puppy showing his bum and the position of anal glands in dogsToo Many Soft Poo’s is the Cause of Anal Gland Issues in Dogs…

Anal gland issues are almost entirely a dry-fed dog phenomenon. The anal glands, situated at 4 and 8 o’clock around the dog’s anus, are like two tiny nipples. Their function is to release pheromones on to the stool, to enable communication between dogs . This is why dog’s sniff each other’s butts. As faeces passes over the anal glands they are expressed, this causes the pheromones to be released.

However, if the faeces is too soft, these will not be expressed. Over time, this results in a build up of the anal glands, which can then become impacted. This is very sore for a dog and materialises by them dragging their bum along the ground in an effort to express them.

When this does not work, they require manual expression by the dogs owner or a vet (see below, pretty graphic, best leave it to a groomer or vet as the stuff absolutely stinks). If left unattended they will build up and impact, causing severe pain, even rupturing, so they need to be attended to.

Soft faeces is the cause of a dog’s anal glands issues. It is most likely the dog is dry fed (as he has anal gland issues) as pelleted dry food increases the water content of stools (Stroucken et al. 1996). The question is why? There are two reasons – the first is the presence of too much indigestible plant fibre in the dry food and the second is food sensitivity.

To Understand Anal Glands in Dogs First You Need To Understand What Poo Is!…

Faeces (or stool) is the undigested leftover bits from food that has passed through the digestive system. A meal that is high in indigestible food will lead to larger waste material (i.e faeces).

If you eat a very digestible meal (like pasta) or chicken breast, it will produce very little waste as the body will digest and assimilate almost everything that went in. On the other hand if you eat a meal full of less digestible material (like plant fibre) then more will make it out the other end.

This affect is magnified for carnivores. Plant fibre requires a long, slow digestive system with special gut micro-flora that is adapted to breaking it down, such as that of a cow. We omnivores with our shorter and relatively faster digestive systems, are a little worse at it. We have systems that need to accomodate a bit of meat and less fibrous additions.

Dogs and cats are carnivores. Left to their own devices they consume a diet of 97% animal protein. They have short, fast guts with stomach acids like battery acid, around pH1.5. They are designed to digest meat which by it’s nature is a very digestible food stuff, void of all the indigestible fibre you get with plant material. Due to this, a dog generally has significantly smaller stool’s than an omnivore who in turn have smaller poo’s than a herbivore!

What Does the Ideal dog Stool Look Like?

A good dog stool is reasonably small logs or nuggets, roughly the size of a large thumb., though they will vary in size between breeds. As they do not contain much fibre, they are firmer and not as moist as human faeces. They should be relatively firm and easy to pick up, leaving a slight residue.

The Role Of Insoluble Fibre in Soft Poo’s…

Fibre moderates the speed that food passes through the digestive system. Indigestible plant fibre acts like a sponge in the stool, absorbing water from the surroundings. This has a bulking effect, making the stool wetter and softer, lubricating the stool and speeding up it’s arrival out the other end.

While the dog’s system is ideal for digesting meat it is really poor at digesting plant material. It doesn’t hold on to it long enough for digestion to occur. Even if it did they don’t house the necessary microbes to get the job done. And they don’t have the enzymes. And their teeth don’t grind down the rough plant material at point of entry.

The only fibre your dog really needs is that he sources from the hair or feathers on his prey, maybe some nails, maybe some leaves that stuck to his meal, maybe a bit of grass that they sometimes like to eat. They don’t need plant material. Lots of people (me included) use some plant additions (such as greens) in their dog’s diet to aid the flow of digesta through the gut as in general few of us are feeding whole animals with hair and feathers. The bif of plant fibre here is an attempt to replace that.

With this in mind, the addition of plant fibre to your dog’s diet will make his poo’s softer. If you are feeding a dry food that is high in crude fibre it may play a role in making his stool too soft. S

The Role of Food Intolerance in Soft Dog Poo’s…

The second cause of dog’s anal gland issues is food intolerance, most likely to wheat (gluten) and cooked protein. As highlighted in our popular Allergy in Dogs articles, the majority of dogs are suspected to be intolerant to wheat gluten. This means they can not digest it and their immune system around their guts becomes effected.

This causes inflammation of the gut and the body trying to get rid of the problem as quickly as possible through the back door. This digesta is not well formed and is often soft to the point of being diarrhoea.

The Cure to Anal Gland Issues in Dogs

The cure is two fold. Firstly, the dog should not be fed any stool-loosening foods (indigestible plant fibre, wheat gluten, cooked protein, in other words dry-food and pet store treats like dental sticks). Remove all these and feed a biologically appropriate fresh dog food.

Once the bad stuff is removed and the good stuff is put in the dogs stools will dry up a bit, becoming firmer and the dog should be able to express the anal glands normally.

In the mean time, and certainly for those staying on dry food, maybe think about adding some fibre to firm up his poo. Some vets recommend a “handful of muesli” for that bit of fibre. However muesli is rarely gluten free so careful here. I recommend StoolRite to produce a firmer stool.


Stroucken, W. P., van der Poel, A.F., Kappert, H. J. and Beynen, A.C. (1996). Extruding vs Pelleting of a Feed Mixture Lowers Apparent Nitrogen Digestibility in Dogs. Journal of the Science of Food and Agriculture, 71(4): 520–522