According to a survey performed in 2015-2016 by the American Pet Products Association, 86 percent of dogs in American households are spayed or neutered. That’s fantastic because those dogs are protected against a number of maladies that “intact” (that’s veterinary-speak for unsprayed females and unneutered males) dogs are at risk for, such as mammary and testicular cancers, prostatic abscesses and the life-threatening uterine infection known as pyometra.
Intact dogs that are allowed to mate are also at risk for contracting infectious diseases from their partners. Luckily, we see these diseases pretty infrequently because the vast majority of dogs here in the U.S. are spayed or neutered, thus rendering them incapable of breeding and acquiring these diseases. But for those pet parents who allow their dogs to be — ahem — sexually active, be aware that these diseases can make your dog quite ill, and avoiding them altogether is another great reason to spay and neuter.
Brucellosis is a disease that is present in a number of different animal populations. The organism that causes the disease in dogs can also affect people, making it what we call a “zoonotic” disease. Sometimes dogs with brucellosis have no symptoms, but it can cause joint and spinal pain, painful eye problems and abortion of puppies in the case of pregnant females. Brucellosis does respond to antibiotic therapy, but it can take weeks of treatment and relapses occur even after the dog has apparently cleared the organism from its system.
Brucellosis is most commonly transmitted between dogs during mating, although a dog can contract it from an infected dog by inhaling or ingesting bacteria-laden secretions. It’s extremely rare for a spayed or neutered dog to contract brucellosis, however, so preventing sexual activity almost guarantees your dog will be brucellosis-free.
Transmissible venereal tumors
Cancer is likely the most frightening diagnosis you can hear when it comes to your pet. Here’s a type of cancer that’s actually contagious, if you can believe such a thing. And it can be almost universally prevented if only you spay or neuter your dog.
Transmissible venereal tumors are exactly what the name suggests. They’re a type of cancer that is transmitted between dogs that have sexual contact with each other. These tumors typically grow on the skin of the genitalia. Since dogs are butt-sniffers, these tumors have been known to grow inside the nose as well.
TVT can be successfully treated with chemotherapy, but as with most chemotherapy, there can be significant side effects. Again, preventing your dog from engaging in sexual behavior will almost 100 percent guarantee that he doesn’t get this cancer.
Intact dogs, especially the male ones, don’t show a lot of reason when it comes to engaging in sexual behavior. Male dogs can smell an intact female dog in heat up to a mile away, and the urge to go to her and do what comes naturally is pretty much undeniable. Male dogs can sustain injuries and infection of the penis, and female dogs can have substantial trauma to the vulva and vagina when they answer the “call of the wild.”
Even neutered male dogs will show a bit of interest if they are close to an intact female in heat, but without the equipment (i.e. testicles) to really do anything with her they’re safe from these traumatic injuries associated with mating.