Re: Asking for grazing muzzle input
I have no fewer than five horses muzzled at a time, so I have a lot of experience with muzzles.
This was a fit problem combined with boredom and frustration.
I have found that the best fitting, longest lasting muzzles are the Deluxe Best Friends muzzles. These come with an attached halter so that you can customize the fit well. The halter needs to fit like a well fitted halter, and I find the basket , for my 14.3 hand Morgans still needs to be the oversize horse ones, any smaller and they rub the jaw, etc. The muzzle bottom needs to hang about an inch below their lips and no farther. Best Friends website has a great video on how to fit, introduce, etc.
I personally wouldn't muzzle a horse under the circumstances you mention. You have your horse in a grass free paddock , and if you muzzle him, now he has nothing to do but focus on getting the muzzle off. I would suggest you put high quality, low calorie hay in either a hanging bag on a pole, or use the hay bags made for ground feeding, such as hay pillows. https://www.thehaypillow.com/ Put a couple out so he can check out both as he pleases.
IME, muzzles work really well to limit grass intake, not eliminate it. If you have a horse that cannot have any grass, a muzzle won't help and the horse is going to start working on getting it off via hooking it on the fence, etc. Once the fence is down and the muzzle is off(he will paw it off because he won't know how to eat through it,( they do need to learn how to wear one and eat/drink with it for those on grass turnout in one), and he'll be out on pasture snarfing it up.
I would do everything I could to make him happy and content in his paddock. You can add a small pan of soaked ODTBC's as a treat, etc.
Other's may have different opinions and experiences , but I have spent almost ten years with horses in muzzles and the above is what I find works consistently. The oversize muzzle is most easily found and ordered via Best Friends website, their service is great and ship quickly.
Saline, MI 2003