Hi there I use the shires one, it is good but does tend to rub so you have to do a lot of adjusting, and I think it gets very hot in humid weather inside the "bucket" bit of it.... definately an invaluable tool for controlling weight/laminitis though.
I used a grazing muzzel on my horse as shes prone to lami but she became dehydrated as she couldn't drink very well. I would say you would need to monitor your shetland to check it is drinking ok.
Yep definately put one on if you can't restrict your shetties grazing. I use a shires one and cut the hole a bit bigger so they can drink easier and eat a little bit.
Yes definitely. Daisy has one for when she can't be on restricted grazing. You may find that you need to cover it in fleecy material to stop it rubbing but I've not had a problem with Daisy being able to drink. The water just comes in through the holes nad the bucket and she drinks as normal. Its the eating that she finds tricky
They are a godsend!! I have the shires one for my shetland; they do tend to be a bit on the small side tho; shetlands are clever little souls and are quite good at eating and drinking plenty through them