I have a male german shepherd that's a little over a year old. Yesterday my roommate brought his older australian shepherd into the house and my dog doesn't know how to act. His dog is calm and older so when he's not here he leaves him out to roam the house. If my dog catches wind of this while I am home he freaks out and starts barking and whining in the kennel like he is being beaten. He has always been very loud and vocal and there are still times when he whines in the kennel for no reason but if he's crated and knows the other dog is out he goes ballistic. He also gets loud if I put him outside on his 30 ft lead to use the bathroom and he sees another dog running free but can't get to it. He's never bitten another dog aside from playing and doesn't have a mean temperament at all but if he sees something he can't get to he loses his mind and goes into a vicious sounding bark. All he ever wants to do is get right up in its face and investigate but naturally nobody wants to bring their dog around the dog barking like it's going to attack. The only time I can control this is if I have him on a leash with a prong collar or sometimes an e-collar if I'm in a remote area. What can I do to get him to stop barking at other dogs and other animals so much? My landlord's only condition for us having dogs was that they can't bother the neighbors and I'm afraid they're going to complain to him one day about my dog barking like he's in a dogfight. I was supposed to start an obedience program last week but they postponed it for another month because of low enrollment.