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By Dr. Donna Spector
Following is a series of posts that will help educate pet owners about reading labels and choosing foods they can trust for their pets. It is easy to be fooled by marketing gimmicks and misleading label claims … pets don't question what they eat … so we must.
What is really in pet food?
The pictures presented on cans and bags of pet food conjure up images of a chef cooking divine meals of wholesome cuts of meat and vegetables for our beloved pets. Although this is a lovely idea, it is rarely the case. When animals are slaughtered for food production, the lean muscle is cut off for human consumption. The remaining carcass (bones, organs, blood, beaks, etc.) is what goes into pet food, commonly known as "by-products," "meal," "by-product meal," or the like. Read on if you are not faint of heart.
In addition to the carcasses described above, other "leftovers" from the human food industry (restaurant grease, out-of-date supermarket meat, etc) and "4D" livestock animals (dead, dying, diseased, disabled) may also be found in pet food through a process called rendering. Rendering is defined as "an industrial process of extraction by melting that converts waste animal tissue into usable materials". In other words, rendering involves placing livestock carcasses and possibly "leftovers" into huge vats, grinding it up and cooking it for several hours. Rendering separates fat, removes water, and kills bacteria, viruses, parasites and other infectious organisms. The fat that is separated becomes "animal fat" that goes into pet food (for example, chicken fat, beef fat, etc). The remaining dried protein solids become "meal" or meat "by-product meal" for addition to pet food. Read on for some additional disturbing definitions:
By-products (for example, chicken by-products or beef by-products): clean non-rendered "parts", other than meat, derived from slaughtered mammals. It includes, but is not limited to lungs, spleen, kidneys, brain, blood, bone, fatty tissue and stomachs and intestines freed of their contents. This is a cheap way for pet food companies to keep the protein levels "high" (although not high quality) while keeping food production costs low.
Meat Meal (for example, lamb meal): in this example, all lamb tissues, exclusive of blood, hair, hoof, horn, hide trimmings, manure, stomach and rumen contents that are cooked (rendered). After cooking, the dried solids are added as "meal" to pet food.
Meat By-product Meal (for example, chicken by-product meal): chicken by-products (defined above) that are cooked (rendered). After cooking, the dried solids can be added to pet food.
Digest: material from mammals which results from chemical breakdown of clean meat tissues or by-products ("parts" other than meat). This is often used to give a meat "flavor" to pet foods that don't contain any real meat.
The raw ingredients used in rendering are generally just leftovers of the meat, poultry and fishing industries. It is known that the temperatures used in rendering may also alter or destroy natural enzymes and proteins found in these raw ingredients. These facts indicate there is potentially wide variability in nutrient composition of the final product that ends up in pet food. In fact, the nutritional quality of by-products, meals and digests often varies dramatically from batch to batch.
All rendered products are considered "unfit for human consumption." If we shouldn't eat it, either should our pets! Rendered products typically have relatively high protein levels, however, the quality of those proteins is often questionable. In fact, these inferior protein sources are often unpalatable to pets and artificial flavors or fats must be sprayed on the food in order to get pets to consume it.
Interpreting label claims
So how do you decipher what pet foods are truly high quality? It is often misleading when pet foods are labeled as "premium," "super premium," "ultra premium" or "gourmet." What does all this really mean and is it worth the extra money? Well, mostly … the labeling is just hype. Products labeled as premium or gourmet are not required to contain any different or higher quality ingredients than any other complete and balanced product.
Pet foods labeled as "natural" do fall under the jurisdiction of the Association of American Feed Control Officials (AAFCO), the regulating body for pet food manufacturers. AAFCO defines "natural" pet food as having ingredients from ONLY plant, animal or mined sources. These foods cannot be highly processed or contain chemically synthetic ingredients, such as artificial flavors, preservatives, or colorings.
"Organic" pet foods are those made without the use of conventional pesticides and artificial fertilizers, free from human or industrial waste contamination and processed without ionizing radiation or food additives. If food animals are involved, they must be raised without the routine use of antibiotics and growth hormones and fed a healthy diet. Producers must have special certification and follow specific production standards in order to market the food as organic. There are different levels of organic: "100% organic" is just that, "Organic" contains at least 95% organic ingredients and "made with organic ingredients" indicates a product contains 70% certified organic ingredients.
The term for domesticated farm animals that are raised for work, wool, milk, and other products and uses. May include pigs, cows, horses, and poultry.
To slow something down or cause it to stop
The group of processes that involve the use of nutrients by the body
A chemical change that has to do with adding oxygen or something like it
Something that is artificially created
Less important, below, toward the bottom or back
The hard outside of the feet of certain animals, like horses, cattle, goats, and pigs
The outbreak of a disease inside of a group
Any product that is derived from but less in value than another product from the same source.
The digestive tract containing the stomach and intestine
Fat or lanolin
A medical condition in which the joints become inflamed and causes a great deal of pain.
A type of system that is used to compare animals within a given group to one another