Canine Anal Glands
Canine anal glands or anal sacs are scent glands in dogs. Common anal sac problems include anal sac impaction, anal sac infection, and anal sac abscesses. This page looks at the likely causes and treatment options of anal sac problems, and how to express the canine anal sacs.

Anal glands are a pair of small scent glands which are located on either side of a dog’s anus, slightly below the anal opening, at about the 5 o’clock and 7 o’clock positions in reference to the circumference of the anus.

If you pull down the skin on the lower part of the dog’s anus and look in the two locations as mentioned above, you can see them. The anal glands are connected by tiny ducts to the outside.

Anal sacs vary in size depending on the dog breed. Generally speaking, healthy anal sacs range in size from a pea to a kidney bean.

The dog anal glands produce a unique odor that gives the individual dog his “identity”. The odor on the stool helps the dog to establish territory. That’s also why dogs sniff each other’s rear end as a form of “greeting” or communication.

The anal glands are emptied during defecation by the pressure of stool passing through the anus.

Sometimes, the anal glands are emptied out by forceful contractions of the anal sphincter when the dog is upset or in extreme fear.

Canine Anal Glands

Problems Related to Canine Anal Glands

In a healthy dog, there’s really not much to do about the anal glands. But sometimes, some problems related to a dog’s anal glands may arise, such as:

1. Anal Sac Impaction

Perhaps the most common anal gland problem is anal sac impaction, which means the anal sacs have become too full and are not emptied out completely.

As a result, the sacs become swollen and tender, and the liquid secretion becomes extremely thick, plugging the openings of the anal sacs.

Anal sac impactions may be caused by constipation or infrequent bowel movement.

Sometimes, if the stools are too small or too soft, they cannot put too much pressure on the sacs during defecation. This will also result in anal sac impaction.

Dogs with impacted anal glands will often scoot along the floor. This is the dog’s attempt to empty out the sacs.

The dog may also constantly look, lick, and/or bite at the anus. In addition, the dog’s rear end will give out a powerful foul odor.

Anal gland impactions tend to occur more often in obese dogs and small-breed dogs.

How Do You Know If Your Dog’s Glands Need to be Expressed?

To prevent anal sac impactions, the best way is to check the dog’s anal glands regularly (while grooming) to see if they are empty or not.

Feel the areas where the anal glands are located. If they are full, they can be felt as small, firm lumps. If you can feel the firm lumps, then it’s time to express your dog’s glands.

Also, if your dog is showing some of the signs mentioned above (e.g. scooting on the floor, rear end giving out a foul fishy smell), then you know that it’s time to express your dog’s anal glands.

How To Express A Dog’s Anal Glands

You may want to ask your dog’s groomer or your vet to express your dog’s anal glands, or you can do it at home as well (be sure to wear latex gloves!):

  • Begin by holding up the dog’s tail and pulling it gently upward.
  • With your free hand, hold a couple of Kleenex and place your thumb over one anal gland and your fingers over the other.
  • Press gently in and squeeze.
  • When the sacs empty, you can smell a powerful odor and the discharge is a brown liquid. If the discharge is yellow, bloody, or pus-like, it means that the glands are infected and veterinary care is necessary.

2. Anal Sac Infection and Abscesses

Anal glands can also get infected and abscesses may form.

Signs of infection include swelling on one or both sides of the anus. You can see discharge from the anal glands. The discharge is thin, yellowish, blood-tinged, or pus-like.

Anal sac infection is very painful so the dog will lick, scoot, and even bite at his rear.

Sometimes infected anal sacs will result in an abscess being formed within the gland.

Signs of an abscess include fever and swelling (usually on one side). The swelling will turn from red to deep purple and eventually will rupture through the skin, producing a draining tract.

The dog will experience severe pain and sometimes may develop constipation due to the pain.

If your dog lets you, apply a warm compress on the abscess to help soothe the discomfort and facilitate rupture. However, since it’s very painful for the dog, he may not let you near his rear end! In such a case, it’s best to take him to the vet.

If the abscess does not rupture on its own, it should be surgically lanced by a veterinarian. After lancing, it should be drained and flushed with an antiseptic solution, and the dog is usually placed on an oral antibiotic.

Preventing Anal Gland Problems

Dogs with recurrent anal sac impactions are often recommended to have a high-fiber diet or be supplemented with fiber such as bran or medications such as Metamucil. Adding pure pumpkin puree to your dog’s food on a regular basis is also effective in providing extra fiber to the dog.

The high fiber can bulk up the dog’s stools which will put more pressure on the anal glands during defecation, and hopefully will help the glands express themselves.

Sometimes, surgical removal of the glands (anal sacculectomy) is recommended for dogs with chronic anal gland problems.

The surgical procedure is rather simple but occasionally complications such as fecal incontinence do occur.

If you are not sure if surgery is the right thing for your dog, be sure to discuss this thoroughly with your vet and consider all the pros and cons.