Iowa State Univ. managed grazing.

This is a pretty good video on how managed grazing is done.
and here is part 2

In this video, we learn that forage weighs about 200 lbs per inch per acre.
So if your grass is 10 inches high, you have about 2000 lbs of forage available. If you have a six day paddock system, and you cows weigh 1200 lbs:
1200 *.03 lbs of forage per cow day, 36 lbs per cow per day, times six days, 216 lbs of forage per cow, or 4.6 cows per acre to eat the desired 1000 lbs of forage.

We also learned about paddock shape and storing food (hay) to overwinter.

We learn about low impedance electric fence energizers, which are clearly best for our purposes.
We also learn that a main line energizer is much cheaper to run and maintain than a battery energizer.
Each paddock should have it's own water sources to reduce the traffic wear and tear. If they can be moved, all the better.

In part four, we learn about the plants on a pasture, how cool and summer grasses, along with legumes can be used to maximize growth in the pasture.  Growth is enhanced by the foraging of the animals, but at most 50% of the plant should be removed.

In part five, we learn about how to extend our pasture feeding into the winter months. Leave some pastures fallow and allow the cattle to graze on those until snow covered.