dog size?

Question
My labrador seems quite large he is not fat but is 53pounds at 5months old, is this larger than usual and what size is he likely to reach?

Answer
Your dog definitely should be narrower at the waist than the hips and chest.
You should be able to easily feel the ribs, but not see them.  Each dog is
different.  Standard recommendations are a good place to start, but each dog
must have its food adjusted to its individual needs. Here is a link to a good illustrated guide,
http://www.longliveyourdog.com/twoplus/RateYourDog.aspx

That doesn't sound too large, maybe on track to level out towards the top of the standard 55-75 pounds.  Keep him lean and switch to adult chow now.  That will delay reaching his final size allowing his joints more time to develop under less stress.