By Wendy C. Brooks, DVM, DipABVP
Educational Director, VeterinaryPartner.com
More Than You Ever Wanted To Know About Anal Sacs, or Why Is My Pet Scooting?
Where are the anal sacs?
Illustration by Dr. Wendy Brooks, animation by Tamara Rees of VIN.
Should I Do This Myself?
Maybe not. Most people don't want to do anything like this and are more than happy to have a professional take care of it. Less squeamish pet owners may want to try it. The problem is that no matter what anal sac expression technique you use, it is not generally a one-person job. Pets tend not to appreciate having their anal area manipulated, and even the most docile animal may bite. Squirming, at the very least, is expected, so a helper experienced in animal restraint is likely going to be needed to control the front end of the pet. All things considered, anal sac expression may be something best left to anal sac professionals.
What On Earth Are Anal Sacs?
Anal sacs (also called anal glands) are two small glands just inside your pet's anus. The material secreted into these sacs is thick, oily, stinky, and is commonly described as smelling fishy. Most wild animals can empty these glands voluntarily for scent marking or in self-defense (like a skunk might do); however, domestic animals have largely lost their ability to empty these sacs voluntarily. Walking around and normal defecation serve to empty the sacs, but some animals become unable to empty their sacs on their own at all. The sacs become impacted and uncomfortable.
Dogs with impacted anal sacs usually scoot their rear on the ground in an attempt to empty the glands. Some dogs will lick their anal area, and other dogs will chase their tails. Cats often lick the fur off just under their tails. Some animals are simply vaguely uncomfortable, holding their tails down, shivering, hiding, or showing reluctance to walk. Strangely, some animals seem to refer to their discomfort with their ears and scratch and shake their ears as if they have an ear infection.
What To Do About Scooting?
The first step is to check the anal sacs when any pet has a history of scooting. The anal sacs can be emptied in one of two ways.
How to empty the anal sacs
How to empty the anal sacs. Graphic by Tamara Rees of VIN
Externally: Hold up a rag or tissue to the anus and squeeze both sides of the anal area. If the secretion is very pasty, this method may be inadequate to empty the sacs.
Internally: Insert a lubricated, gloved finger in the anus and squeeze the sac between the thumb and forefinger into a tissue held externally. The full anal gland feels like a grape in the location, as shown in the top illustration. The emptying procedure is repeated on the opposite side.
What if Scooting Continues?
If scooting continues for more than a few days after sac emptying, the sacs should be re-checked. For some individuals, it takes emptying anal glands several times in a row before the sacs stay emptied.
If the sacs are empty and scooting is persisting, another cause (such as itchy skin, tapeworms, or even lower back pain) should be pursued.
What Happens if an Impacted Sac Doesn't Get Emptied?
An abscess can form and rupture out through the skin. This is a painful, messy, and smelly condition often mistaken for rectal bleeding. If an anal sac abscess forms, it must be properly treated by your veterinarian. Antibiotics and probably pain medication will be needed.
How Often Should Anal Sacs Be Emptied?
This is a highly individual situation. The best recommendation is to let the pet tell you when the sacs are full. If the pet starts scooting again, it is time to bring him in.
What if My Pet's Sacs Seem to Require Emptying All The Time?
To avoid the expense of having the sacs emptied, you can learn to empty them yourself at home, but most people feel it is well worth having someone else perform this service. A non-invasive technique that helps some patients is a change to a high-fiber diet. This will produce a bulkier stool that may be more effective in emptying the sac as it passes by. There are also assorted supplements marketed for this use that can be tried. Recently, fiber supplements have been marketed for the same effect. Ask your veterinarian about fiber options for your pet.
If the sacs need to be emptied every few weeks or more, you may opt to have the sacs permanently removed. This is generally considered to be a relatively simple procedure by experienced surgeons, but there are some pitfalls a pet owner should be aware of. The anal sac area is complicated by many local nerves controlling fecal continence, and we do not want to disrupt these. Further, the fact that any change in the local musculature of the anal sphincter region can affect fecal continence, and we do not want to disrupt that, either. (Removing one sac and waiting for complete healing before removing the other sac will greatly reduce the chance of this particular complication.)
If the anal glands have ruptured in the past, there can be a lot of scarring, and the anatomy will be distorted, making surgery more difficult and preservation of the normal local structures more difficult. Draining tracts can develop after surgery if the gland is not completely removed, necessitating a second surgery. On the flip side, of course, is that anal sac expression will never again be needed.
Many people own pets for years without ever learning that anal sacs exist at all, and the wives' tale that worms cause scooting erroneously continues. If you have further questions about anal gland disease, ask your veterinarian.