Variety is the Key:

People who I know and respect regarding dogs and dog nutrition recommend switching the protein every few months, this helps avoid the dog becoming allergic or intolerant to it.  For example:  if you are feeding a certain brand of kibble and they have beef, chicken, turkey, salmon, and lamb.  Switch between these proteins every few months.  Do the transition slowly.  However, kibble is not healthy for your pet, for many reasons. 

If you do insist on feeding kibble, please examine the label, and please try to get a kibble that isn’t full of filler and chemicals.  Any kibble you see that the first ingredient is corn, wheat, soy, and potato are not healthy for your dog because they are highly allergenic and because they contain so many carbs.  Dog’s didn’t evolve eating carb-heavy diets.  Some people theorize that the reason the majority of dogs are only living until 12 years old at most these days (and their last couple years are not healthy) is the carb-heavy diets they are fed.  Carbs make humans age faster and they make dogs age faster.  Carbs feed cancer.  Sadly, despite our best intentions, many pets are not living the long healthy lives we desire for them.  They are increasingly suffering from the same diseases that afflict humans (obesity, cancer, high blood pressure, heart failure, diabetes, allergies, etc).   This is due to diet.  You might want to reconsider what you are feeding your beloved pet.

Some vets are now starting to recommend canned food instead of kibble because of the moisture content – as long as it’s a BPA free can.  You would want to buy a “high end” canned food though, not the cheap stuff from the grocery store.

Most of all I recommend getting some raw meat and vegetables with every meal.  The best thing to do is finely chop fresh veggies that are dog friendly (a quick google search for a list). These days there exists dehydrated pre-chopped vegetable mixes for dogs – this makes it easy.  All that is required is rehydrating the vegetables (Dr. Harvey’s is a great company that makes mixes like this). There are even some mixes that include fruit.  As long as it is low sugar fruit – that is fine.  

I know raw meat is very controversial.  Think of it this way - coyotes and wolves don’t eat cooked meat and they don’t get salmonella or E.coli because their stomachs are extremely acidic.  The enzymes in raw meat are so good for dogs – they help prevent cancer and they help keep teeth clean.  One way to feed your dogs raw meat is to buy the dehydrated or flash-frozen dog foods that are available – they are expensive but significantly less messy and much more convenient.  Your dog doesn‘t need to have all raw meat all the time (mind you those dogs who do have that experience significant health benefits).   

If you can’t do raw with every meal at least try to do 1 or 2 meals per week that have some raw in them.  Also, giving your dog small amounts of lean meat table scraps is actually a good thing (make sure not over-spiced or coated in rich sauce or breading).