Why does embryo transfer have only a limited application on commercial cattle properties but an extensive application on stud properties?

Because the females on the stud properties have been selected much more rigorously for superior genetic performance than those mutt cows that are raised on commercial operations. But commercial cows can be used to accept embryos to help grow the calves from the donor cow; however these cows, because of their otherwise inferior genetics and the fact most of them are crossbreds, cannot be used to produce embryos through the process of superovulation.