May 20, 2010
Pica: Why Pets Sometimes Eat Strange Objects
Eating non-food items has a name: It's called pica. A specific type of pica is stool eating—either the dog's own or that of another animal—is called coprophagy.
Rarely seen in cats, coprophagy is fairly common in dogs, especially those who tend to be highly food-motivated. And although it's not necessarily dangerous to the animal, it probably is unacceptable to you.
Why animals do this
The causes of pica and coprophagy are not known. Many theories have been proposed by various experts, but none has been proven or disproven. One idea is that such behaviors may be attention-seeking behaviors. If engaging in one of these behaviors results in some type of social interaction between the animal and his owner—even a verbal scolding—then the behavior may be reinforced and occur more frequently.
Others think these behaviors may be attempts to obtain a necessary nutrient lacking in the diet, although no nutritional studies have ever substantiated this idea. Pica and coprophagy may also stem from frustration or anxiety. It's even possible that the behaviors begin as play; as the animal investigates and chews on the objects, she eventually begins to eat or ingest them.
Because pica can be potentially life-threatening, it's advisable to consult both your veterinarian and an animal behavior professional for help.
Some experts have suggested that coprophagy is carried over from the normal parental behavior of ingesting the waste of young offspring. Others believe that coprophagy occurs more often in animals who live in relatively barren environments, are frequently confined to small areas, and/or receive limited attention from their owners. It's also possible that dogs learn this behavior from other dogs.
Because pica and coprophagy are not well understood, stopping these behaviors may require assistance from an animal behavior professional who will work individually with you and your pet.
Suggested solutions for coprophagy
Because the cause of coprophagy isn't known, no techniques or solutions are known to be consistently successful.
However, the following techniques may be effective in resolving the problem:
- Treat your pet's food with something that causes his stool to taste bad. A commercial product called 4-BID™ is available through your veterinarian. The same result may be achieved by using the food additive MSG. Based on owners' reports, both of these products work in many cases, but not always. Before using either of these products, consult with your veterinarian.
- Give your pet's stool a bad taste by sprinkling them directly with cayenne pepper or a commercial product such as Bitter Apple®. For this method to be effective, every stool your pet has access to must be treated so that he learns that eating stool results in something unpleasant. Otherwise, he may discriminate (using scent) which f have been treated and which have not.
- Keep your dog on a leash any time you take him outside. If you see him about to ingest a stool, interrupt him by clapping your hands, spraying a squirt bottle, or shaking a can (only for pets who aren't afraid of loud noises). Then immediately give him a toy to play with instead, and praise him for taking an interest in the toy.
- Clean your yard daily to minimize your pet's opportunity to eat his stool.
- If your dog eats cat feces from the litter box, install a baby-gate in front of the litter box area. Your cat shouldn't have any trouble jumping over it, but your dog likely won't even make the attempt. Or, place the litter box in a closet or room where the door can be wedged slightly open from both sides so that your cat has access but your dog doesn't. Think twice before setting up a some kind of homemade "booby trap" to stop your dog from eating cat feces from a litter box: Remember that if it frightens your dog, it's likely to frighten your cat, too.
Suggested solutions for pica
Pica can be a serious problem because items such as rubber bands, socks, rocks, and string can severely damage or block an animal's intestines. In some instances, the items must be surgically removed. Because pica can be potentially life-threatening, it's advisable to consult both your veterinarian and an animal behavior professional for help.
Here are some other suggestions:
- Make the objects your pet is eating taste unpleasant by applying cayenne pepper, Bitter Apple®, or some other aversive. (For more information on using aversives, see our tip sheets on using aversives to modify your pet's behavior).
- Prevent your pet's access to these items.
- If your pet is food-oriented, change his diet to a low-calorie or high-fiber diet. This may allow him to eat more food, more often, which may decrease the behavior. Check with your veterinarian before changing your pet's diet.
- If you suspect that anxiety or frustration is the reason for your animal's pica habit, change the behavior by using behavior modification techniques.
- If you catch your pet ingesting items and believe it is to get attention, startle your pet with a loud noise or a spray of water. If possible, avoid letting him know that the startling noise or spray came from you, and be sure to praise him when he leaves the items alone. You may want to give him something acceptable to eat or chew. Try to set aside 10–15 minutes twice a day to spend with your pet so that he doesn't need to resort to pica to get your attention.
- If you think your pet's pica habit is play behavior, then keep plenty of toys around for your pet to play with. Cats especially like to play with string, rubber bands, and tinsel, and ultimately ingest them. Keep these items out of reach and provide a selection of appropriate toys. (See our tips on cat toys and dog toys.)
What doesn't work
Interactive punishment (punishment that comes directly from you, such as verbal scolding) is usually not effective because it may be interpreted by your pet as attention. What's more, many animals learn to refrain from the problem behavior when their owner is present, yet still engage in the behavior when their owner is absent.
Punishment after the fact is never helpful. Animals don't understand that they're being punished for something they did hours or even minutes before. This approach won't resolve the problem and is likely to produce either fearful or aggressive responses from your pet.
Adapted from material originally developed by applied animal behaviorists at the Dumb Friends League, Denver, Colorado. All rights reserved.