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.
