Thin cows and first-calf heifers would be the most likely candidates. Tag calves at birth. Castrate, dehorn and implant bulls at birth. If possible, separate dry cows, first calf heifers and cow-calf pairs to feed more efficiently. Trim feet if needed, make sure bulls are in good condition and check with your veterinarian about breeding soundness exam.
Check cows frequently.
Be ready to provide assistance with calving if necessary. Over grazing can reduce winter forage production. Provide high magnesium mineral supplement for cows on winter grazing. Treat for lice if not already done. Keep a close eye on cattle when grazing on crop residues and residual summer grass.