Grazing frozen alfalfa/orchard grass

Have a 5 acre peice right next to the place that we seeded last spring with alfalfa and orchard grass with oats for cover. Took one cutting of oat hay July 1 and another cutting of regrowth mid August. It is looking quite good now with about 10 inches of og and alfalfa under that, been done growing of course since it froze.
Can/should a guy graze it and if so would any damage to the alfalfa be expected from less cover over the winter? We are in central MN. Its not fenced so temp electric wire would have to be strung out. Trying to decide if its worth it

The problem with grazing alfalfa with cattle is the damage their feet do to the crowns

I often will graze alfalfa in late fall after a good freeze. I wait until the ground is froze unless it is a dry fall, otherwise it can end up pretty rough. I'm still waiting to turn them out this year, hoping it stays colder after this week. I've grazed new seeding like you are describing and couldn't really tell that it hurt anything the following year, but I 've quit doing that and wait until the second year and beyond. No real reason, just makes me a bit nervous wondering if I will regret it in the spring. Make sure they are full before turning them out and keep an eye on them for the first day or two.

Thanks for the replies.
I had planned to leave it so it had a nice insulating layer of vegetation for winter but everytime i look at it it seems like a waste.
The bloat issue also concerns me but i would say at least half to 75% is grass so i would think that would help some

Yes, you could have grazed it. Alfalfa leaves drop off pretty fast after a killing frost so you are late.

Main winter kill factors are ground cover, snow cover, freeze/thaw cycles, age of stand, varieties planted. So grazing will effect one of main factors. Plant the tough stuff and graze on.

Well we let them in it today. If nothing else its distracting them from the calves we separated from them.