People tend to believe what their breeder tells them about food and what their vet tells them about food, but I would strongly suggest you don't do that. With breeders, it will be different with different breeders. What they feed will all depend on how much they really know about dog foods. With the vets, a vet will take one class on dog food and that's it. And, that one class will be taught be a dog food company. So, that vet learns what that company teachs them, that's it. It's not that your vet wants to lie to you about dog food, it's just that a lot of them really don't know about it.
So, that being said, I can't type as much as I really want to because my answer will get cut short. But, I will tell you some good things to look for and some bad things to looks for. Also, I have this kibble rating chart that I used a lot a couple years ago when I was doing research on different dog foods and the ingredients in them. You can go through the list of ingredients and rate them, then at the end you give the food an over-all score, so you can compare foods a whole lot easier that way. It is easy to use, but it's kind of long, so if you would like that, message me and I'll send it to you through a message.
Now, to know what foods are bad, a good rule is to just not buy any food from a grocery store, a place like Walmart, or a vet. Also, most foods you see on a TV commercial will be bad, and just recently, larger pet stores like Petco, actually started carrying good foods. I'd suggest you go to Petco, or a smaller pet store to find a food.
-To get back to the bad foods, any of the popular commercial brands, like Iams, Purina and Pro Plan foods, Beneful, Ol' Roy, Nutro, etc, are very low-quality foods.
-When you look at the ingredients in a dog food, you don't ever want to see any type of by-product, any type of animal digest, any type of corn (dogs cannot digest corn), or too many grains. You also want to stay away from beef unless you know that your dog is okay with it. A lot of dogs that have food allergies and sensitive stomachs won't do well with beef.
-The first 5 ingredients are the most important, and in the first 5 ingredients you will want to see some type of whole meat like chicken, lamb, turkey, some type of fish, etc. Also, meat meals are just as good, if not better, than a whole meat. For example, chicken meal, turkey meal, lamb meal, are all great things to see. The more meat or meat meals the better. Oh, another thing is that you need a food that has specific meats or meat meals. If the food says any of the meats or meat meals I have mentioned, that's good. But, if it just says meat meal, that's not good.
-Some good-quality foods would be, Natural Balance, Canidae (my husband and I feed our 3 APBTs the Canidae Grain Free), Solid Gold, Wellness Core, Innova Evo, Blue Buffalo, Organix, Halo, Chicken Soup For The Pet Lover's Soul, etc. Like I said before, most of what I just listed can now be found at Petco.. http://www.petco.com/Dog-Food.aspx But, smaller pet stores carry the foods like Canidae, which, like I said, is what we use.
-Okay, so I went over some of the the good and bad things. I told you what you don't ever want to see in a dog food that you buy, and I told you the good meats and meat meals. I also mentioned the grains, but to go into more detail, the grains aren't the best ingredient. Now, most of these good-quality foods will have at least some formulas that do have quite a bit of grains, but the less grains, the better. That's why we like the Canidae Grain Free. You don't want to see tons of rice, brown rice, oatmeal, etc. But, it's not bad like by-products and corn are either. You just want to look for a food with less grains. For example, these are both great foods, but look at the differences in the amount of grain and meat..
Canidae Grain Free All Life Stages:
http://www.canidae.com/dogs/grain-free-als/dry.html
Chicken meal, turkey meal, lamb, potatoes, peas
Wellness Super5Mix Chicken Reciepe:
http://www.wellnesspetfood.com/dog_wellness_dry_super5mix_complete_health_chicken.html?page=dog_wellness_dry_super5mix_chicken
Deboned Chicken, Chicken Meal, Oatmeal, Ground Barley, Ground Brown Rice
Again, both of those foods are wonderful quality foods. You really can't go wrong with any of the good-quality foods I listed, but I personally just like the ones with less grains. Especially if your dog has food allergies, the less grains the better. And, I do really like the foods that are all life stages, like our Canidae is, and like Natural Balance is, That means that you can feed that to your puppy, and as he grows, you don't have to keep changing his food.
Anyway, those are some of the most important things to know when picking a dog food. Again, if you would like that kibble rating chart, just let me know, but as long as you follow these tips, you will be good. Hope this helps, good luck! : )