MSM and green-lipped mussel for osteoarthritis?

Good evening, I have a Cushing's horse (not an Ems) with mild osteoarthritis in his hocks. I wanted to ask if anyone has experience with the effects of MSM ( https://www.loesdau.de/pferdefit-by-loesdau-msm-1-kg-71719.html ) and green-lipped mussel extract ( https://www.loesdau.de/pferdefit-by-loesdau-muschelpulver-pur-100-g-7558.html ) on osteoarthritis, and whether both can be fed together. Also, whether either of these could have…

Cushing horse feeding?

What do you think about feeding my 22-year-old Icelandic horse who suffers from Cushing's disease? Hay cobs or molasses-free beet pulp Digestive Mash Original Country Mill Ginger powder Zinc Plus Original Landmühle chasteberry rose hips corn flakes Garlic Mineral Sticks Salt Cinnamon All of this is poured over with hot tea. Otherwise, he gets hay…