I just purchased a pet rabbit to help train my beagle pup. The pup is 15 weks old. The pup seems to be doing well at sight chaseing. The question I have is this. When the rabbit is in his pen (Pen is on the ground ) The pup will hang around the pen and bark up a storm. How long can I leave him at the pen ? I am scared if I leave him to long he will loose interest.