Normal Growth

Question
I have a six month old male black lab.  He is the most laid back lab I have ever met.  He seems very small to me.  He weighs 55 pounds and my vet said he probably won't get any bigger than that, but I find that hard to believe.  He is completely pure bred.  Is 55 pounds normal for a male lab?  Thanks!!

Answer
That is perhaps on the low end depending on his body condition.  He should still grow some more reaching 60 pounds or more by the end of the year.  You should be feeding an adult chow now. Switching to an adult chow for the larger breeds at 4 months, slows growth and helps develop sturdier joints.  Keep him lean for the same reason.  

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 and exercise adjusted to its individual needs. Here is a link to a good illustrated guide, http://www.longliveyourdog.com/twoplus/RateYourDog.aspx

For more on growth, see http://jn.nutrition.org/cgi/content/full/134/8/2027S