Do you mean the original Calf manna? or the newer Calf Manna meant for horses?
I've not tried the original calf manna in years, but on trying the newer one for horses, found that in a 6 month period it didn't really seem to make a difference for anyone that was put on it. I used it in 08 (larger ponies/full size horses) and again in 2010/2011 (shetlands).
When I was a teen/young adult - we used the original Calf Manna and LOVED IT. I will check it out and let you know how they all do.
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On the hay issue, I had a neighbor severely putting down the guy whose hay I have been mostly purchasing since June 2015 (or so?). But I purchased some small squares from him (choked on his prices!) and gave it a trial (before investing in his much more expensive round bales). Most that were offered - sniffed at it, picked thru some & nibbled - then turned right back to the "brown" round bales that we had. Of the ones who ate it a little better (but not like they would normally! and still went back to the "brown" hay), each had watery, foul smelling diarrhea w/i 12 hours. I will not be purchasing his much more expensive hay that our ponies don't like or appear to do well on.
I HAVE gotten other small squares from out of our area. Same prices, longer distances to go to get but yes, better quality (or at least prettier to look at). I bought the one guy out and he won't have any more until June... I will run out before then, even with only feeding a handful of ponies this hay. I have another supplier or two to check with.
Overall, the hay that I've gotten from the guy who doesn't spray any herbicides, while not pretty and yes, a problem with the Foxtail, the ponies did very well on - even when it looked not so good or weedy(I've only gotten a couple of bales that were moldy and he completely replaced those - others haven't). When I've gone back to purchasing from previous suppliers - every new load of hay brought a new round of nasty diarrhea. That was something we dealt with at the other property the last several years we were there. There were some that got their tails (and bums) washed fairly regularly - they just seemed to stay gross. A couple of times we missed it (not just me) and the farrier would get busy and OMG, what a mess that became! When we were talking about the different issues on the hay available here - she did seem surprised when we went back over pictures of ponies and hay - overall, there's been no to very little diarrhea here since January 2015.
Sometimes these things are so interesting... sometimes such a pain.
