[quote1329013212=Castanha] David, how would you compare the dog you had, with the one you have now? i.e. drive, strenght, temperament, etc... thanks [/quote1329013212] To be honest with you he was first dog an I tried to play Cesar Milan with him. I didn't do my research and I rescued him at 5-6 months old. The dog was crated, never walked and didn't even know what a collar was. I neutered him as soon as I got him and used to drop him off at doggy daycare, that goes to show you how uneducated and naive I was. By the time the dog was a year old he couldn't see anything with furr and couldn't take him to the vet anymore because they told me that he would growl and snap at them. He was a walking law suit waiting to happen. I am unsure if his energy derived from his insecurity and deffensive Agression. But this dog could hike for miles, he could run 20 minutes on the treadmill with a 5 pound backpack on incline and soon as I would get him off it he would run laps in the yard like he never did anything on the treadmill. He had very good heat tolerance, he was extremely agile and fast. He didn't have much of a mouth though was not a dog that likes to tug. My current dog is about 20 pounds heavier, with a much slower metabolism. My dog has less heat tolerance but I believe he has more initial power output, but once he releases his force he is done. While Pluto the yellow dog wasn't as powerful but his energy levels stayed on longer. I think Bernie is much stronger but lacks the wind and prey drive Pluto had. Overall I think plutos build made him a long distance athlete while Bernie is more of a powerful lifter with short stamina. Bernie is super submissive with us while Pluto was dominant so again I think his personality could have powered his everlasting energy.