What's Really in Pet Food
Plump whole chickens, choice cuts of beef, fresh grains, and all
the wholesome nutrition your dog or cat will ever need.
These are the images pet food manufacturers promulgate through
the media and advertising. This is what the $11 billion per
year U.S. pet food industry wants consumers to believe they
are buying when they purchase their products.
This report explores the differences between what consumers
think they are buying and what they are actually getting. It
focuses in very general terms on the most visible name brands --
the pet food labels that are mass-distributed to supermarkets
and discount stores -- but there are many highly respected
brands that may be guilty of the same offenses.
What most consumers don't know is that the pet food industry is
an extension of the human food and agriculture industries. Pet
food provides a market for slaughterhouse offal, grains
considered "unfit for human consumption," and similar waste
products to be turned into profit. This waste includes
intestines, udders, esophagi, and possibly diseased and
cancerous animal parts.
Three of the five major pet food companies in the United States
are subsidiaries of major multinational companies: Nestlé (Alpo,
Fancy Feast, Friskies, Mighty Dog, and Ralston Purina products
such as Dog Chow, ProPlan, and Purina One), Heinz (9 Lives,
Amore, Gravy Train, Kibbles-n-Bits, Nature's Recipe),
Colgate-Palmolive (Hill's Science Diet Pet Food). Other leading
companies include Procter & Gamble (Eukanuba and Iams), Mars (Kal
Kan, Mealtime, Pedigree, Sheba, Waltham's), and Nutro. From a
business standpoint, multinational companies owning pet food
manufacturing companies is an ideal relationship. The
multinationals have increased bulk-purchasing power; those that
make human food products have a captive market in which to
capitalize on their waste products, and pet food divisions have
a more reliable capital base and, in many cases, a convenient
source of ingredients.
There are hundreds of different pet foods available in this
country. And while many of the foods on the market are similar,
not all of the pet food manufacturing companies use poor quality
or potentially dangerous ingredients.
Ingredients
Although the purchase price of pet food does not always
determine whether a pet food is good or bad, the price is often
a good indicator of quality. It would be impossible for a
company that sells a generic brand of dog food at $9.95 for a
40-lb. bag to use quality protein and grain in its food. The
cost of purchasing quality ingredients would be much higher than
the selling price.
The protein used in pet food comes from a variety of sources.
When cattle, swine, chickens, lambs, or other animals are
slaughtered, the choice cuts such as lean muscle tissue are
trimmed away from the carcass for human consumption. However,
about 50% of every food-producing animal does not get used in
human foods. Whatever remains of the carcass -- bones, blood,
intestines, lungs, ligaments, and almost all the other parts not
generally consumed by humans -- is used in pet food, animal
feed, and other products. These "other parts" are known as
"by-products," "meat-and-bone-meal," or similar names on pet
food labels.
The Pet Food Institute -- the trade association of pet food
manufacturers -- acknowledges the use of by-products in pet
foods as additional income for processors and farmers: "The
growth of the pet food industry not only provided pet owners
with better foods for their pets, but also created profitable
additional markets for American farm products and for the
byproducts of the meat packing, poultry, and other food
industries which prepare food for human consumption."1
Many of these remnants provide a questionable source of
nourishment for our animals. The nutritional quality of meat and
poultry by-products, meals, and digests can vary from batch to
batch. James Morris and Quinton Rogers, two professors with the
Department of Molecular Biosciences, University of California at
Davis Veterinary School of Medicine, assert that, "There is
virtually no information on the bioavailability of nutrients for
companion animals in many of the common dietary ingredients used
in pet foods. These ingredients are generally by-products of the
meat, poultry and fishing industries, with the potential for a
wide variation in nutrient composition. Claims of nutritional
adequacy of pet foods based on the current Association of
American Feed Control Officials (AAFCO) nutrient allowances
('profiles') do not give assurances of nutritional adequacy and
will not until ingredients are analyzed and bioavailability
values are incorporated."2
Meat and poultry meals, by-product meals, and meat-and-bone meal
are common ingredients in pet foods. The term "meal" means that
these materials are not used fresh, but have been rendered. What
is rendering? Rendering, as defined by Webster's Dictionary,
is "to process as for industrial use: to render livestock
carcasses and to extract oil from fat, blubber, etc., by
melting." Home-made chicken soup, with its thick layer of fat
that forms over the top when the soup is cooled, is a sort of
mini-rendering process. Rendering separates fat-soluble from
water-soluble and solid materials, removes most of the water,
and kills bacterial contaminants, but may alter or destroy some
of the natural enzymes and proteins found in the raw
ingredients. Meat and poultry by-products, while not rendered,
vary widely in composition and quality.
What can the feeding of such products do to your companion
animal? Some veterinarians claim that feeding slaughterhouse
wastes to animals increases their risk of getting cancer and
other degenerative diseases. The cooking methods used by pet
food manufacturers -- such as rendering, extruding (a
heat-and-pressure system used to "puff" dry foods into nuggets
or kibbles), and baking -- do not necessarily destroy the
hormones used to fatten livestock or increase milk production,
or drugs such as antibiotics or the barbiturates used to
euthanize animals.
Animal and Poultry Fat
You may have noticed a unique, pungent odor when you open a new
bag of pet food -- what is the source of that delightful smell?
It is most often rendered animal fat, restaurant grease, or
other oils too rancid or deemed inedible for humans.
Restaurant grease has become a major component of feed grade
animal fat over the last fifteen years. This grease, often held
in fifty-gallon drums, may be kept outside for weeks, exposed to
extreme temperatures with no regard for its future use. "Fat
blenders" or rendering companies then pick up this used grease
and mix the different types of fat together, stabilize them with
powerful antioxidants to retard further spoilage, and then sell
the blended products to pet food companies and other end users.
These fats are sprayed directly onto extruded kibbles and
pellets to make an otherwise bland or distasteful product
palatable. The fat also acts as a binding agent to which
manufacturers add other flavor enhancers such as digests. Pet
food scientists have discovered that animals love the taste of
these sprayed fats. Manufacturers are masters at getting a dog
or a cat to eat something she would normally turn up her nose
at.
Wheat, Soy, Corn, Peanut Hulls, and Other Vegetable Protein
The amount of grain products used in pet food has risen over the
last decade. Once considered filler by the pet food industry,
cereal and grain products now replace a considerable proportion
of the meat that was used in the first commercial pet foods. The
availability of nutrients in these products is dependent upon
the digestibility of the grain. The amount and type of
carbohydrate in pet food determines the amount of nutrient value
the animal actually gets. Dogs and cats can almost completely
absorb carbohydrates from some grains, such as white rice. Up to
20% of the nutritional value of other grains can escape
digestion. The availability of nutrients for wheat, beans, and
oats is poor. The nutrients in potatoes and corn are far less
available than those in rice. Some ingredients, such as peanut
hulls, are used for filler or fiber, and have no significant
nutritional value.
Two of the top three ingredients in pet foods, particularly dry
foods, are almost always some form of grain products. Pedigree
Performance Food for Dogs lists Ground Corn, Chicken By-Product
Meal, and Corn Gluten Meal as its top three ingredients. 9 Lives
Crunchy Meals for cats lists Ground Yellow Corn, Corn Gluten
Meal, and Poultry By-Product Meal as its first three
ingredients. Since cats are true carnivores -- they must eat
meat to fulfill certain physiological needs -- one may wonder
why we are feeding a corn-based product to them. The answer is
that corn is a much cheaper "energy source" than meat.
In 1995, Nature's Recipe pulled thousands of tons of dog food
off the shelf after consumers complained that their dogs were
vomiting and losing their appetite. Nature's Recipe's loss
amounted to $20 million. The problem was a fungus that produced
vomitoxin (an aflatoxin or "mycotoxin," a toxic substance
produced by mold) contaminating the wheat. In 1999, another
fungal toxin triggered the recall of dry dog food made by Doane
Pet Care at one of its plants, including Ol' Roy (Wal-Mart's
brand) and 53 other brands. This time, the toxin killed 25 dogs.
Although it caused many dogs to vomit, stop eating, and have
diarrhea, vomitoxin is a milder toxin than most. The more
dangerous mycotoxins can cause weight loss, liver damage,
lameness, and even death as in the Doane case. The Nature's
Recipe incident prompted the Food and Drug Administration (FDA)
to intervene. Dina Butcher, Agriculture Policy Advisor for North
Dakota Governor Ed Schafer, concluded that the discovery of
vomitoxin in Nature's Recipe wasn't much of a threat to the
human population because "the grain that would go into pet food
is not a high quality grain."3
Soy is another common ingredient that is sometimes used as a
protein and energy source in pet food. Manufacturers also use it
to add bulk so that when an animal eats a product containing soy
he will feel more sated. While soy has been linked to gas in
some dogs, other dogs do quite well with it. Vegetarian dog
foods use soy as a protein source.
Additives and Preservatives
Many chemicals are added to commercial pet foods to improve the
taste, stability, characteristics, or appearance of the food.
Additives provide no nutritional value. Additives include
emulsifiers to prevent water and fat from separating,
antioxidants to prevent fat from turning rancid, and artificial
colors and flavors to make the product more attractive to
consumers and more palatable to their companion animals.
Adding chemicals to food originated thousands of years ago with
spices, natural preservatives, and ripening agents. In the last
40 years, however, the number of food additives has greatly
increased.
All commercial pet foods must be preserved so they stay fresh
and appealing to our animal companions. Canning is a preserving
process itself, so canned foods contain less preservatives than
dry foods. Some preservatives are added to ingredients or raw
materials by the suppliers, and others may be added by the
manufacturer. Because manufacturers need to ensure that dry
foods have a long shelf life to remain edible after shipping and
prolonged storage, fats used in pet foods are preserved with
either synthetic or "natural" preservatives. Synthetic
preservatives include butylated hydroxyanisole (BHA) and
butylated hydroxytoluene (BHT), propyl gallate, propylene
glycol (also used as a less-toxic version of automotive
antifreeze), and ethoxyquin. For these antioxidants,
there is little information documenting their toxicity, safety,
interactions, or chronic use in pet foods that may be eaten
every day for the life of the animal.
Potentially cancer-causing agents such as BHA, BHT, and
ethoxyquin are permitted at relatively low levels. The use of
these chemicals in pet foods has not been thoroughly studied,
and long term build-up of these agents may ultimately be
harmful. Due to questionable data in the original study on its
safety, ethoxyquin's manufacturer, Monsanto, was required to
perform a new, more rigorous study. This was completed in 1996.
Even though Monsanto found no significant toxicity associated
with its own product, in July 1997, the FDA's Center for
Veterinary Medicine requested that manufacturers voluntarily
reduce the maximum level for ethoxyquin by half, to 75 parts per
million. While some pet food critics and veterinarians believe
that ethoxyquin is a major cause of disease, skin problems, and
infertility in dogs, others claim it is the safest, strongest,
most stable preservative available for pet food. Ethoxyquin is
approved for use in human food for preserving spices, such as
cayenne and chili powder, at a level of 100 ppm -- but it would
be very difficult to consume as much chili powder every day as a
dog would eat dry food. Ethoxyquin has never been tested for
safety in cats.
Some manufacturers have responded to consumer concern, and are
now using "natural" preservatives such as Vitamin C (ascorbate),
Vitamin E (mixed tocopherols), and oils of rosemary, clove, or
other spices, to preserve the fats in their products. Other
ingredients, however, may be individually preserved. Most fish
meal, and some prepared vitamin-mineral mixtures, contain
chemical preservatives. This means that your companion animal
may be eating food containing several types of preservatives.
Federal law requires preservatives to be disclosed on the label;
however, pet food companies only recently started to comply with
this law.
Additives in Processed Pet Foods
Anticaking agents
Antimicrobial agents
Antioxidants
Coloring agents
Curing agents
Drying agents
Emulsifiers
Firming agents
Flavor enhancers
Flavoring agents
Flour treating agents
Formulation aids
Humectants
Leavening agents
Lubricants
Nonnutritive sweeteners
Nutritive sweeteners
Oxidizing and reducing agents
pH control agents
Processing aids
Sequestrants
Solvents, vehicles
Stabilizers, thickeners
Surface active agents
Surface finishing agents
Synergists
Texturizers
While the law requires studies of direct toxicity of these
additives and preservatives, they have not been tested for their
potential synergistic effects on each other once ingested. Some
authors have suggested that dangerous interactions occur among
some of the common synthetic preservatives.4 Natural
preservatives do not provide as long a shelf life as chemical
preservatives, but they are safe.
The Manufacturing Process
How Pet Food Is Made
Although feeding trials are no longer required for a food to
meet the requirements for labeling a food "complete and
balanced," most manufacturers perform palatability studies when
developing a new pet food. One set of animals is fed a new food
while a "control" group is fed a current formula. The total
volume eaten is used as a gauge for the palatability of the
food. The larger and more reputable companies do use feeding
trials, which are considered to be a much more accurate
assessment of the actual nutritional value of the food. They
keep large colonies of dogs and cats for this purpose, or use
testing laboratories that have their own animals.
Most dry food is made with a machine called an expander or
extruder. First, raw materials are blended, sometimes by hand,
other times by computer, in accordance with a recipe developed
by animal nutritionists. This mixture is fed into an expander
and steam or hot water is added. The mixture is subjected to
steam, pressure, and high heat as it is extruded through dies
that determine the shape of the final product and puffed like
popcorn. The food is allowed to dry, and then is usually sprayed
with fat, digests, or other compounds to make it more palatable.
Although the cooking process may kill bacteria in pet food, the
final product can lose its sterility during the subsequent
drying, fat coating, and packaging process. A few foods are
baked at high temperatures rather than extruded. This produces a
dense, crunchy kibble that is palatable without the addition of
sprayed on palatability enhancers. Animals can be fed about 25%
less of a baked food, by volume (but not by weight), than an
extruded food.
Ingredients are similar for wet, dry, and semi-moist foods,
although the ratios of protein, fat, and fiber may change. A
typical can of ordinary cat food reportedly contains about
45-50% meat or poultry by-products. The main difference between
the types of food is the water content. It is impossible to
directly compare labels from different kinds of food without a
mathematical conversion to "dry matter basis."5 Wet
or canned food begins with ground ingredients mixed with
additives. If chunks are required, a special extruder forms
them. Then the mixture is cooked and canned. The sealed cans are
then put into containers resembling pressure cookers and
commercial sterilization takes place. Some manufacturers cook
the food right in the can.
There are special labeling requirements for pet food, all of
which are contained in the annually revised Official Publication
of AAFCO.6 The use of the terms "all" or "100%"
cannot be used "if the product contains more than one
ingredient, not including water sufficient for processing,
decharacterizing agents, or trace amounts of preservatives and
condiments." Products containing multiple ingredients are
covered by AAFCO Regulation PF3(b) and (c). The "95% rule"
applies when the ingredient(s) derived from animals, poultry, or
fish constitutes at least 95% or more of the total weight of the
product (or 70% excluding water for processing).
Because all-meat diets are usually not nutritionally balanced,
they fell out of favor for many years. However, due to rising
consumer interest in high quality meat products, several
companies are now promoting 95% and 100% canned meats as a
supplemental feeding option.
The "dinner" product is defined by the 25% Rule, which applies
when "an ingredient or a combination of ingredients constitutes
at least 25% of the weight of the product" (excluding water
sufficient for processing) as long as the ingredient(s) shall
constitute at least 10% of the total product weight; and a
descriptor that implies other ingredients are included in the
product formula is used on the label. Such descriptors include
"recipe," "platter," "entree," and "formula." A combination of
ingredients included in the product name is permissible when
each ingredient comprises at least 3% of the product weight,
excluding water for processing, and the ingredient names appear
in descending order by weight.
The "with" rule allows an ingredient name to appear on the
label, such as "with real chicken," as long as each such
ingredient constitutes at least 3% of the food by weight,
excluding water for processing.
The "flavor" rule allows a food to be designated as a certain
flavor as long as the ingredient(s) are sufficient to "impart a
distinctive characteristic" to the food. Thus, a "beef flavor"
food may contain a small quantity of digest or other extract of
tissues from cattle, without containing any actual beef meat at
all.
What Happened to the Nutrients?
Dr. Randy L. Wysong is a veterinarian and produces his own line
of pet foods. A long-time critic of pet food industry practices,
he said, "Processing is the wild card in nutritional value that
is, by and large, simply ignored. Heating, cooking, rendering,
freezing, dehydrating, canning, extruding, pelleting, baking,
and so forth, are so commonplace that they are simply thought of
as synonymous with food itself."7 Processing meat and
by-products used in pet food can greatly diminish their
nutritional value, but cooking increases the digestibility of
cereal grains.
To make pet food nutritious, pet food manufacturers must
"fortify" it with vitamins and minerals. Why? Because the
ingredients they are using are not wholesome, their quality may
be extremely variable, and the harsh manufacturing practices
destroy many of the nutrients the food had to begin with.
Contaminants
Commercially manufactured or rendered meat meals and by-product
meals are frequently highly contaminated with bacteria because
their source is not always slaughtered animals. Animals that
have died because of disease, injury, or natural causes are a
source of meat for meat meal. The dead animal might not be
rendered until days after its death. Therefore the carcass is
often contaminated with bacteria such as Salmonella and
Escherichia coli. Dangerous E. Coli bacteria are estimated to
contaminate more than 50% of meat meals. While the cooking
process may kill bacteria, it does not eliminate the endotoxins
some bacteria produce during their growth and are released when
they die. These toxins can cause sickness and disease. Pet food
manufacturers do not test their products for endotoxins.
Mycotoxins -- These toxins comes from mold or fungi, such as
vomitoxin in the Nature's Recipe case, and aflatoxin in Doane's
food. Poor farming practices and improper drying and storage of
crops can cause mold growth. Ingredients that are most likely to
be contaminated with mycotoxins are grains such as wheat and
corn, cottonseed meal, peanut meal, and fish meal.
Labeling
The National Research Council (NRC) of the Academy of Sciences
set the nutritional standards for pet food that were used by the
pet food industry until the late 1980s. The NRC standards, which
still exist and are being revised as of 2001, were based on
purified diets, and required feeding trials for pet foods
claimed to be "complete" and "balanced." The pet food industry
found the feeding trials too restrictive and expensive, so AAFCO
designed an alternate procedure for claiming the nutritional
adequacy of pet food, by testing the food for compliance with
"Nutrient Profiles." AAFCO also created "expert committees" for
canine and feline nutrition, which developed separate canine and
feline standards. While feeding trials can still be done, a
standard chemical analysis may be also be used to determine if a
food meets the profiles.
Chemical analysis, however, does not address the palatability,
digestibility, or biological availability of nutrients in pet
food. Thus it is unreliable for determining whether a food will
provide an animal with sufficient nutrients.
To compensate for the limitations of chemical analysis, AAFCO
added a "safety factor," which was to exceed the minimum amount
of nutrients required to meet the complete and balanced
requirements.
The digestibility and availability of nutrients is not listed on
pet food labels.
The 100% Myth -- Problems Caused by Inadequate Nutrition
The idea of one pet food providing all the nutrition a companion
animal will ever need for its entire life is a myth.
Cereal grains are the primary ingredients in most commercial pet
foods. Many people select one pet food and feed it to their dogs
and cats for a prolonged period of time. Therefore, companion
dogs and cats eat a primarily carbohydrate diet with little
variety. Today, the diets of cats and dogs are a far cry from
the primarily protein diets with a lot of variety that their
ancestors ate. The problems associated with a commercial diet
are seen every day at veterinary establishments. Chronic
digestive problems, such as chronic vomiting, diarrhea, and
inflammatory bowel disease are among the most frequent illnesses
treated. These are often the result of an allergy or intolerance
to pet food ingredients. The market for "limited antigen" or
"novel protein" diets is now a multi-million dollar business.
These diets were formulated to address the increasing
intolerance to commercial foods that animals have developed. The
newest twist is the truly "hypoallergenic" food that has had all
its proteins artificially chopped into pieces smaller than can
be recognized and reacted to by the immune system.
Dry commercial pet food is often contaminated with bacteria,
which may or may not cause problems. Improper food storage and
some feeding practices may result in the multiplication of this
bacteria. For example, adding water or milk to moisten pet food
and then leaving it at room temperature causes bacteria to
multiply.8 Yet this practice is suggested on the back
of packages of some kitten and puppy foods.
Pet food formulas and the practice of feeding that manufacturers
recommend have increased other digestive problems. Feeding only
one meal per day can cause the irritation of the esophagus by
stomach acid. Feeding two smaller meals is better.
Feeding recommendations or instructions on the packaging are
sometimes inflated so that the consumer will end up purchasing
more food. However, Procter & Gamble allegedly took the opposite
tack with its Iams and Eukanuba lines, reducing the feeding
amounts in order to claim that its foods were less expensive to
feed. Independent studies commissioned by a competing
manufacturer suggested that these reduced levels were inadequate
to maintain health. Procter & Gamble has since sued and been
countersued by that competing manufacturer, and a consumer
complaint has also been filed seeking class-action status for
harm caused to dogs by the revised feeding instructions.
Urinary tract disease is directly related to diet in both cats
and dogs. Plugs, crystals, and stones in cat bladders are often
triggered or aggravated by commercial pet food formulas. One
type of stone found in cats is less common now, but another more
dangerous type has become more common. Manipulation of
manufactured cat food formulas to alter the acidity of urine and
the amount of some minerals has directly affected these
diseases. Dogs also form stones as a result of their diet.
History has shown that commercial pet food products can cause
disease. An often-fatal heart disease in cats and some dogs is
now known to be caused by a deficiency of the amino acid taurine.
Blindness is another symptom of taurine deficiency. This
deficiency was due to inadequate amounts of taurine in cat food
formulas, which itself occurred because of decreased amounts of
animal proteins and increased reliance on carbohydrates. Cat
foods are now supplemented with taurine. New research suggests
that supplementing taurine may also be helpful for dogs, but as
yet few manufacturers are adding extra taurine to dog food.
Inadequate potassium in certain feline diets also caused kidney
failure in young cats; potassium is now added in greater amounts
to all cat foods.
Rapid growth in large breed puppies has been shown to contribute
to bone and joint disease. Excess calories and calcium in some
manufactured puppy foods promoted rapid growth. There are now
special puppy foods for large breed dogs. But this recent change
will not help the countless dogs who lived and died with hip and
elbow disease.
There is also evidence that hyperthyroidism in cats may be
related to excess iodine in commercial pet food diets.9
This is a new disease that first surfaced in the 1970s, when
canned food products appeared on the market. The exact cause and
effect are not yet known. This is a serious and sometimes
terminal disease, and treatment is expensive.
Many nutritional problems appeared with the popularity of
cereal-based commercial pet foods. Some have occurred because
the diet was incomplete. Although several ingredients are now
supplemented, we do not know what ingredients future researchers
may discover that should have been supplemented in pet foods all
along. Other problems may result from reactions to additives.
Others are a result of contamination with bacteria, mold, drugs,
or other toxins. In some diseases the role of commercial pet
food is understood; in others, it is not. The bottom line is
that diets composed primarily of low quality cereals and
rendered meat meals are not as nutritious or safe as you should
expect for your cat or dog.
What Consumers Can Do
Who to Write
AAFCO Pet Food Committee
Dr. Rodney Noel -- Chair
Office of Indiana State Chemist
Purdue University
1154 Biochemistry Building
West Lafayette, IN 47907-1154
www.aafco.org
FDA -- Center for Veterinary Medicine
Sharon Benz
7500 Standish Place
Rockville, MD
20855
301-594-1728
www.cvm.fda.gov/
Pet Food Institute
2025 M Street, NW, Suite 800
Washington, DC 20036
202-367-1120
Fax 202-367-2120
References
Association of American Feed Control Officials Incorporated.
Official Publication 2001. Atlanta: AAFCO, 2001.
Barfield, Carol. FDA Petition, Docket Number 93P0081/CP1,
accepted February 25, 1993.
Becker, Ross. "Is your dog's food safe?" Good Dog!,
November/December 1995, 7.
Cargill, James, MA, MBA, MS, and Susan Thorpe-Vargas, MS. "Feed
that dog! Part VI." DOGworld, December 1993, 36.
Case, Linda P., M.S., Daniel P. Carey, D.V.M., and Diane A.
Hirakawa, Ph.D. Canine and Feline Nutrition: A Resource for
Companion Animal Professionals. St. Louis: Mosby, 1995.
Coffman, Howard D. The Dry Dog Food Reference. Nashua:
PigDog Press, 1995.
Corbin, Jim. "Pet Foods and Feeding." Feedstuffs, July 17, 1996, 80-85.
Knight-Ridder News Syndicate. "Nature's Recipe Recalls Dog Food
That Contains Vomitoxin." August 28, 1995.
Morris, James G., and Quinton R. Rogers. "Assessment of the
Nutritional Adequacy of Pet Foods Through the Life Cycle."
Journal of Nutrition, 124 (1994): 2520S-2533S.
Newman, Lisa. What's in your pet's food? Tucson
& Phoenix: Holistic Animal Care, 1994.
New York State Department of Agriculture and Markets. 1994
Commercial Feed Analysis Annual Report. Albany:
Division of Food Inspection Services, 1995.
Parker, J. Michael. "Tainted dog food blamed on corn." San
Antonio Express News, April 1, 1999.
"Petfood
activist." Petfood Industry, September/October 1991, 4.
Pet Food Institute. Fact Sheet 1994. Washington:
Pet Food Institute, 1994.
Phillips, Tim, DVM. "Rendered Products Guide." Petfood
Industry, January/February 1994, 12-17, 21.
Pitcairn, Richard H., D.V.M., Ph.D., and Susan Hubble Pitcairn.
Dr. Pitcairn's Complete Guide to Natural Health for Dogs &
Cats. Emmaus: Rodale, 1995.
Plechner, Alfred J., DVM, and Martin Zucker. Pet Allergies:
Remedies for an Epidemic. Inglewood: Wilshire Book Co.,
1986.
Rhode Island Department of Environmental Management, Division of
Agriculture. 1994 Report of the Inspection and Analysis of
Commercial Feeds, Fertilizers and Liming Materials. Providence:
Division of Agriculture, 1995.
Roudebush, Philip, DVM. "Pet food additives." JAVMA, 203
(1993): 1667-1670.
Rouse, Raymond H. "Feed Fats." Petfood Industry,
March/April 1987, 7.
Sellers, Richard. "Regulating petfood with an open mind."
Petfood Industry, November/December 1990, 41-44.
Smith, Carin A. "Research Roundup: Changes and challenges in
feline nutrition." JAVMA 203 (1993), 1395-1400.
Strombeck, Donald. R. Home-Prepared Dog and Cat Foods: The
Healthful Alternative. Ames: Iowa State University Press,
1999.
Winters, Ruth, M.S. A Consumer's Dictionary of Food Additives.
New York: Crown, 1994.
Wysong, R. L. "The 'complete' myth." Petfood Industry,
September/October 1990, 24-28.
[Wysong,
R. L.] Fresh and Whole: Getting Involved in Your Pet's Diet.
Midland: Wysong Corporation, 1990.
Wysong, R. L. Rationale for Animal Nutrition. Midland:
Inquiry Press, 1993.
Notes
1.
Pet Food Institute, 2.
2.
Morris, 2520S.
3.
Corbin, 81.
4.
Cargill, 36.
5.
The conversion is: ingredient percentage divided by (100 minus
moisture percentage).
6.
Official Publication, Regulation PE3, 114-115.
7.
Wysong, Rationale, 40-41.
8.
Strombeck, 50-52.
9.
Smith, 1397.
(Revised
08/04/04)
Copyright © 1997-2004 Animal Protection Institute.
Because this e-report is frequently revised, it is no longer
available in printed form. However, the fact sheet, "Selecting
a Commercial Pet Food," can be ordered from API.
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