I forget the exact numbers but planted the cereal rye as if it was the only crop then 1/2 of the "only crop" rate for turnips in the small seed box. No till drilled in about now with a GP Solid Stand coulter type drill.  Cattle will pull most turnip bulbs. Turnips not grazed will winter kill here. With good fertility, cereal rye will come back strong in the spring.  May need some fertilizer in early spring to get the most out of the rye.

Obviously you need to fence them off of the new seeding now and again in early spring until rye is ready.