The Other End of the Story – Anal Glands

What, where, why…the yucky stuff !

Anal glands are two small scent glands, located under the skin on either side of the rectum. They are present in both dogs and cats. They can reach the size of small grapes when full of secretion, and are connected to the mucosal edge of the rectum by two small ducts. They are designed to empty their secretion onto the animal’s bowel motions, being stimulated to contract by the stretching of the anal sphincter muscle when stools are passed. If your dog has never had a problem with them, you are unlikely to know they even exist.

In the canine world, dogs mark out their territorial boundaries using their urine (which is also scented), and faeces. The unique scent produced by each dog’s anal glands sends out a clear message as to “who’s turf you are on”. The scent produced by the animal’s anal gland is totally unique to that animal, (as unique as a human’s fingerprint) and acts as an identifier to other dogs. Given that a dog’s sense of smell is over 10,000 times greater than a human’s, it makes sense that such a strong smell to we humans (if you are familiar with the “potent” smell of anal gland secretion) must be incredibly powerful to a dog. This is also the reason why when unfamiliar dogs meet, they always indulge in session of tail lifting and bottom sniffing….the canine equivalent of a hand shake and formal introduction.

So what goes wrong ?

Anal gland blockage, or infection, is a common problem in domestic dogs, and occasionally in cats. The classic signs of anal gland problems in dogs, is “scooting”. Scooting is the term used to describe a dog when it drags it’s bottom along the ground. This is commonly mistaken as a sign of worms (tapeworm infestation can occasionally cause scooting), but is far more likely to be anal gland irritation. Dogs will also lick and chew at the base of their tail, or around the general area of the rectum, in an attempt to relieve the irritation. If an anal gland becomes blocked, the secretion continues to build up in the gland, causing it to swell, and become painful. If it remains blocked for a long enough period of time, it will become infected, and can continue on to burst, and form an anal gland abscess.

What happens then ?

Recurring anal gland blockage is also increasingly common. As a general rule, it is relatively easy for you vet to diagnose, and may often be noticed during a routine check up or vaccination. Expressing, or unblocking, the gland(s) is an unpleasant job, for both dog, owner, and veterinarian. It is achieved by physically squeezing the glands, either externally, or per rectum, and manually removing the secretion build up. It can be quite painful for the dog, if the glands are very blocked, or infected. And the smell…aaaagh !! ….it doesn’t get much worse, and I’ve smelt some pretty bad things, as a vet!

Once the glands have been expressed, the signs of irritation will usually disappear quickly, unless they are already infected. But it is unfortunately common that they can be blocked and full again within months. If infection has occurred, there can be permanent changes and scarring of the gland and ducts, that can prevent normal emptying. These dogs end up with chronic anal gland problems, and can be regular visitors to the vet clinic.

Chronic blockage and infection

If your dog has developed chronic infection and / or blockage of the anal glands, there are only a few alternatives. A normal course of antibiotics does little to clear up anal gland infections, because the gland has very little blood supply, and the source of the infection (the secretion) is constant. Your vet may offer to flush out the anal glands, under sedation or anaesthetic, and implant an antibiotic directly into the glands. This can work about 50% of the time. If it doesn’t work, or the problem is obviously too severe, then the only other choice is to surgically remove the glands. This procedure is not easy, and not without potential complications. To remove the glands under surgical anaesthesia, first they are emptied, and then filled with a quick set gel, via the ducts. They are then carefully dissected out, using the gel to outline the gland. Leaving even a small piece of glandular tissue can result in ongoing problems. Also, due to their proximity to the anal sphincter muscle, any damage to this muscle during surgery, can result in ongoing faecal incontinence, which is obviously disastrous.

So what is the answer ?

Like most diseases, prevention is better than cure. But even for the badly affected dogs out there, there are a few simple tricks that can help enormously. The key to correcting anal gland dysfunction, is to understand what is going wrong. The principle cause of dysfunction is improper emptying of the glands. It is a lack of stimulation to the glands, to fully empty.

This, quite simply, is caused by a lack of faecal bulk. Without correct faecal bulk, the anal sphincter muscle is not stretched, and the glands are not forced to empty. This lack of faecal bulk has been caused by two major changes to the average domestic dog’s lifestyle. Firstly, the confinement of modern dogs, to the average back yard, has significantly reduced the normal roaming and scavenging habits of dog’s. A wild dog will eat an incredible range of indigestible material every day, including bark, wood, vegetation, clay and soil, feathers and fur, bones…etc. A vast amount of this material is passed by the dog in its daily faeces. The resultant faecal motions are large and firm, and cause full stretching of the anal sphincter, and complete anal gland emptying. The second major change to modern dog’s has been the introduction of commercial pet foods. These processed diets are extremely low in residual faecal bulk and consistency (most readers I am sure, can relate to a tin of food going in, and coming, out looking the same ). In fact, many premium dog foods are designed specifically to reduce faecal volume…how convenient. But at what price ?

It is precisely this lack of stool bulk, normally provided by a dog’s natural scavenging habits, and raw food diet, that is resulting in the anal gland epidemic we face today in veterinary medicine.

So the simplest answer to correcting anal gland dysfunction is to replace faecal bulk. Raw bones provide an excellent natural source of faecal bulking. The digestion of raw bones produces those characteristic hard “white” dog motions you often see. If you feed bones every other day, your dogs are extremely unlikely to get anal gland problems. The other very simple form of faecal bulk I use, is whole grain oats, a key ingredient in Vets All Natural Complete Mix. Whole oats are indigestible, and will pass through a dog’s digestive tract and appear in the faeces intact. Adding Complete Mix, soaked in water per instructions, will create good firm stools at the other end. The end result, pardon the pun, will be normal functioning anal glands.

This article was written and authorised by:

Dr Bruce Syme BVSc (Hons)
Founder of Vets All Natural

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Dr Bruce Syme is a practicing vet and animal lover who founded Vets All Natural in 1996 with a simple mission, to “Improve the health and longevity of dogs and cats”. Dr Bruce is an expert in natural pet nutrition, has spoken at the Australian Veterinary Association Annual Conference, and provides regular comment on TV and Radio.
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Disclaimer: The entire contents of this article are based upon the opinions of Dr. Bruce Syme, unless otherwise noted. The information is not intended as medical advice, it simply shares the knowledge and information from the research and experience of Dr. Bruce and his community. Pet health care decisions should be based upon your research and in partnership with a qualified pet health care professional.
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