One thing most producers overlook about stock cows is the condition of the rumen. I had an old rancher tell me,"don't feed the cow feed the rumen". Think of the rumen as a mobile septic tank. The heat of the bacterial growth help keeps the cow warm, digest coarse forage, the digestion of dead bacteria in the rumen, account for a significant percentage of the protein intake of the cow. Keep salt ( i used only red blocks) in front of cow all the time. Cows will consume more salt on a coarse diet. The salt stimulates a gland at the back of the mouth that excretes an amino acid, which in turns enhances bacteria growth in the rumen.