In the wonderful James Herriot novels, Mrs Pumphrey has a Pekingese called Tricky Woo. One of Tricky Woo’s recurring issues is a condition his owner refers to as “flopbot” – essentially, rubbing his bottom constantly along the ground.

Some pet owners worry this is a sign of worms, but far more often the itchy bottom is actually caused by an impaction of the two scent glands (or sacs) that are located between the inner and outer muscles of the bottom. The scent glands are located there so that as the dog or cat passes a motion, the two glands are squashed and a deposit of liquid from the glands ends up on the faeces, essentially marking their territory (when dogs are sniffing each other’s back ends this is actually what they are trying to smell).

The liquid in these scent glands is foul smelling and it is the same substance that the skunk has evolved to fire out as a defence mechanism! In fact, many carnivores have these scent glands including bears, hyenas, wolves and, of course, cats and dogs. Most of the time this process occurs unconsciously, but if the glands have become full, it can cause discomfort, hence the rubbing of the bottom. They can even spontaneously empty, which can leave this unpleasant liquid deposited in an entirely unsuitable location!

Surgical gland removal is possible

The glands can also become infected, which can result in abscess formation and significant discomfort. It can occasionally be a location for cancer formation (spaniels being particularly prone to this). I recently had a patient that needed my surgical help. A Westie had had recurring abscesses that had caused significant pain and damage to the tissue in the area. The dog required surgical removal of the anal sacs. As the glands don’t perform any function other than as a scent marker, removing them is not really a problem, other than the area itself is extremely delicate and the muscles of the bottom are critical for maintaining bowel continence.

Fortunately, the operation went very well and the Westie was almost immediately far more comfortable. The owner reported that she was a much happier dog after the procedure (and probably very grateful to not have to have her glands manually emptied anymore).

Emptying anal glands is not high on the list of pleasant parts of being a vet, but it has to be done fairly commonly. So, if your dog or cat is showing persistent signs of ‘flopbot’, get them checked by your local vet!