Thanks for the replies here. It's still a mystery as to why that particular hay would have caused diarrhea. The comment which Dr. Kellon made regarding propionic acid was very interesting I thought, and as I have since learned and you also have said this acid is naturally occurring in the large intestine. With this factored in, and given the already high levels of FE in the water and soil where we live, I wonder it's (FE) the culprit?
"Dr Kellon has indicated it does introduce more acidity into the gut which could make iron more readily absorbed but only concern perhaps for iron overloaded horses."
I'm reading my Ucklele hair/mineral notes which refer to excess in FE causing "inflammatory illness". This is, of course, a very broad term, but could it be that high FE might cause gut inflammation? But how could this be if the microbial population is truly in balance? In any case, we have stopped using that hay - stopped the minute diarrhea was observed. Fortunately, I didn't buy that much, and any hay that's used from now on is inspected for substances which may feel like some sort of coating is there, and makes our skin burn!
Hooves did run slightly warm at CB's Wednesday; however, trimmer was out yesterday, and hooves are mont 5 of laminitis free. Perhaps we have skirted by. I did ask the grower, and he claimed he didn't use preservatives, and all of the horses eating that hay in the area were fine. This also may point back to FE, and if it's low in Durango, CO vicinity. I will also ask E-analytical next week, but I don't believe they check for this. Another question would be if there was a preservative or drying agent, could it be rinsed?
