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Why Do Dogs Eat Poop?

4 min read

Veterinarians commonly deal with owner complaints that their dog eats its own or another animal’s feces or poop. Although there is much speculation why dogs indulge in this behavior, we still don’t know exactly why some dogs have this disgusting habit.


Many Animals, and Humans, Eat Feces


Coprophagia (cop-row-fage-ee-uh) is a Greek word meaning feces eating and is used to describe this behavior. We all know of feces eating insects, but many more animals are in this group. Rations on pig farms used to be formulated to account for a certain percentage of coprophagia. Rabbits and hamsters and other cecal or hindgut digesters routinely eat their feces in order to extract more nutrients from their food that may have escaped fermentation the first time.


Elephants, pandas, koalas and hippo young are born with sterile intestines. They eat the feces of their mother in order to seed their intestines with the bacteria needed to aid in the digestion of local vegetation. Female dogs and cats stimulate urination and defecation of their new litters by licking the rectal, vaginal, and penile areas of their young. Dutifully, they eat the feces and drink the urine to avoid contamination of the nesting area.


Gorillas and chimpanzees have been observed eating feces. The behavior is believed to enhance the extraction of nutrients from the tough seeds in their diet. Coprophagia has also been reported in some human patients with schizophrenia, depression, or pica (eating non-food items).   


The Medicinal Use of Feces


Clostridium difficile of C. diff infections in humans are reported to top 3 million per year and account for approximately 110,000 deaths annually in the U.S. Early treatment of the condition is fecal transplantation. Patient are fed their own “banked” feces, or that of a close relative, through a feeding tube, or purified bacteria from the same fecal sources, which are put in gelatin capsules. The “good bacteria” from the feces crowds out the C. diff in the intestines and results in a quicker treatment response. Fecal enemas have proven to have the same beneficial effect.


Prebiotic, or “good bacteria,” are also used in veterinary medicine to aid in the treatment of diarrhea in dogs and cats. The leading veterinary brand of prebiotic lists its first active ingredient as “ingesta.” Ingesta are intestinal contents, more commonly known as poop.


What are the Reasons for Coprophagia in Dogs?


The most common reason cited for dog coprophagia is nutritional deficiency. The lack of iron, or other minerals or vitamins lead the list. But there are no studies to confirm nutritional deficiencies as a cause for coprophagia.


Hunger or near starvation is also suggested as a reason for coprophagia. This view is enhanced by the observation of emaciated wild dogs and canids eating feces. Again, there are no studies to substantiate that hungry dogs are more likely to eat feces than well fed dogs.


Others suggest that like the animals that eat feces for specific nutritional needs, as mentioned above, healthy dogs benefit in the same way. One could argue that they are replenishing their “good gut bacteria” this way. If this were true, then all or most dogs would eat feces. In fact poop eaters are in the minority in veterinary practice. Although fresh feces might contain food residue and beneficial bacteria, old, dried out feces lacks these benefits.


Coprophagia Should Be Discouraged


Your dog’s coprophagia could pose a threat to human household members. Dogs can harbor bacteria like Salmonella, E. coli and infectious parasites in their gut without any signs of illness. These organisms can easily be spread to household members that allow their dogs to kiss their faces and lips. Remember a dog’s tongue is its toilet paper!


The addition of MSG (monosodium glutamate) or MSG containing products (meat tenderizers) to the diet of the animal whose feces is being eaten often helps discourage coprophagia. In multi-pet households, it is probably easier to add MSG to everyone’s diet. Cats may not readily eat MSG-laced food, so if your dog eats cat poop, you may have to be more strategic with the litter box.


Your veterinarian can help you with the proper dose of MSG.


Dr. Ken Tudor


You may also be interested in reading:

What to Do When a Dog Eats Poop

Nutrition Gone Bad – Dogs That Eat Cat Poop

Why Do Puppies Eat Poop?

Coprophagia and How it Relates to Digestive Enzyme Deficiency in Dogs