Poop eating. Lots of dogs do it.
Many are quite proud of it.
Owners? Generally not so enthusiastic.
What do they eat? The technical term for poop-eating, of any type, is coprophagy. Many dogs readily consume the feces of other animal species – rabbit, deer, horse, possum and raccoon. Additionally, dogs who share their home with a cat often find poop of the feline variety to be especially tasty.
Lucky for us all, a smaller proportion of dogs consume the excrement of other dogs (called conspecific coprophagy). It is these dogs that we are looking at today.
Yes, this is an intervention. It is time.
Believe it or not, there is some science on this topic – a few actual studies, even. Let’s review what we currently know about the dogs who eat canine feces, why they may do this, and how to best prevent or manage this unsavory behavior.
Lots of dogs do it…..
Coprophagy is considered to be a normal behavior in mother dogs. For the first several weeks after her pups are born, the mother ingests all of her pups’ feces. She does this for hygiene purposes to keep her puppies and the whelping area clean, and also because the associated licking and cleaning of the puppy provides needed stimulation for elimination. Mothers typically stop this after 2 to 3 weeks, once the puppies are starting to walk and can urinate and defecate without aid.
Stool eating is also relatively common in other adult dogs. A recently published survey study asked dog owners a series of questions regarding conspecific coprophagy (1). The researchers received almost 1500 responses. (Clearly, this was something dog owners wanted to get off of their chests). The results showed that between 16 and 23% of dogs either occasionally or frequently consumed the feces of other dogs. The dogs who showed frequent coprophagy were more likely to live in multiple dog homes than dogs who did not coprophagize (more about this in a bit).
Results also showed that in addition to being a commonly reported behavior, the majority of poop-eating dogs (82 %) directed their attention to poops that were fresh – no more than two days old. Add that to the yuck factor for owners.
For the researchers however, this fact was a significant one. Most intestinal parasites need to remain in the environment for several days or longer before becoming infective. This fact suggests that coprophagy has been selected for during the dog’s evolutionary history. Rapid consumption of recently voided feces would reduce the risk of infection with intestinal parasites. The researchers suggested that this tendency provides support for the “poop eating is a normal dog behavior” theory.
Finally, evidence from this study dispelled several prevalent poop-eating myths. Coprophagy was not associated with a dog’s sex, neuter status or age. Nor were early weaning, late or difficult housetraining, or compulsive-like behavior problems associated with a dog’s chance of developing a poop eating habit. Finally, this study, and others, dispelled one of the most prevalent myths about poop eating – a dog’s diet.
Diet and Poop Eating
Despite the many diet/nutrient-related beliefs about poop-eating in dogs, there is no scientific evidence that suggests dogs consume feces because of a particular nutrient deficiency or because they are fed a specific type of food.
So, when Joe Next Door (who happens to know a lot about dog poop) tells you that your dog consumes poop because: (a) you feed a certain brand of dog food; (b) you feed a food with too much carbohydrate; (c) you feed a food with too little carbohydrate; or (d) your dog is expressing a deficiency in [pick a nutrient that Joe can pronounce], feel free to tell Joe that he is full of…… dog poop. No studies to date have found an association between dogs’ diets and their propensity to develop coprophagy. Sorry Joe.
There is one diet-related behavior that correlates with coprophagy, however. Dogs who are reportedly “greedy” or rapid eaters are more likely to also enjoy eating feces. This observation suggests that dogs who experience higher levels of hunger may be more inclined to coprophagize. However, a pair of studies that followed the behavior of a group of dogs that initially had food available at all times and were switched to restricted meal feeding reported no difference in stool eating when the dogs were fed less food (2,3). This suggests that hunger may not be an underlying cause of the greedy eater connection.
Wait. You can eat that??
As noted above, the survey study found that dogs who frequently consume the feces of other dogs are more likely to live in a multiple dog home. Of course, this might simply reflect increased opportunity (i.e. more poop = more poop eating). A second set of researchers took a deeper look at this connection. They conducted in person and written interviews with the owners of 70 dogs; 30 dogs were identified as conspecific coprophagizers and 40 dogs refrained from eating feces.
Similar to the larger survey study, no associations were found between coprophagy and a dog’s sex, reproductive status, living situation or type or diet. However, poop eating was significantly more likely in homes that not only had another dog, but had another dog who also engaged in coprophagy. This should really not be surprising, given what we now understand about observational learning in dogs (they are very good at it). Dogs not only follow the attention of other dogs and will investigate items their friends are interested in, they also are capable of learning new behaviors from each other through observation (see “Doggy See, Doggy Do?). So, coprophagy may be learned from housemates. (Friends don’t let friends poop eat alone).
On a personal level, I rather suspected this. Our very first Golden, Fauna, was an intermittent poop eater. She apparently introduced this habit to one of her younger sisters, Roxie. Roxie then passed it along to Sparks, who gladly handed the torch over to Gusto, who mentored Cadie…….and onward. Today, we have Alice, who offers tutoring services to anyone who is interested. Lucky for us, neither Cooper nor Stanley have apparently yet taken her up on this generous offer.
It is now clear that a substantial number of healthy adult dogs indulge in the occasional poop treat. The general consensus is that coprophagy is a normal canine behavior, not an aberration. Its functional history is probably related to hygiene, parasite prevention, and possibly to scavenging behavior. This does not mean that owners of poop-eaters must accept this or allow it to continue. Rather, it means that there are probably no underlying health or behavioral issues in dogs who coprophagize and that it should be treated as a normal canine behavior that can be modified through management (mostly) and behavior modification (somewhat).
Before we look at what can help, let’s review what the science currently tells us doe NOT work.
- Commercial supplements: There are a lot of these. They contain a lot of things. Some claim to either change the taste of feces, making it unpleasant to consume or to alter fecal odor. Others profess to contain nutrients that are lacking in the dog’s diet and that, once provided will magically stop the poop-eating. None provide controlled studies demonstrating efficacy. Owners who try these products report a reduction in poop-eating in less than 2 percent of cases. Save your pennies.
- Reducing carbs: This is a popular one. Although an early study suggested that a high carbohydrate diet may increase a dog’s tendency to eat stools, there is no research evidence to date showing that reducing carbohydrate in a food reduces coprophagy in dogs. Yeesh. Carbs get blamed for everything these days.
- Reducing boredom: Well, this is always a good thing to do, of course. Increasing play, exercise, and opportunities for owner interactions are all good things for our dogs. However, the only data that are available show that providing different types of toys to kenneled dogs as an attempt to relieve boredom did not reduce coprophagy. (But really, do all of this stuff with your dog anyway).
- Punishment: In the large survey study, some owners used an electronic collar or other aversive in an attempt to punish coprophagy. Similar to the use of supplements, attempting to punish coprophagy had an abysmal success rate – less than 2 %. Please, do not do this. It does not work and it is not a nice thing to do to your dog.
Take Away for Dog Folks
There are several important points to take away from these recent reseach studies and the evidence that they provide:
- Coprophagy is a normal dog behavior, exhibited by many healthy adult dogs, in different living situations that are fed a wide variety of foods. Some dogs eat poop. We need to accept this and move on.
- Dogs pay attention to what their friends are eating. If you have a dog who eats poop, it is likely you will have more. Sorry.
- Poop eating is resistant to change. Diet supplements do not work. Punishment does not work and is a bad thing to do anyway.
- What can you do? Pick up your yard frequently. Supervise your dog. Reduce or completely prevent access to feces. Train a solid “Leave it” response using reward-based methods. This means that your dog learns that you consistently have a yummy treat that is much more attractive to her than the poop she is considering consuming (com’on now, its not a high bar to clear).
- Enjoy your dog. Spend time, have fun together. Train that “Leave it” and chill a bit. Yeah, he might eat poop. But then, you probably do a few things that your dog finds annoying too.
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- Hart B, Hart L, Thigpen AP, Tran A, Bain M. The paradox of canine conspecific coprophagy. Veterinary Medicine and Science 2018; 4:106-114.
- Crowell-Davis SL, Barry K, Ballam JM, Laflamme DP. The effect of caloric restriction on the behavior of pen-housed dogs: Transition from unrestricted to restricted diet. Applied Animal Behavior Science 1995; 43:27-41.
- Crowell-Davis SL, Barry K, Ballam JM, Laflamme DP. The effect of caloric restriction on the behavior of pen-housed dogs: Transition from restriction to maintenance diets and long-term effects. Applied Animal Behavior Science 1995; 43:43-61.
- Amaral AR, Porsani MY, Martins PO, Teixeira FA, et al. Canine coprophagic behavior is influenced by coprophagic cohabitant. Journal of Veterinary Behavior 2018; 28:35-39.