I agree that a rotten tooth could certainly cause some bad breath in animals as well as us two legged human animals.
Back to the nutrition issue about the by products. They are not all bad in fact they can be just fine and dandy with our pets, but some companies can not exactly care what or where its coming from or even how its prepared when it comes to money matters.
The artical below can dispell some of the myths, and its just another article to consider when contimplating your pets health.
By-Products...
Are they getting a bad rap? As you read various pet food producers' advertising material you will often find such statements as "No By-Products Added!" or "Our food contains no animal by-products so you know it's top quality". I will let you decide if By-Products aren't good for dogs and cats after you learn what they are. To most people the term "by-products" congers up images of whatever is left over after the animal is processed, or maybe whatever can't be used for human food, or maybe even what's cleaned up off the processing floor at the end of the day. (I hear this misconception all the time!) It's time you learn what by-products are; so here is the legal definition as described by the official agency in charge of directing animal feeding practices in the U.S....AAFCO: Association of American Feed Control Officials.
By-Product... Secondary products produced in addition to the principal products. Well, there is nothing here to indicate good or bad quality of product. Maybe we should look at what the principal product is to find out what the secondary products are; then we can decide if the secondary products would make good food for meat-eating dogs and cats.
If Meat is the primary product (meat refers to the skeletal muscles of the slaughtered mammal) then ...
Meat By-Products - the non rendered (uncooked), clean parts, other than meat, derived from slaughtered mammals. It includes, but is not limited to, lungs, spleen, kidneys, brain, livers, blood, bone, partially defatted low-temperature fatty tissue and stomachs and intestines freed of their contents. It does not include hair, horns, teeth and hooves.
T. J. Dunn, Jr. DVM
Thomas712 - I like the second to the last line at the end it states "freed of their contents" can we always believe that? You can bet there are some well kept secrets about the pet food we buy, and there are some books on the subjects.
http://www.thepetcenter.com/imtop/nutrition.html
Anyone else finding this interesting?