I bought some Angus cows with heifer calves on them early this fall that are supposed to have been bred back already and are supposed to drop this spring. He couldn't tell me when exctly they were bred or how old the calves were. What do i look for to know when they are about due? What will happen if the calves are not weaned by the time they have thier new calves? I am having trouble keeping them seperated to get them weaned.