I have an 18-year-old QH/TB/Morgan mare who has been struggling with intermittent liquid in her poop for a couple of months. She is in light work, is an average keeper, is otherwise happy and healthy except her tailbed seems dry. She is on pasture with a herd of about 15 (but we're in California so it's dry now and they get grass hay twice a day). Some recent history: I had both horses at a different facility also on pasture until the beginning of July. The barn owner switched hay to absolute crap in June, which is when the runny poops started in several horses there, including both of mine. I complained, barn owner was defensive and refused to fix situation, etc, so I immediately pulled them out of there. Hay is MUCH better at the new place and they have a year's worth in the barn. My other horse's manure improved to normal within 2-3 days and she is doing great. But this horse hasn't quite bounced back. Her actual manure looks much more formed (but still not quite normal) but she's definitely got some liquid leaking out, not every day but it's still not GONE. in addition to her hay, she gets a bucket with a handful of senior feed (mostly for palatability but more if I ever notice her weight go down which it hasn't recently), a scoop of Platinum joint formula, and salt. She used to get a little corn oil but I stopped in case it was worsening the poop issue. In the last month I have added shelf-stable ground flax, apple cider vinegar, and a probiotic in my efforts to clear up whatever is going on. I wonder if the bad hay caused lasting damage? Is it more likely to be ulcers or some other unrelated gut disease? Should I give the probiotics more time? The vet will see both horses this fall so I am hoping to have more questions and information to give her when she checks on this horse. Any ideas or suggestions? Thanks.