Q: I have a 9-week old miniature schnauzer. We are working on training her to go to the bathroom outside. Today, she wanted to eat her own feces. Why? I barely had a chance to praise her for going outside or clean up the mess outside. I am confused. Can you share some insight here?
A: Eating feces seems to stem from instinct in dogs, and is an extremely common behavior. I've heard that it's more common in females than in males, and that makes sense, because the mother dog typically eats the feces of her puppies until they stop nursing. But it's very common in male dogs, too. And show me a dog who won't eat cat poop, if given the chance! There aren't many!
There's a good chance of getting it stopped if you consistently pick up the stool before the dog has a chance to eat it. Don't scold her or make a big deal out of the behavior. She would never understand your objection!
Use a word for "Outside" as you take her out the door, and another word/phrase for "Go potty" when she is in the right place to do it. Then when she does relieve herself outside, you can praise her by saying "Good girl to go potty outside!"
Sometimes you might want to give her a treat after you say this praise. Do not let her see the treat until this point. It's a reward, not a bribe, plus you don't want her distracted from relieving herself by watching your hand waving around with a treat in it. Pulling out a treat at this moment could also nicely distract her from trying to eat the poop.
At her age, she could have worms, so be in touch with your veterinarian to make sure that is all under control. Worms in the stool can encourage this habit. Also, feed her 3 or 4 times a day (you can cut it to twice a day as she gets older), rather than just leaving food out for her in a dish all the time. That helps get a dog to eat on a schedule, which is better for her physically in multiple ways, and aids in housetraining, too.
If you pick the stool up before the dog can eat it, eventually the habit seems to fade. This behavior is not the least bit unusual, and doesn't mean anything bad about your puppy.