Good neighbors have good fences, but also open them up for sharing the pasture. (Take that, Garret Hardin!)
I prefer bringing in sheep to graze because their light weight doesn’t create compaction the way these charismatic megafauna do, but the short turn-around time for grazing before seeding necessitated animals who could clear the cover crop quickly. Also, cow manure is more wet than sheep manure and has a good carbon-nitrogen ratio for immediate use.
Thanks, cows!