How To Curb Our Dog's Aggressive Behavior
We have a 14 month old male Australian Shepherd. We have had him for 12 months. He has gone through two complete series of manners' classes. He sleeps in a crate at night. He is outside most of the day. We bring him inside to be with us in the evening 'til we put him in the crate for bed. He learns quickly and for the most part is a good dog. He hardly ever barks, is friendly, and is completely in love with us. However, if he is not being petted almost constantly when we're with him, he becomes very demanding of attention. At that time he becomes aggressively playful and jumps on everyone and nips at their clothing all the while his butt is wagging and twisting.
We have tried to train him to act differently and have used Bitter Apple, etc. without success. However, he is strong and hard to discourage. He weighs around 55 lbs. The trainers have told us that he'll get better, but he seems to be getting worse. It was suggested by some of the trainers to enroll him in agility classes, but we had to drop out. He was so active that we couldn't get him settled down. We also take him to the dog park where he is very well-behaved once we get inside the park and he's free to run wild.
We would appreciate any suggestions. Thanks.