Despite reassurances, owners are often disgusted with the habit and may be unwilling to tolerate it. Many persistent coprophagous dogs have been given up for adoption as a direct result of stool-eating behavior. The problem is especially intolerable in situations where a dog comes into close contact with children, who may be licked on the mouth by the dog.
In many species, such as the rabbit, coprophagy (stool eating) is a normal behavior that provides a variety of vital nutrients, including B-complex vitamins. In the case of rats, 5% to 50% of their fecal output is eaten, providing then with an important source of thiamine and vitamin K. Although dogs do not need to eat feces for good health, when they are fed a thiamine-deficient diet, dogs will engage in coprophagy to stave off physical symptoms and attenuate neurological signs of thiamine deficiency, at least temporarily. In horses, foals under 20 weeks of age show a preference for their mother's feces, which they eat. Equine coprophagy may provide foals with various nutrients, such as vitamins and proteins, and beneficial bacterial flora needed for digestion.
Adult males will also ingest feces produced by young puppies. Although dogs of all ages may show this behavior, coprophagy is particularly common among puppies and young dogs between 4 and 9 months of age. Besides eating their own feces, some dogs ingest feces of other dogs and animals, especially cat and horse droppings. Most dogs actively explore the droppings of other dogs and animals, but, for some dogs, something in the feces is sufficiently attractive for them to go further and eat it. The texture and smell of the feces appear to be sufficient factors. Many coprophagous dogs are particularly attracted to frozen stools. Such dogs rarely eat soft or poorly formed stools.
Coprophagy In Puppies
Coprophagy is considered normal among puppies and represents a small health risk to the offending puppy eating its own feces, but eating the feces of other dogs may cause parasitic infections, such as coccidiosis or increase a puppy's risk of coming into contact with viral pathogens shed in the feces.
The exact causes of the habit are unknown, but several ones have been described. There appears to be some connection between excessive coprophagy and nutritional deficiencies, stress, boredom, unsanitary rearing conditions, and restrictive housing. Overly restrictive or isolatory confinement has been linked to a higher incidence of coprophagy in dogs. Dogs kept in kennels or basements are more likely to engage in the habit than dogs kept in close contact with people. Eating non-food materials (pica) has also been reported similarly increased among dogs housed under restrictive conditions, suggesting that both coprophagy and pica may be influenced by environmental stress.
A common assumption holds that coprophagy is related to some sort of nutritional problem or deficiency. The theories generally focus on one of two possibilities: (1) coprophagy is a search for nutrients lacking in a dog's diet or (2) the habit is motivated to consume undigested nutrients passed into the feces. In one study, rapid control of coprophagy was achieved by increasing the ration's protein and fat content, reducing the amount of carbohydrates, and supplementing with brewer's yeast. Another obvious nutritional possibility to consider, and one perhaps more directly linked with a nutritional function, is that coprophagous dogs may simply be harvesting undigested food passed in the feces.
Coprophagy And Enzyme Conservation Theory
Besides undigested food and other nutrients, feces is a rich source of digestive enzymes and bacteria. Whether or not the ingestion of alimentary bacteria is of benefit to dogs is not known, but some evidence suggests that digestive enzymes may play a role in the control of coprophagy. Many veterinarians and dog trainers report anecdotal success when a meat tenderizer containing papain (a proteolytic enzyme) is added to the coprophagous dog's diet. In one study 4 of the 9 dogs treated with a plant-based enzyme supplement responded favorably to the therapy.
After all, although dogs can survive on a vegetarian diet alone, they are preferentially carnivores adapted to eat and digest an omnivorous diet containing a significant proportion of animal protein. Under domestic conditions, dogs are made to eat relatively monotonous diets consisting of high levels of carbohydrates and protein content derived from plant sources. It is reasonable to suspect that some predisposed dogs may exhibit an insufficiency of digestive enzymes needed to digest such food thoroughly, food enzymes that they conserve or harvest by eating their own or other animal's feces. Some dogs appear to have suffered inadvertent physiological alterations as a result of selective breeding, changes that may reduce the production of proteolytic and other enzymes. Dogs are commonly attracted to cat feces, an interest, again, that may be related to harvesting digestive enzymes or partially digested food passed in the feces.
Although the enzyme theory is appealing, some important questions remain unanswered: (1) Most dogs do not develop coprophagy, even when they are on less than ideal diet or starved; (2) Dogs suffering from pancreatic insufficiency (deficiency of digestive enzymes) or malabsorption disorder may exhibit such behavior but only after becoming seriously ill. These questions are enough to regard the enzymes theory with some skepticism, at least until additional research delivers more evidence.
Some breeders and dog owners have reported success with treatment for coprophagy by adding an enzyme product, such as Forbid, to the diet. This product has a bitter tasting amino acid in it that appears in the stool and changes the flavor of the stool to one that does not appeal to the puppy. Another approach is the addition of enzymes that help break down proteins in the stool that may add the attractive flavor. However, these approaches are regarded less effective and successful than giving Albon or Flagyl for five days and practicing good hygiene (cleaning up after your dog in the yard). Some dog owners reported success just practicing this approach.
This kind of behavior in a puppy does not seem to be related to stool eating in adult animals. You need to police the ground where they exercise in order to pick up all animal droppings. Often stools appeal to many dogs when the temperature is below freezing, but they do not appeal to dogs at warmer temperatures.
Coprophagy And Commercial Pet Food
Coprophagy is a relatively common problem in dogs fed commercial pet food, especially dry foods. It is rare in animals fed owner-prepared diets or consuming food caught while hunting. In German Shepherds, coprophagy is associated with feeding high-carbohydrate diets. Coprophagy ceases in working dogs fed horse meat instead of dry dog food, if caloric intake remains unchanged. The problem is managed by feeding owner prepared diets containing sufficient amounts of protein and relatively small amounts of carbohydrates.
Instead of correcting the nutritional problem causing coprophagy, owners often feed pets something to give feces an offensive odor and taste. Chemicals for parasite control are sometimes given orally to discourage coprophagy. Sodium glutamate mixed with a purified edible vegetable protein fraction is marketed with claims for curbing coprophagy. If a pet eats fecal materials of other animals, these preparations have no value.
- Ann Johnson. The Golden Retriever Puppy Handbook
- Donald R. Strombeck. Home-Prepared Dog & Cat Diets: the Healthful Alternative
- Steven R. Lindsay. Handbook of Applied Dog Behavior and Training, Volume Two: Etiology and Assessmen