The dog has two anal glands or sacs located at five and seven o’clock on either/both sides of the anal sphincter. The openings of the anal sacs are found by drawing down on the skin of the lower part of the sphincter. By applying a small amount of pressure directly below these openings, these glands can usually be expressed.
These sacs are sometimes referred to as the “scent” glands. In the skunk they serve a protective purpose. In the dog they appear to be of use in territorial marking, and to enable dogs to identify one another. This probably accounts for the fact that dogs greet each other by sniffing the other’s hind end.
The anal sacs are normally emptied by rectal pressure during defecation. The secretion is liquid and brownish with a characteristic odour when a dog is upset, frightened or under pressure. At times it may be thick, yellow, or creamy looking. Anal sacs are also emptied whenever there is sudden contraction of the anal sphincter. Most groomers express the glands before bathing the dog.
In most dogs, it is not necessary to express the glands unless there is a medical reason to do so. However, when frequent odour does pose a problem (for example, in a dog with overactive anal sacs), you can control it by having your veterinarian, or a veterinarian nurse express the anal glands on your next visit.
Impaction of Anal Sacs
Impaction of the anal sacs occur when the sacs fail to empty normally. It is most common in the smaller dog breeds. Some of the common causes are soft stools, small anal sac openings, and overactive anal sacs. Secretions become thick and pasty. If you suspect your dog has impacted anal sacs, see your veterinarian as soon as possible.
Anal Sac Infection (Anal Sacculitis)
This condition complicates impaction. It is recognized by the presence of blood or pus in the secretions. Signs of pain are excessive grooming of anal area and scooting.
Anal Sac Abscess
An abscessed anal sac is recognized by the signs of anal infection with swelling at the site of the gland. The swelling is at first red, then later turns a deep purple, some of these will rupture. See your veterinarian immediately.
Dogs or cats with recurrent anal gland infections need to have their glands emptied on a regular basis. Surgical removal can be considered; however, it is not recommended on a routine basis. The anal gland surgery can pose a threat of faecal incontinence.
Signs of anal gland problems include scooting, excessive grooming of anal area and painful defecation.