Grain Free,ok for puppy????

I'm picking up my first puppy in 4 weeks ( the count down is on !!!!). We're not quite sure what mix he is, but the rescue is guessing Weim./ Rottweiler cross. and estimating the pups to mature at 70 to 100lbs. Anyways, I'm confused to what food to start him on. I feed my cats Orijen and think its an amazing food, and would like to put the puppy on that. But I'm worried about the whole protein/calories/calcium/etc.. debate. Even though Orijen has a large breed puppy food, does everybody think its a safe food to start a puppy on.

My other option is to start "puppy" on Canidae and then when he's old enough switch to grain free.

Any opinions? :)

I've had Baxter on Orijen regular puppy and wellness 95% beef, venison, chicken, turkey and salmon canned foods for 2 months now and he's been doing fine on it. I'm not sure about the large breed puppy food, I haven't looked at the calcium levels in it. That's the problem area with large breed puppy foods from what I've been led to believe, too high calcium can cause problems.

Cindy

By utilizing special low-ash chicken and fish ingredients, ORIJEN PUPPY LARGE avoids the high ash levels—and subsequently elevated calcium and phosphorus—that are a common concern for large breed puppy owners on high-protein diets.

The above statement is from Orijen's website: www.championpetfoods.com/orijen/products/puppyLarge.aspx ......I'm sure it is fine to feed your puppy. :)