Let's begin our foray into the world of commercial pet food ingredients. I'll feed it to you in small bites, because it's a lot of information!

Meat On pet food labeling, the word meat, or something more specific like lamb or beef, means muscle. According to the American Association of Feed Control Officials (AAFCO), meat must come from a mammal, and includes not just the kinds of muscles that people would normally eat but also muscle from the heart, tongue, diaphragm and esophagus. By AAFCO's standards, meat ingredients can include fat and skin, nerves, and blood vessels, but not entrails or hooves or things like that.

Also -- and this is important -- the meat that goes into pet food is not human grade. For most brands, it's the stuff that's been rejected by slaughterhouses as "unfit for human consumption." Fluffy and Fido are not getting the pet equivalent of your sirloin steak. AAFCO hasn't defined "human grade" ingredients yet, so even if you see that on a label, remember that it's a marketing claim and could mean anything.

We think: A good pet food will specify the kind of meat it contains. Unless you're a pet on a vegan diet (more on that in another post), you want a lot of your protein to come from meat, but pets don't like "mystery meat" any more than their people do, so seek out pet foods that tell you exactly what kind of meat you're dealing with.

Poultry Poultry (or chicken or turkey) means for bird products pretty much the same thing that meat means for mammal products. AAFCO's definition of poultry excludes feathers, heads, feet, and entrails, but it can include bones. Pet food manufacturers who use deboned poultry will often say so on their labeling.

We think: Poultry is tasty and a good source of protein. Of course, it's better if we know whether we're getting grilled chicken or a turkey dinner, so seek out labels with specific ingredient statements.

Meat and poultry by-products According to AAFCO's definition, by-product is the animal bits that aren't muscle. That includes stuff like:

• lungs, spleen, liver and kidneys
• brain
• blood
• bone
• stomachs and intestines (without their contents)
• poultry heads, feet, and innards

By AAFCO's standards, by-product does not include hair, horns, teeth, hooves, or fecal matter "except in such trace amounts as might occur unavoidably in good factory practice." Since AAFCO never defines "good factory practice," that could really mean anything.

We think: Unless your pet food brand is organic, avoid by-products. It's not that livers and kidneys are inherently bad for dogs and cats. In fact, there are lots of good nutrients in there -- if you know exactly where the organs are coming from, and how the animals were treated. Poor conditions at factory farms and slaughterhouses mean that the organs finding their way into your pet's food might be diseased or contaminated (lungs full of pneumonia, cirrhotic and worm-infested livers, that sort of thing). Pet food manufacturers can use 4D animals, which means entire dead, diseased, disabled (or downed) and dying animals deemed not suitable for human consumption can be used as meat by-product. This is not quality stuff. Garbage in, garbage out, as they say!

Next up: Why meat meal is the very last thing you ever want to see on a pet food label, ever. Seriously.

Photo by 3pom.