I bought a Black Labrador Retriever on New Years Day last year, so he's not even a year old yet, but i find he gets terribly out of breath from doing the smallest things, like he'll chase a ball and bring it back once or twice and then he won't bother with it, he'll just sit there and pant very hard, and he's can't do anything while he pants, he has to sit there for a minute or 2 and do it. What I find weird is he can normally walk very well but just lately when i take him on walks he'll walk not even five minutes before he has to have a break, he's isn't overweight and is very healthy and has the strongest appetite i've ever seen in a dog, even if you put your hed to his chest while he's panting hard you can hear a kind of a wheezing noise. When we got him the papers said he was in perfectly healthy shape, it would be a shame if something was wrong with him. Anyone have this problem before???