Do you ever see your dog scooting along the floor on their bottom or nibbling at their tails? They could have problems with their anal sacs.
Anal sacs are a pair of small glands positioned just behind your dog’s anus. They are thin-walled and balloon-like with a small exit hole for the liquid they produce; this is a marking scent and the reason that dogs sniff each other’s bottoms.
The way they empty is very simple: as the firm feces slides past the glands, the force of this and the contraction of the anal muscles squeeze out the scent. However, if the dog doesn’t poo for a day or so, or has very soft feces, the glands don’t evacuate and the liquid thickens or becomes gritty, resulting in a blocked exit hole.
This causes the gland to become swollen and sore, hence the scooting and nibbling. Sometimes dogs will even chew at their hind feet. Occasionally, your dog will manage to express some liquid, which produces an extremely unpleasant, and definitely noticeable, odor.
In the vast majority of cases, a visit to your veterinarian – who will manually empty the glands – is enough to relieve the pressure and immediately cure the problem. However, for some dogs, it can become a recurring problem and a vicious cycle. The blocking of the gland irritates the thin-walled lining, causing it to thicken and scar, which in turn shrinks the size of the hole, meaning it is more difficult for the secretions to be expressed.
In most of these cases, a regular squeeze by your vet is enough to keep things under control, however they might also suggest other treatments. The next step is usually to move to a ‘flush and pack,’ and for more severely affected dogs, the vet might even suggest removing the glands.
A ‘flush and pack’ is generally carried out under sedation. A catheter is placed in the sac and sterile fluid is flushed through to thoroughly empty and clean the gland. It is then packed with a soothing antibiotic and anti-inflammatory solution to reduce the swelling and irritation.
Removal of the glands is more significant. It requires a general anesthetic and surgery. As your vet is operating very close to the muscle of the anus, it carries a small risk of post-operative fecal incontinence. This means that it is not a procedure to be undertaken lightly; however, the chances of this are very small.
Anal sacs can also become infected and form abscesses. There is usually no sign of any problem until the abscess bursts to the outside. Then a small hole draining pus and fluid is visible to one side of the anus and the dog is clearly very uncomfortable. In most cases, this can be treated with antibiotics and pain relief medication.
It is also possible for dogs to develop tumors of the anal glands. This is more common in older or middle-aged dogs, and unfortunately, can be quite aggressive and difficult to treat. The first sign is often a swelling beside the anus. Some dogs can also have trouble defecating or produce flat, ribbon-like, feces because of the growth pushing on the rectum. Diagnosis is usually by biopsy and although some masses can be surgically removed, the majority will need chemotherapy or radiotherapy. Given that most of these growths are highly malignant, it is often a terminal condition.
If you suspect that your dog might have anal sac problems, we recommend that you take him to a veterinarian immediately for a thorough examination.