Hi Kersten, probiotics would be my first suggestion but I see you are doing that. Have you tried doubling the dose to see if you get any improvement? I worked with a horse who had this and we were able to clear it up but I can't remember what we gave him. I will make a note to find out and send you a message sometime next week. In the meantime, you may want to see if you can find a homeopathic vet in the area to see if they can help you.
We are moving near Lacrosse as soon as we sell our house in NH!

Try searching here http://www.holisticvetlist.com/