Anal Glands: Your Dog’s Scent Maker

What is the Purpose of a Dog's Anal Sac?

There are a few theories as to why dogs have anal sacs and what purpose they serve. Some say the excretion from the anal gland act as a territorial scent marker. Others argue the excretion acts as a lubricant that helps a dog pass a hard stool.

Like it or not, your dog is a predator. And as such your dog has two anal sacs, also called anal glands, located on the lower sides of his anus. They produce an excretion with a scent that identifies him and tells other dogs such things as your dog’s sex, health and approximate age.

These sacs express (excrete) this fluid when the dog has a bowel movement.

A poor diet or an inherited biological problem can cause the sac to malfunction. And if the sac doesn’t empty as designed, it can become impacted and make bowel movements difficult, even painful.

It’s not uncommon to see a dog attempt to relieve the discomfort of an impacted anal gland by biting at his butt or scooting it across the ground. This activity could damage the delicate tissue around the dog’s anus, so it’s best to get your dog to your vet as soon as possible.

Your vet can manually express the glands – a smelly process Your vet or a groomer can teach you how to do it, if you’re up to the challenge. But most owners prefer to pay to have it done.