I use dimond High protien, good for the high energy hard working dog. I use it all year around and it is what my vet recomends. the High protine comes in a green bag. Other than what was already talked about diomond also has other kinds as well. They have a regular dog food in a red bag less protine then the Green bag. they also have a maintines formula for the fat dog and a high pro. high fat formula in a black bag. I get it from Bomgars stores. my local fur shop also carries it and most of the guys I know us it. i buy it in 20lb bags at about $10 a bad. the 40lb bag is about $15-$17.