I have a mare that will be four years old in May. I bought her as a yearling. She is energetic and healthy, and her manure is essentially normal, but she passes gas constantly and "squirts" small amounts of diarrhea with the gas. It is worse when she's in heat. The vet says it's a stress reaction to being in heat. She is not at all "marish" when in heat, in fact, were it not for this, you could never tell! Her tail and hind legs have dried diarrhea on them constantly! I have tried giving her probiotics, "For-a-Flex" and "Probios". Not really any help. I wonder if a "mare" supplement might help. Has anyone had this experience?