Join Date: Mar 2009
Location: Washington, USA.
Your barn owner is probably right, it's most likely the new batch of hay. I knew a gelding who was very sensitive to any feed change, and being in a barn with 16 or so other horses, they went through a lot of hay and bags of grain, so he never had time to fully adjust to anything to stop the diarrhea. My mare usually gets a little squirty [eww, lol] when she's in heat, and gets butt baths daily. There are products out to prevent scalding from it, but I can't think of what they're called.
So long as it's the right color, his temperature is normal, and his temperment/appetite is the same, I wouldn't worry about it until it's been a few weeks.
"Great spirits have always encountered violent opposition from mediocre minds."