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Your Pet Food Probably Isn't Made of What You Think

TIME Health
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A new study published Tuesday night shows many pet food brands contain unspecified animal parts that aren't listed on labels.

The study, which was conducted by researchers at the University of Nottingham and published in the journal Acta Veterinaria Scandinavica, looked at 17 popular wet pet foods for both dogs and cats in U.K. supermarkets. They found that 14 of those brands contained cow, chicken and pig DNA—but none of the brands listed the animals explicitly on the label.

Of the seven products that displayed the phrase "with beef," only two had more cow DNA in them than combined DNA of chicken and pigs.

That might come as a shock to consumers, the researchers say, but by leaving certain animal parts off the label, the products weren't breaking any U.K. rules.

"Besides the customer not being able readily make an informed choice on the pet food product due to incomplete disclosure of ingredients (allowed by legislation), there could be the added complication of pet food allergies where a dog or cat could have adverse reactions to certain undeclared animal proteins in a product," says study author Kin-Chow Chang, a professor of veterinary molecular medicine at University of Nottingham.

Since the items in the study were purchased in the U.K., the findings don't necessarily apply directly to American pet food. But the pet foods studied are international brands, and by looking through regulation and labeling requirements for pet food by the U.S. Food and Drug Administration (FDA), what consumers may think is a full beef product, for example, could also have meat from other animals and still be abiding by proper U.S. regulation.

The FDA does not require pet food to have pre-market approval, but says pet food should be safe to eat, have no harmful substances and be "truthfully" labeled.

According to an FDA spokesperson, the FDA has its own pet food regulation, but individual states can also enforce their own labeling guidelines and may have adopted regulations suggested by the Association of American Feed Control Officials (AAFCO).

Under these regulations, “meat” that comes from cows, pigs, sheep, goats or any combination of these species can simply be called “meat” on pet food labels. Meat from horses or other species of mammals must be labeled to indicate the species of animal from which the meat comes (e.g. horsemeat or kangaroo meat). The term "poultry" can mean any mixture of species like chicken or duck.

You can determine a lot about what might be in pet food by how it is labeled. For instance, if a pet food product is called "Beef for Dogs," then 95% of the product must be beef. However, if a pet food product names an ingredient (like beef) in it's title, but the ingredient makes up less than 95% of the product (but at least 25%), then the name of the product must have a qualifying descriptive term added to it, such as "Dinner," "Platter," "Entree," "Nuggets" or "Formula."

The FDA gives the following example: "In the example “Beef Dinner for Dogs” only one-quarter of the product must be beef, and beef would most likely be the third or fourth ingredient on the ingredient list."

The researchers say their findings underline the need for better transparency among the pet food industry in order to help consumers make more informed choices about what they are buying for their pets.

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