Anal glands are two small glands or sacs located on either side of a dog's anus. The purpose of the anal glands is known to be the application of pheromone-rich secretion to the outside of the stool in order to mark territory, an important function in most roaming animals.
Most dogs empty these glands on their own whenever they have a bowel movement or during exercise. Dogs that have problems with impacted anal glands usually do so for a variety of reasons. Some dogs may have anal gland problems because they are being fed a low fibre diet. A high fibre diet results in voluminous stools, which tend to naturally "milk" the glands during a bowel movement. Obesity and/or a lack of exercise can result in impacted anal glands because the glands do not get expressed naturally.
When the anal glands fail to empty, most pets simply rub their hind ends along the ground (called "scooting") thereby squeezing and emptying the glands. If unsuccessful, they may become uncomfortable, begin straining, and start excessive licking and biting of the anal area. If left untreated, a rash around the anus may develop due to self-trauma. Some dogs may chase their tails and some dogs undergo changes in temperament.
Taking your dog or cat to your veterinarian when scooting occurs is prudent. Manual expression of the anal glands by a veterinarian often resolves the problem and prevents complications. Repeated expressing of the glands does not seem to increase the frequency of anal gland impaction.
Pets that require constant anal gland emptying should be thoroughly assessed by a veterinarian to make sure that there is no underlying medical problem. For example, pets may rub and lick their rectal area for reasons other than impacted anal glands, such as allergies (e.g. inhalants or food), intestinal parasites (e.g. tapeworms) and tumours. By far, the most common reason for anal gland problems is an infection of the anal glands, called anal saculitis, which requires antibiotics to clear the infection.
If all possible medical causes have been ruled out and the problem still persists, surgery may be a reasonable and effective alternative. While loss of anal sphincter control can be a surgical complication postoperatively, it occurs only rarely. Your veterinarian will be happy to discuss treatment options with you.