No! Winter protection is meant to keep the ground frozen not keep it from freezing. It should be put on after the soil freezes. Besides if the steer manure is composted properly, it will not heat up as all activity that produces heat should be finished. Plain soil, shredded leaves, wood chips or shavings, or pine straw would be fine.
In your zone 8, you shouldn't need winter protection.

No No No.

If you mound with compost or manure, your roses will rot. Been there done that. I would find my roses were green above the compost, but totally black underneath it.

If I mound at all, I wait til a hard freeze (not frost - I mean in the 20s) and then I mound with pine shavings or fallen leaves.

Lots of people here, even in colder zone 7 Olympia, don't mound at all. You are as likely to lose roses to rot by mounding, as you are to cold by not mounding.

I didn't lose any roses this last winter even with single digit temperatures and a week of subfreezing temps. In December we went from a mild 45 degrees to about 20 degrees in two days, too. No time for plants to harden off. I scrambled to mound what I could in those two days, and it was enough. Only lost a couple of canes out of the whole garden. The rose society's garden, which is faithfully mounded every October with bark, had tons of winter damage, in contrast.

You can spread manure in the garden in fall or winter to break down slowly over the winter, but don't pile it up over the canes of the roses.