animals. This process is referred to as an exploratory laparotomy. This surgery doesn't come without possible problems, however. The surgery can be ineffective when veterinary professionals are unable to pinpoint the location of a dog's leftover ovarian tissue, for instance.
If a vet determines that surgery or anesthesia isn't a good idea for a certain dog, she might consider another management option -- use of mibolerone, for one. Mibolerone is a medication that aims to stop dogs from experiencing heat. Veterinarians frequently prescribe medications like mibolerone when surgery is unsuccessful. Only a vet can figure out which specific type of ovarian remnant syndrome management is safest after considering a pet's exact needs and background.
- VeterinaryPartner.com: Ovarian Remnant Syndrome
- PetMD: Estrus Symptoms After Spaying in Dogs
- LSU School of Veterinary Medicine: Canine Ovarian Remnant Syndrome
- The Dog Breeder's Guide to Successful Breeding and Health Management; Margaret V. Root Kustritz
- The Merck/Merial Manual For Pet Health; Cynthia M. Kahn and Scott Line
- ASPCA: Estrus or Heat
- Canine and Feline Endocrinology and Reproduction; Edward C. Feldman and Richard William Nelson
- ASPCA: Spay-Neuter
- Janie Airey/Digital Vision/Getty Images