Has anybody been trying the Purina Concept tubs? I have heard alot of good things about them. They are supposed to add body condition to a cow or heifer, and they are supposed to aid in the rebreeding process of first calf heifers. I bought two tubs last Wednesday, and put them out for my 25 heifers. The guy ay the feed store said I should see an increase in their body condition in as little as two weeks.