A new product/item we have added to our custom mix is working great on adding volume to our calves and they love to eat it, purina's pre-con. It is a cube high in fiber. Our calves love it and if you want extra fill on your calf at the show because they wont eat, feed them straight pre-con. We tried this because our feed store's purina rep mentioned it instead of depth charge. It shocked us that he would recommend something else other than depth charge to add volume to a calf. Something to think about. Also, another thing I like about it is it is a complete feed, so your not sacrificing your daily gain by feeding them just a filler.