It’s not often that a photograph motivates a topic for the blog, but when friend and colleague Melissa McCue-McGrath sent me this image of her dog Captain, along with a suggestion to write a post on pica, how could I resist? In spite of the amusing photo (no, Captain didn’t really drink any booze), pica can be a serious problem. I saw one dog who lived by a rocky outcropping, and ate rocks compulsively. The vet had already done three surgeries to remove them, and said there was too much scar tissue to attempt another.
Pica refers to the ingestion of non-food items, often with an assumed compulsive component to it. This isn’t too difficult to diagnose in people, but gets a bit trickier in dogs. Animals whose name in Navajo is “eater of horse poop” can hardly be diagnosed with a serious behavioral or medical problem if they inherently define much of the world as food, including sunflower seed shells, cat poop and vomit. But there are a lot of substances that dogs can become fixated on that can cause them harm. (Also true for cats–see wool sucking.) Rocks are one example, as is metal, plastic, and cloth. Dogs have also been known to eat marbles, pencils, linoleum, jewelry and, of course, underwear.
However, eating feces (coprophagia) is not considered by most to be an example of pica, no doubt in acknowledgement that most dogs love the stuff, sometimes including their own, and that is often might have some food value in it. On the other hand, I couldn’t find any references that included grass eating as pica, although clearly it’s not food, at least to a dog. Perhaps it is so common that no one wants to categorize as “abnormal”? (But see below for a discussion of why we might include grass eating as an example of pica.) The definition of pica might be a bit fuzzy, but it usually refers both to the item (is it dangerous for the dog or beyond anyone’s definition of food?) and/or to whether the individual behaves as if it were a compulsion, and seeks non-food items out c0mpulsively. Thus you can see that diagnosing pica is a bit squishy, but if a dog has a belly full of plastic because she will move heaven and earth to ingest it, it clearly needs to be addressed.
Causes of Pica? All the answers I’ve seen are some version of “throw every possibility against the wall and see if it will stick”. Here’s what Best Friends, for example, has to say about it: “The causes of pica can be hard to determine, but can include gastrointestinal disease, anemia, liver disease, pancreatic disease, diseases causing excess appetite (such as diabetes), neurologic diseases, poor diet, being on medications such as prednisone, behavioral disorders such as anxiety, or a depraved home environment. Pica can even be a symptom of normal exploratory behavior.”
I’m tempted to add in “sibling rivalry, or being forced to wear pink collars if you’re a male dog”, but the fact is that there seem to be a multitude of reasons why a dog might become obsessed with eating weird stuff. Or at least, stuff we think is weird. (Rotten fish excluded. Dogs clearly think this food is manna to the gods.) We simply often have no idea why dogs become crazed about ingesting pencils, or rocks, or My Pony dolls. We do know that pica in humans is more common in children with developmental disabilities, but that doesn’t help us much with dogs. s
Once you’ve decided you are dealing with pica (remember that the item has to be ingested versus just chewed), then it’s time to look at your alternatives.
FIND THE CAUSE IF YOU CAN: Since some pica seems to be caused by medical problems or a nutritional deficit, I’d start there. My Maggie eats grass, but much more often if I don’t give her a supplement of dried herbs. She gets a good varied diet, but that doesn’t mean she isn’t craving something that her body might be missing. There is some suggestion that individuals might be lacking vital minerals, or even might have ingested toxic substances that they are trying to buffer. If your dog wants to eat a type of plant or substances with minerals, you might want to investigate this potential. This, by the way, is why I wonder if compulsive grass eating might be considered a kind of pica. Just because it is common doesn’t mean it’s an issue. However, canids in the wild are known to eat the stomach contents of ruminants, so perhaps it’s not out of bounds to call grass “dog food”.
Stress is another factor that might motivate pica. Maggie the grass eater, for example, often eats grass after a difficult training session. I don’t worry about it, because, well, it’s just grass, but I do make a mental note that whatever we were working on was stressful for Maggie. Sometimes it’s blindingly obvious, like when an older, sassy ewe challenges her, but other times I would have had no idea that she found the work stressful. In that case there is actually a benefit to her behavior.
But of course, if she was eating large rocks or weird plastic things it would be a big problem. Which brings us to the next alternative.
MANAGE: Even if you’ve found a cause, you are probably still going to need to manage the issue, at least for awhile. Traditionally, owners are advised to prevent the dog from having access to the item it is eating. This can be a lot easier said than done. In the case of the rock-eater I told you about earlier, it wasn’t easy at all. While we pursued questions about the dog’s health and nutrition, we simply had to keep him from eating rocks. And there were rocks literally everywhere. The dogs also was used to being outside, off leash and alone for long periods of time. Eeeps.
To make matters worse, the dog would panic if left inside alone. If outside on leash the dog would lunge for rocks and swallow faster than the owner could stop him. I also knew that the owner had a limited amount of energy and patience for radical changes, even though he clearly adored the dog and wanted to keep him safe. And so we focused on conditioning the dog to a basket muzzle that he always wore when he was outside. This wasn’t a perfect solution, but a practical one that did indeed prevent the dog from eating rocks. (Although I warned the owner that he needed to fit the muzzle carefully, or his very smart and determined Labrador would have it off in a matter of minutes.)
One good way to managing this issue is to teach the dog “Leave It” (See Family Dog Training). Of course, it has its downsides–the owner has to want to train it in a step-by-step fashion and 100% might be unrealistic. Ifs the dog was too motivated for the reinforcement, or the owner didn’t see the object before the dog eats it, it’s not going to work. But it’s not all that hard to train and can work incredibly well, especially if the object in question isn’t dangerous. I use it all the time at the farm (dead rabbits, dead mice, dead anything for that matter) and although I’ve been a bit lazy lately with reinforcements (note to self), it works 99% of the time.
Another and even better way to manage pica is to use the object itself as a cue to get something better. This only works if the dog is focused on only one type of object, but it’s a favorite because it takes the owner out of the picture and teaches the dog to make the decision herself. That’s the beauty of this kind of operant conditioning, in which the dog learns that if she seeks socks (for example), she’s going to get chicken if she turns around and goes back into the kitchen. If you know the basics of training, and if the object is consistently identifiable, and IF the dog is not so compulsive it has no control over itself, this is the way to go. I know, lots of ifs… but if possible, it’s a great thing to try.
All that is required is letting the dog see the object (without being able to get it), using a cue like “no socks!” and reinforcing the dog for turning away. I’d help the dog by luring it first, but drop it out as soon as I can. Once the dog turns away to “no socks”, I’d repeat the exercise several times in a row, drop out the verbal cue on the 4th or 5th repetition, and wait for the dog to anticipate you saying it and turn all by herself. If that happens, Whoo hoo! Best reinforcements ever for doing it on your own! If not, just go back to saying the cue, and try dropping it out later. This is all easy enough to describe, but if you are not a professional trainer, or well-versed in operant conditioning, I’d bring in a coach for a few sessions. Coaches are great, right? What professional athlete would be without one?
One last thing before I turn it over to you and your experience with pica. Please, please don’t correct the dog. If the dog’s behavior is truly compulsive, then corrections are just going to make it worse. We all know how fast a coprophagic dog can gulp down feces if she’s been corrected for it–it just makes her more determined to swallow before you can stop her.
So… now it’s to you. Have you had experience with pica? (I initially meant with your dog, but since it happens in children especially, we’d all learn a lot if you’d share any experience you’ve had no matter the species.) I’m especially interested what has worked for you, or not worked, if you’ve had to deal with this issue.
By the way, the rock-crazed Labrador was doing very well for a few weeks, but then I lost touch with the owner and I can’t tell you how it went long term. I have to admit I was always a bit worried. Hope you’ve never had to deal with it or had a positive experience.
MEANWHILE, back on the farm: I can’t write much because I’ve got 4 talks in 3 days to finalize and I’m running out of time. This Thursday I’m giving the Anne Lydecker Lecture at UW River Falls at 5 pm on campus. Friday I speak to two high school classes in Eau Claire, then speak on Saturday at the Chippewa Book Festival. I get home Saturday night and then spend Sunday at a sheepdog training clinic. I can work Maggie now for very brief periods of time (yay!), but I’m taking Willie too so that he can help me learn to shed (seperately one to two sheep off from the group).
Here’s some great news! There is some sun today, warm, gorgeous, beautiful sun. After the continual deluge that we’ve had for literally most of the summer, and never ending clouds, a little sun goes a long way. We’ve had so much rain, by the way, that everyone’s sheep are fat. Seriously. They actually jiggle when they walk. Our Cupcake ewe has always been, uh, robust, but now I describe her as having icing on top.
The dogs have been enjoying the sun too. Every one of them has been lying in a patch of sun as I write this:
Hope there’s some sun in your life too.