How to tell if your dog's poo is healthy

The colour of dog poo is determined by two main factors: the diet and the dog’s health. Your dog’s poop will be individual to them, so you’ll come to know what is normal in colour, consistency, shape and frequency. 

For most dogs, the colour of their poop will be somewhere between a mid- and chocolatey-brown. If they’re being fed a white meat- or fish-based diet, their poo will be lighter, and if their food contains colouring, this may show in their poop. Dogs who are fed a varied diet might have slightly different poop on any given day.

When your dog’s digestive system is working normally, they’ll produce little ‘logs’ of poop. Pebble-like poo might mean your dog hasn’t been drinking enough, while long ‘sausages’ are sometimes produced when the poop is a bit soft. 

When you pick up after your dog, their poos should maintain their shape and should be easy to collect. Once in the bag, they should be squidgy enough for your finger to make an indentation in them. If it’s difficult to separate your dog’s poop from the grass in the park, it’s probably too loose.

The size of the poops your dog produces will reflect how much indigestible material, i.e. fibre, they have eaten. This will be individual to your dog and there will be a little variation, depending on what they’ve eaten. If they’ve had extra food, they could produce a particularly large amount in one go. On the other hand, if they’ve been running around excitedly and have passed more than one lot of poop during the same walk, they might just produce a small volume. The size of the actual logs shouldn’t vary much though. 

Of course, dog poop always smells! But you’ll become familiar with what’s normal for your dog. The smell of your dog’s poop usually depends on their diet but if they aren’t feeling 100%, it might affect the smell, as well as the appearance of their poop. A sudden change to really stinky poop could mean that your dog has eaten something that doesn’t agree with them, or that they’ve picked up a bug.

Black dog poop could be a sign that your dog has digested some blood. This could happen if they’ve swallowed blood, for instance, following an injury to their mouth or throat. Much more commonly though, the blood has come from the upper digestive tract – the stomach in particular. Some medicines can make a dog more likely to develop gastric ulceration or bleeding.

When blood is digested, it becomes black and this shows up in the dog’s poop. If your dog’s poop ever looks blackish, or shiny and tar-like, contact your vet team urgently to get your dog checked out. Never give your dog medicines designed for humans unless your vet has prescribed them and has explained exactly when and how to use them. If your dog ever helps themselves to any medicine at home, such as aspirin or ibuprofen, they will need immediate veterinary care.

Dog poo that looks red, purple or pinkish could contain fresh (undigested) blood. Fresh blood in dog poo suggests bleeding somewhere in the digestive tract other than the stomach. Infection and inflammation in the digestive system, and even tiny tears or scratches in the lining of the rectum or the anus, can lead to small haemorrhages showing as a dot or swirl of blood at the end of a poo.

Significant bleeds, where a dog seems to pass a puddle of liquid or clotted blood, sometimes resembling jam, are more serious. Any suspected bleeding in your dog’s poo should be checked out as soon as possible – profuse bleeding or blood clots from the digestive tract should be treated as seriously as heavy bleeding from anywhere else on the body. 

Blue dog poo only occurs when dogs have eaten something containing blue colouring. If your dog has eaten someone’s birthday cake with food colouring, you probably have nothing to worry about. However, rodenticide is often dyed bright blue. If your dog has been out of sight, away from your own garden, there’s a chance they could have had access to rodenticide. Contact your vet as an emergency, even if your dog seems well. 

Orange dog poop can be a sign that your dog’s gall bladder isn’t squirting enough bile from the liver into the intestine. Bile is what gives your dog’s poo its usual brownish colour so, if something interferes with bile production or secretion, the poop won’t be as brown as it should be. Reach out to your vet team to get this investigated and remember to take in a sample.

Loose or yellow dog poo sometimes appears because the digested food has moved through the intestines so quickly that bile hasn’t had time to be mixed in properly and turn it brown. This can be a sign that your dog has eaten something that doesn’t agree with them – for instance, a new food, or something to which they have an intolerance. If you know your dog ate something new or unusual, you could try returning to their usual food but if your dog’s yellow poop carries on, take your dog to see their vet, along with a sample.

Greasy or grey dog poo suggests that oils and fats could be passing undigested through your dog’s digestive system. The pancreas should secrete enzymes into the intestine, breaking down fats and oils so they can be absorbed by your dog's stomach. If there’s a problem with the pancreas, the fats come out in the poop, which might also look runny. If this only happens once, and you know your dog was given some fatty leftovers from a roast perhaps, you can monitor them provided they seem well. If the poop still looks unusual or if your dog seems at all off colour, contact your vet.