My son's competitive labs were sponsored by Nutro and they provided tons of financial support. Be he dropped them anyway, in part because the Nutro Rep would simply not answer any direct questions. He is now feeding a food manufactured from fresh verggies and meat, in the USA.
I had Shadow on Nutro Lg Breed Puppy food, and he wasn't growing well. At 3 1/2 months he only weighed 23 lbs and was undersized. He is now on Proplan and doing great. Almost up to average!!! No more Nutro for us.