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, showing reluctance to walk or hiding. Strangely, some animals seem to refer their discomfort to their ears and scratch and shake their ears as if an ear infection were present.
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.
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 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.
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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 several sac emptyings 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 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.
If the sacs need to be emptied every few weeks or more, you may opt to have the sacs permanently removed. This procedure is complicated by many local nerves controlling fecal continence, the fact that any change in the local musculature of the anal sphincter area can affect fecal continence, and the fact that with chronic anal sac problems anatomy is distorted. Draining tracts can develop after surgery if the gland is not completely removed. Still, despite these pitfalls anal sac removal is considered a relatively simple surgery by experienced surgeons.
Many people own pets for years without ever learning that anal sacs exist at all and the “wive’s tale” that worms cause scooting erroneously continues. If you have further questions about anal gland disease, ask your veterinarian or go to the Ask a Vet feature on Veterinary Partner’s home page.
Date Published: 1/1/2001
Date Reviewed/Revised: 10/01/2011