I have tried Elukanuba for my poodles, than changed to Royal Canin. That I am feeding last 18 months and let me tell you that all my dogz looks and feel in their best.
Royal Canin has a special prices for registered breeders - just get on their website, find a shop near you who stock it and ask for special breeders price, they can order you lge bags - that is a lot cheaper to buy in bulk specialy for lge breeds, they have a special food for special breeds, you will find labrador retriver specialy design food for that breed.
I hope that is use to you