IMO the kibbles do not do much at all for tooth problems and decay and you can get the same benifits from giving them bomes and chews..those actually help out more.
Royal cainin is not a great dog food you can check out this site as a starting point on dog foods
http://www.dogfoodanalysis.com/ ...Dogs are optimistic carnivores they were not made to eat kibble they were made to eat meat vegtables and fruits.. (If my dogs had there choice they would want me too homecook for them but with 3 kids and 6 dogs that is not always an option-though I do cook for them sometimes

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If i was able to afford it (we have 6 dogs) I would feed all my dogs canned dog food only ..It is healthier for them.My dogs LOVE Merrick canned dog food and we are looking into there kibbles food now also(we like to keep our dogs on a variety)..We also feed Innova EVO Taste of the wild and
Orijen