They're not the stuff of dinner party conversations, but knowing
how to spot a problem could save your dog a lot of misery.
Picture the scene. You've just washed your dog from top to tail
using the finest shampoo and conditioner money can buy, but even
after drying him, the same horrible fishy odour you noticed
pre-groom is still lingering in your poor nostrils. Sound
'So where's it coming from?' you wonder - even though most of
you have probably guessed by now that your dog's smelly anal glands
are the culprits here.
What are anal glands?
Anal glands (or anal sacs) are relatively small glands found on
either side of your dog's anal opening. Not present in humans, they
are paired sacs located precisely just below the surface of the
skin between the external and internal sphincter muscles, employed
by nature to produce a particularly thick, foul smelling, oily
liquid secreted by glandular tissue for identification and
territory marking. This is the reason dogs smell other dogs'
bottoms when they meet and greet, standing tense with tails erect
to swap their own unique smells (rather like individual
How do dogs empty their anal glands?
Domestic animals like dogs and cats have largely lost their
ability to empty these glands voluntarily - unlike the skunk's
world-famous pungent defence mechanism. Your dog's anal glands may
spontaneously empty just by walking around, especially under times
of stress, creating a very sudden unpleasant change in his odour.
Passing normal firm stools puts natural pressure on the rectum
walls to empty the glands and will, to some degree, help to
lubricate the anal opening in the process, making it easier for
your dog to poo.
How can anal glands become impacted?
Anal glands fill for a number of reasons: most commonly when the
dog's stools are soft (for example, after a few days of diarrhoea),
so insufficient pressure has been exerted to empty the glands.
Whenever they fail to vacate properly there's a chance of becoming
impacted or, even worse, infected - a very painful condition
requiring urgent veterinary treatment.
Impaction results from blockage of the duct leading from the
gland to the opening, with the gland usually becoming non-painful
but swollen. However, infection can result from prolonged impaction
giving the glands a chance to build up nasty bacteria resulting in
pain, increased swelling and, sometimes, even abscesses and
How do I know if my dog may have a problem?
Under most circumstances, anal gland secretions are extremely
minute, so you don't usually see or smell them - though you may
notice your dog's bedding becomes a bit smelly between washes. But
when you can actually smell the odour emanating from your dog's
backside there may be a problem.
Your dog may happily pass through its whole life without ever
having any problems with its anal glands, but not all dogs are so
lucky. Normal anal gland fluid ranges from yellow to tan in colour
and is watery in consistency. Impacted anal gland material is
usually brown or grey, and thick with the occasional presence of
blood or pus indicating infection.
Some dogs seem unable to empty their glands fully on their own,
causing the glands to become impacted and uncomfortable, and the
dogs to drag or 'scoot' their rear-ends along the ground (or more
commonly your brand new cream-coloured carpet) in an attempt to
Other signs include licking or biting around their anal area,
chasing their tail, sitting uncomfortably, or even licking paws -
both front and back - in sheer frustration.
How can this be treated?
Vets will usually treat this by expression of the gland (usually
far too painful in the conscious patient), antibiotics and pain
relief, and even repeated flushes of the glands. Signs of severe
infection might include distinct bulges just beneath the surface on
either side below the anal opening, drainage from the rectum or
even one or more abscesses in the immediate area.
With rare cases of recurrent infection or presence of a specific
type of malignant tumour called an anal sac adrenocarcinoma, anal
glands may be removed surgically by a procedure known as anal
sacculectomy. The potential complications of this specialist type
of surgery, however, make the operation strictly reserved for
essential cases only.
Should I regularly empty my dog's anal glands to prevent this
Be aware that not all dog experts agree the anal glands should
be interfered with in any way - unless the dog is showing signs of
a problem. If you are concerned about anal gland
impaction then speak to your local veterinarian for advice.
Applying pressure to an anal sac impaction or infection could cause
the gland to rupture, and lead to bleeding and painful
complications for your dog.
So if you didn't know anything about your dog's anal glands
before you read this article, you probably know more than you ever
thought possible now! But at least you'll be able to detect and
identify any issues quickly and hopefully save your dog from the
pain and discomfort of anal gland problems.
Who can I contact for further advice?
The Kennel Club is not a veterinary organisation and is unable
to provide general or case specific veterinary advice. If you
have any questions regarding any of the issues discussed in this
article then please contact your local veterinary practice for
This article was written by Marc Abraham and was originally
published in the Crufts Magazine - www.thecruftsmagazine.com.
Marc Abraham is a vet based in Brighton. He regularly
appears on UK television. For more information about Marc
please visit www.marcthevet.com.