I know when my dog had that happen to her I took her to the vet to make sure she was alright and the vet sent the stool sample out. Told me to put her on a bland diet and I would know the next day what the sample says. The next day she said there wasn't anything wrong with her stool sample and that we could just chalk it up to a digestive indiscretion. A couple of days later her stool was normal. She never acted sick either.