So, I work in a dog daycare (have been for 18 months now) and I've come across a dog with a problem I'm kind of perplexed about. Stoli is a 11 month old Bullmastiff mix, neutered, and plays pretty well in daycare except for certain .. outbursts? His owner is employed under the company I work for in our head office so luckily when he misbehaves he would go up to hang in her office. Anyways, when he's playing he'll grab the skin around the face and neck with his front teeth and *will not* let go. The last day he was walking past a adolescent lab, and just grabbed his neck. McGruff sqeauled and Stoli shook him and shook him HARD (McGruff was fine afterwards with no injuries or hurt feelings). Stoli has been banned until further notice however I don't know what else to tell her besides training basic obedience, more mental stimulation and exercise. He seems pretty self involved, and doesn't really acknowledge my existance, or any of the caregivers. Just a poorly behaved adolescent dog... however he treats dogs like toys and I just don't know how she would fix it. Are there any books she should read? I've already told her that he just may not be suited to daycare as well. However she would like to see if there is anything she can do to turn that around.