We wormed the horse not long after we got him. Did it again 3 months later with a different wormer. Then he was on pennicillian for 3 days. I can't remember right now what for. I would have to ask my wife. After all this he got diarrhea, understandable. We had the vet come out, he reached his arm in his rectum to get a sample, and gave him a shot he said just in case of samolnela. And also took blood. The next day he called back and said he found nothing in his gut, no worms, no beneficial bacteria. He said to give him oats and probios for three weeks. About 2 weeks later the horse started to get cow patty looking poop. Then he started eating grass, then he went back to liquid poop. We now have him off the grass and are giving him grass hay and probios. The only vet around here seems like to me that it is a hassle for him to come out and do his job. I'm going to try what I;m doing right now to see if he does not get better. Any help would be great. Thank you all. I will keep you posted.