Can I feed protein out of a feeder ??
Assuming you mean a timed broadcast feeder. The short answer is yes you can. If you are doing it with the intent that you are going to see the preferred results of supplemental protein feeding, I'd spend my money elsewhere. Free choice feeders for protein would be the preferred method if you are seeking to achieve some level of improvement to overall deer health, increased body weight, improved antler development, increased fawn survival, etc