That’s a good point. I also like alfafa for the stomach coating quality. With Yo and Melly I used soaked alfalfa cubes so they got alfalfa, AND water…
Magna lax buffers the tummy! It got my horse past his digestive issues. He is now eating 8-10 pounds a day and has picked up weight. Try this stuff. Dose him with it 15 minutes before you feed him. See if it makes a difference. It is CHEAP!
http://livestockconcepts.com/en/orals/266-magnalax-powder.html
Admittedly, I haven’t read all of the comments.
However, I took in a 29 year old with a BCS of 2. It took a few months to see the initial weight gain, then changes came rolling in. I was distraught for a few months though, I remember that. Good luck.