Hi Udi W:
Labs are so much fun!! I am not sure if you are concerned about his current weight or the possibility of gaining weight. It is best for his health to keep him lean by not overfeeding and to avoid over exercising him until he reaches maturity; less stress on growing joints. Here’s some more info:
/best-dog-foods/best-large-breed-puppy-food/
Here’s a thread about large breed puppy nutritional requirements. Read the first three or four pages and the links on the first page:
/forums/topic/large-and-giant-breed-puppy-nutrition/
On this page look for the post dated October 2, 2013 at 4:22 pm and follow the link to recommended large breed puppy foods. If you choose one of these foods I recommend contacting the company to be sure the calcium/phosphorous ratios are optimal for a large breed puppy, the list has not been updated for a few years.
/forums/topic/large-and-giant-breed-puppy-nutrition/page/36/
You could also join the Editor’s Choice for a current list of approved large breed puppy foods. Sounds like your pup is in good hands, good luck and have lots of fun with your boy!!
