Behavior Change

Question
I have a mixed lab that I adopted.  He is two and a half.  I have noticed recently that he is not as energetic as he normally is, he doesn't sleep on the bed with me any more, now he sleeps under it.  He still runs and plays when we go to the dog park and still loves to play catch with me but aside from that he is kind of a bum!  Four months ago we moved to Phoenix from Detroit, where he was in a house with another dog, and now he is the only dog, but that was four months ago... help!

Answer
He could just be settling down as his personality matures at 3 years old.  It wouldn't hurt to have the vet look at him either.  Check his body condition and have the vet confirm your judgement, http://www.puppychow.com/products/popup_body_condition.aspx  Continuing the same feed level at a lower activity level could cause him to gain weight, further reducing his activity level....