You've taken your dog for a walk, you've just finished telling the neighbour how well behaved they have been and all of a sudden you catch your dog eating dog poo. Ugh! What could possess dogs to do this?

Coprophagia (the technical term for eating faeces) is unpleasant but not uncommon behaviour among dogs. The good news is that eating faeces won't generally hurt your dog. The bad news you already know; it's disgusting, messy and leads to the worst bad breath imaginable. There's also the risk of acquiring parasites if your dog eats faeces from other animals.

Curiosity

No one is entirely sure why dogs do this but there are a couple of possible reasons. It may simply be that they enjoy it. Dogs interact with the world through their mouths, they like to carry sticks and love to chew on toys or bones.

Dogs also like things that have strong smells and excrement certainly falls into this category. It might seem odd, but eating faeces may just be your dog's way of examining something that interests them

Confused pups

Puppies will sometimes eat their own poo during toilet training. It happens because they're still unsure of where they're supposed to defecate and where they're not supposed to defecate. Afraid they may have done something wrong they will 'destroy the evidence'. This kind of cleaning behaviour can also happen with adult dogs inside the house.