A raw product is a raw, whole product that is cooked during processing to remove harmful bacteria, whereas a rendered product is cooked to remove the bacteria, but through extreme heat and pressure, water and fat are mostly removed, leaving primarily protein and minerals. 

• Meat (raw product): the clean flesh derived from slaughtered mammals and limited to that part of the striate muscle which is skeletal or that part which is found in the tongue, in the diaphragm, in the heart or in the esophagus; with or without the accompanying and overlying fat and portions of the skin, sinew, nerve and blood vessels, which normally accompany the flesh. It shall be suitable for animal food. If it bears a name descriptive of its kind, it must correspond thereto.
  
  In other words, meat is primarily the muscle tissue of the animal, but may include fat, gristle and other tissues normally accompanying the muscle, similar to what is sometimes seen in raw meat sold for human consumption. This may include the less appealing cuts of meat, including the heart muscle and the muscle that separates the heart and lungs from the rest of the internal organs, but it is still muscle tissue.
  • However, it does not include bone. Meat for pet food often is “mechanically separated,” meaning machines strip the muscle from the bone. This results in a finely ground product with a paste-like consistency (similar to what is used in hot dogs).
  •  In addition to using the term meat, the pet food manufacturer may also identify the species from which the meat is derived, such as beef or pork. However, to use the generic term meat on the label, it can only be from cattle, pigs, sheep or goats.
  •  If it comes from any other mammal (for example, buffalo or venison), the species must be identified. If the muscle is non-mammalian, such as poultry or fish, it must be called its appropriate identifying term.
    
    
• Meat Byproducts: the non-rendered, clean parts, other than meat, derived from slaughtered mammals. It includes, but is not limited to, lungs, spleen, kidneys, brain, livers, blood, bone, partially de-fatted low temperature fatty tissue and stomachs and intestines freed of their contents. It does not include hair, horns, teeth and hoofs. It shall be suitable for use in animal feed. If it bears a name descriptive of its kind, it must correspond thereto.
  • To put it another way, meat byproducts are most parts of an animal other than its muscle tissue—including the internal organs and bones.
  • Byproducts include some parts that some Americans eat (such as livers, kidneys and tripe), but also parts that they typically do not. Although the USDA does not deem certain byproducts, such as udders and lungs, edible for human consumption, they can be perfectly safe and nutritious for other animals.
  • As with meat, unless the byproducts are derived from cattle, pigs, sheep or goats, the species must be identified.
    
    
• Poultry: the clean combination of flesh and skin with or without accompanying bone, derived from the parts or whole carcasses of poultry or a combination thereof, exclusive of feathers, heads, feet and entrails. It shall be suitable for use in animal food. If it bears a name descriptive of its kind, it must correspond thereto. If the bone has been removed, the process may be so designated by use of the appropriate feed term.
  • Essentially, these are the parts of the bird as found in whole chickens or turkeys in aisles of grocery stores. Frankly, it often consists of the less profitable parts of the bird, such as backs and necks. Unlike “meat,” it may include the bone, which, when ground, can serve as a good source of calcium.
  •   If it is a particular species of bird, the more common name, such as chicken or turkey, may be used.

• Poultry Byproducts: non-rendered clean parts of carcasses of slaughtered poultry, such as heads, feet and viscera, free from fecal content and foreign matter except in such trace amounts as might occur unavoidably in good factory practice. If the product bears a name descriptive of its kind, it must correspond thereto.”
  • Similar to meat byproducts, these are parts of the bird that would not be part of a raw, dressed whole carcass, and may include the giblets (heart, gizzard and liver) or other internal organs, as well as heads and feet.