Located within the muscles adjacent to the anus, at about four and eight o’clock, are two small pouches. These sacs are lined with numerous sebaceous glands, which produce a pungent fluid. The fluid is stored within the sacs and is released onto stool or into the anus via a small duct.
What’s Their Function?
Ever wonder what a dog smells when it sniffs another’s feces? They are smelling the anal gland secretions. Anal gland odors are used for marking territory and possibly for identification. Dogs and cats probably have an unique smell signature to their anal glands. Skunks have well-developed glands and can spray anal gland materials a far distance. Thankfully this wasn’t part of the evolution of dogs and cats!
Does My Pet Really Need Anal Glands?
In short: no. While the scent is used for territorial marking, the utility of anal glands in domestic animals is no longer necessary.
Why Does My Dog Scoot on the Ground?
For wolves and ancestral dogs, anal glands were an important part of their existence. Domesticated dogs have different conformations, diets, stool quality, etc. This can lead to problems expressing anal gland materials, causing infections and discomfort. If related to anal glands, dogs and cats will scoot on the ground in an attempt to empty their glands.
What’s That Fishy Smell When My Pet Is Nervous or Asleep?
Remember that skunks have anal glands and use them as a defense. When frightened or stressed, dogs and cats can release anal gland contents in a similar fashion. Thankfully they don’t project them far! Some dogs may also leak a small amount of fluid when they sleep, leaving behind a brown stain on their bedding.
What Happens If The Sacs Can’t Naturally Be Emptied?
When there’s swelling of the duct or conformational problems restricting outflow, the materials accumulate and can overstretch the sac, causing it to rupture. Frequently the sac will form a much thicker material first, but in time, if not expressed, there’s only so much the sac can hold. Cats are especially prone to having very thickened gland material. The first signs of problems are scooting and a swelling of the skin adjacent to the anus. If a gland ruptures, there will be a second hole next to the anus and it may have fluid and debris around it.
Can A Pet Recover From A Ruptured Anal Gland?
Yes. Ruptured, or abscessed anal glands are painful, but rarely cause long-term problems. Treatment usually involves antibiotics, pain medication, an anti-inflammatory, and warm compresses over the area. Your veterinarian will also assess if the anal gland duct is working properly. In some cases, sedation is used as flushing out the gland and duct can be quite uncomfortable.
Do Anal Glands Develop Tumors?
Mature dogs and cats can develop cancerous masses arising from the anal glands. Most commonly this tumor is an adenocarcinoma. When detected early curative surgery may be possible. In later stages of the disease, the tumor can grow locally and spread to area lymph nodes and even the lungs. Routine palpation of the anal glands is the best way to find these masses early.
How Do I Prevent Anal Gland Problems?
If your pet has trouble expressing the gland on their own, be sure to consult your veterinarian. Low fiber diets, loose stool, conformational issues, allergies, and more may be contributing. For those pets with good stool and a history of scooting or anal gland abscesses or ruptures, routine manual expressing of the anal glands may be necessary.
Can Anal Glands Be Removed?
In cases of chronic anal gland inflammation, discomfort, abscesses, etc, the anal glands may be surgically removed. This is not a routine procedure and is generally performed by a surgical specialist. Many nerves run adjacent to the anal glands and care must be take to not damage these nerves so as to prevent fecal incontinence.
Dan Teich, DVM, is medical director at District Veterinary Hospitals at Eastern Market and Navy Yard