Definition: Meat By-Products are parts of slaughtered animals, not including meat (please note: no muscle meat included). Included are lungs, spleen, kidneys, brain, liver, blood, bone, partially defatted low-temperature fatty tissue, and stomach and intestines freed of their contents.
What AAFCO doesn't mention is that meat byproducts may also legally contain: "4D animals (dead, dying, diseased, down), road kill, euthanized cats and dogs, including their collars. These source products are rendered, the fat is siphoned off to be used as "animal fat," and the remaining material is extruded to form "meat by-product meal."
"Meat," by definition, is limited to the meats of cows, swine, sheep, and goats."
Also Known As: Meat By-Product Meal
Examples: Meat by-products is a substandard form of protein, used by many popular pet food manufacturers because it is cheaper than using muscle meat.