I have 2 awesome beagles. One is a 2 year old male (Cooper) and the other is his 1.5 year old sister (Rocky). Up until 6 months ago they were both very typical beagles, I mean they were always getting into trouble of course but never exhibited any type of aggressive behavior. About 6 months ago though I had Rocky spayed. When I brought her home Cooper immediatly knew something was wrong and for the next 2 days never left her side. Our friend came over that day to visit and brought his dog, who cooper and rocky both love to play with, but when he approched Rocky, Cooper started growling and ran him away from her. We thought that maybe he just knew she was not feeling well because of the surgeory and was looking after her and he would stop in a day or two. About a week later we took the dogs to our usual dog park and at first everything was normal, they were running around and sniffing the other dogs, but after a while we started to notice that Cooper would start growling at any dog that came near Rocky and he would chase them off. He has since got alot better with our friends dog and a couple of other dogs that he knows very well, but any strange dog that he doesnt know that approaches his sister he immediatly becomes very protective of her. This is not normal behavior for him, like I say up until 6 months ago he got along great with any dog, weather he knew them or not. This has got us a little worried because we dont know why this has happened. We just want them to be able to go to the park like they used to and play and have fun again. Any advice would be greatly appreciated. I posted a few pics of my guys
http://i27.photobucket.com/albums/c199/ajr666/highres_3086770.jpg
http://i27.photobucket.com/albums/c199/ajr666/highres_3086508.jpg
http://i27.photobucket.com/albums/c199/ajr666/100_0755.jpg
http://i27.photobucket.com/albums/c199/ajr666/highres_3086770.jpg
http://i27.photobucket.com/albums/c199/ajr666/highres_3086508.jpg
http://i27.photobucket.com/albums/c199/ajr666/100_0755.jpg
