Why Do Dogs Get Stuck Together When Mating?

Dog mating includes a very distinctive phase known as the copulatory tie. It's unmistakable, since during it, both dogs appear to be completely stuck together.

As we mentioned, this is a normal phase believed to play a role in the species' reproductive success. Because of this, we generally shouldn't intervene. That said, if this tie goes on too long, it could signal a problem.

The Copulatory Tie in Dogs

We can define the tie as the strong physical bond formed between the male and female dog during mating. When the male's member successfully enters the female's reproductive tract, the bulb at its base swells. If this doesn't happen, mating can't occur.

It also can't happen if the bulb swells before the act, since the whole member wouldn't be able to enter. This bulb is called the bulbus glandis. It's a structure of erectile tissue. As it swells during mating, it becomes locked inside the female's reproductive tract, held in place by the female's powerful vulvar constrictor muscles.

The exact function of the tie still isn't entirely clear, but it's believed to stimulate ejaculation and keep the male's member secured until it's finished. That said, it's been confirmed that its duration doesn't affect the chances of fertilization or the number of puppies conceived.

How Long Does the Tie Last in Dogs?

For the tie to effectively fulfill its role of ensuring sperm reaches the female's reproductive tract, it's believed it needs to last at least two or three minutes. That said, it's very common for ties to last anywhere from 10 to 40 minutes.

Given this, a tie is considered excessive whenever it lasts longer than an hour. In these cases, there could be a physical issue preventing the pair from separating.

Why Don't Dogs Separate After Mating?

If dogs have been tied for more than an hour, it's time to step in. This is believed to be due to a spasm in the constrictor ring of the vulva that holds the bulbus glandis in place.

This causes the male's erection to stay locked in place, since a large amount of blood remains trapped in the area. If it goes on for a long time, the dogs are likely to become agitated and start pulling to break free. This only makes the problem worse.

Can You Separate Dogs While They're Tied?

Understanding what's happening physically makes it easy to see why we shouldn't forcibly separate the dogs — doing so could cause serious injuries to both of their genitals. Even if it's an unwanted mating, we need to let it finish naturally and then see a vet afterward. Keep these tips in mind:

• Stay calm. If the dogs are getting agitated, acting nervous will only increase their stress. This can lead to more movement, and consequently, more injury.
• Don't pull on either the male or the female.
• Don't pour water on them.

Separating Two Tied Dogs

First, separating two mating dogs should only be attempted if they've been tied for more than an hour. Less time than that is considered a normal tie, so you should never intervene. It's normal for the female to whine, howl, or growl during the tie — this reaction doesn't mean she needs to be separated from the male.

Separation can be done with a relatively simple maneuver. But if you're very nervous, don't feel capable of doing it, or have tried but haven't succeeded, call your vet. Never force it or keep insisting, since you could hurt the dogs or even get bitten.

How to Separate Two Dogs That Are Tied

To start the separation maneuver, the male needs to be in mounting position. After ejaculating, it's common for the male to swing its front legs to one side of the female, or even turn completely around, staying tied but now facing away from each other. If this happens, you need to carefully move the male.

The goal is to get it back on top of the female, with one front leg on each side of her. Once properly positioned, gently push its hindquarters toward the female.

In other words, the idea is to increase penetration depth so the vulvar ring constricting the bulb stops squeezing. This way, the bulb returns to its normal size and the penis can be released.

Bibliography Carlson and Giffin. 2002. Dog Owner's Home Veterinary Handbook. Madrid: Editorial el Drac.