You might consider having a separate facility for your calves to lay and eat. It might seem like a big expense only for calves, but the results may surprise you.
Having a separate feeding space and feeder made especially for your calves gives them the opportunity to put on all the pounds and growth possible. Consider building a feeder that is calf height and a smaller version of a cow feeder. Your calves will have the benefit of higher quality hay which results in more growth, fewer worms, and healthier calves.
A Clean Place To Lay
You might consider building individual calf stalls with shavings and straw for bedding. Offering a clean, dry place to lay and chew their cud allows calves to relax as well as get the most nutrition out of the cud. It is also a safe environment away from the cows, so injuries should be fewer.
When your calves have a place to eat and lay they become used to people being around and taking care of them. A sick calf becomes easier to catch and treat because you see the calves every day. Observing calves on a regular basis allows you to learn their habits and deal with issues in the early stages when treatment is easiest.