In the past it was believed that faeces eating, also known as coprophagia, was caused by either poor diet or poor health. However, this theory is not supported by current research. "Behavioral research has discounted the idea that it is a dietary deficiency or a pancreatic enzyme deficiency," says Dr. Jo Ann Eurell, a veterinarian and animal behavior specialist at the University of Illinois College of Veterinary Medicine. "Dogs are historically scavengers, and this is believed to be a scavenger behavior.

"It is important for dog owners to know that this behavior is normal for a mother dog with pups," adds Dr. Eurell. Newborn pups must learn to urinate and defaecate. The mother teaches the pups by licking their bottoms. The pups respond to this "tickle" by urinating and defaecating.

The mother then consumes the pups' excrement, which serves two protective purposes: it keeps the den area clean and it removes smells that could attract a predator. Some pups learn this behavior from their mothers and will stimulate themselves and consume their own faeces. Most pups stop by the time they are weaned.

It is more difficult to understand why adult dogs eat faeces. Some dogs will learn this behavior from other dogs. In some cases, eating faeces may be an attention-seeking behavior. For some dogs it is possibly due to anxiety or boredom. Most often the motivation for eating faeces is just not known.

Owners find this habit in their pet disgusting -- particularly when the consumed faeces are thrown up all over the new carpet. In addition to being socially unacceptable, eating faeces exposes the dog to parasites and diseases. So, what is a dog owner to do?

"Eating faeces is a problem that is easier to prevent than to cure," says Dr. Eurell.
"Don't allow the opportunity to arise. Keep the dog's yard clean by disposing of feces promptly. Move the cat box out of the dog's reach. If cleaning the outdoor area is not feasible, then keep the dog on a leash or use a muzzle when outside."

There are some "cures" that have been used with limited success. Punishment generally only works in the early stages, before the behavior becomes habitual.
Feeding the dog MSG, garlic, or pumpkin is believed to give faeces a bad taste, making it less attractive to the dog. Other products can be applied to the faeces directly; however, dogs are very perceptive and can probably distinguish between tainted and untainted faeces.