Shanghai, not sure where you are, but those 40 pairs as you described them sounds like a chance to make some money. With 300 lb calves, they should be bred back 1st stage, so fall fresheners. Hold the calves on them until early June, they should weigh 550-600 and be worth 1100-1200 dollars per calf. That gets you down to 3rd period short solid cows with only 800-900 in the purchase price. Sounds like those cows weigh 1300, so they will probably weigh 1500 in August as springers and be worth 1700 or more----if you wanted to sell them then, that would be a very good profit, or you would have some cheap fall fresheners. Around here, a nice short solid cow that is springing will run from 1500-1750 each. A broken mouth springer is from 1300-1500 each.