There, I said it. Yes, he is big-boned, but he is also fat. And I've realized that his fatness makes him uncomfortable for me to ride with my hip issues. After taking three of my saddles to the chiropractor to sit in so that she can look at my position in them and tell me which is best and which is worse, I decided to just not ride in my western saddle anymore. At all. Since the chiropractor told me my jumping saddle was best, I went home and put it on Mac. I never rode him in it - always my dressage or western saddle, but the fit isn't too bad and so I got on, thinking it would magically solve my problems. Nope! Still the SI pain after riding him in it. Since I can ride the pony inn it without issue, I figured that the thing that is different is Mac.
I've not had this problem with him before, and the only thing that is different is that he's out on the grass (even though he wears a grazing muzzle) for 8 hours a day. So this is a management problem that I need to solve tout suite. Poor ponies - they all suffer for his fatness.
1) He needs to move more. I will now leave his paddock gate open overnight so he can wander around the sacrifice dry lot area. In the morning for breakfast, I put them all out there together. Since Mac is the boss (and he's not very nice about it), he will try to move everyone off a pile of hay (I put lots of piles out), so that keeps everyone moving.
2) He needs less grass. Back I go to moving horses multiple times a day! After breakfast I ride, so I like to keep them in the sacrifice area near the barn. After I ride, though, I will now move them to the larger dry lot area behind the house - again, with lots of piles of hay. I do weigh out the hay; it is easier to manage the calories than with grass, since I've had the hay analyzed and know what's in there. They are out in that area for the 8 hours that they would have been on grass.
3) I do want him to have a little grass, though, so remembering when we lived in CA that they would go out for a couple hours (and not blimp up), I now rotate them onto pasture for 2-3 hours before I bring them back to the barn for dinner.
4) A little less for dinner. They all get small-hole hay nets for dinner, but now Mac will just get less hay. Sorry, buddy, that's just the way it goes.
The vet was out yesterday for a dental appointment for him and I had her pull blood to see if there's anything we should be worried about. I'm interested to see the results.