When comparing pet food labels, the simplest method is to compare like products; that is, canned with canned or dry with dry. You cannot directly compare a canned food label with a dry food label; the information in the labels’ guaranteed analysis in both pet food products must first be converted to a dry matter basis before the comparison is valid.
For canned foods: Multiply the label nutrient values by 4 to get dry matter basis. For example, take a label value of “5% protein” x 4 = 20% on a dry matter basis.
For dry foods: Add 10% of the label nutrient values to get dry matter basis. For example, take a label value of “20% protein” + 2 = 22% on a dry matter basis.
||We have a simple calculator that allows you to compare different foods on a dry matter basis; click the calculator to the left to try it.
You may compare the Guaranteed Analysis information and/or the Ingredient List, but there are pitfalls to avoid:
These guarantees are required (in this order):
Crude Protein (Minimum Percentage)
Crude Fat.....(Minimum Percentage)
Crude Fiber...(Maximum Percentage)
These are the only required guarantees. “Moisture” or water content is the only value regulated in the USA, where it cannot exceed 78% in a pet food without certain label designations. The pet food company determines the actual minimum or maximum value for the other three nutrients on the label. Higher or lower nutrient guarantees are thus not measures of product quality and should not be used when deciding which pet food product is appropriate for your pet. Some pet food labels have other nutrients listed such as ash, magnesium, or taurine guarantees if the company thinks this will influence consumers.
The accuracy of the guarantees are rarely tested and substantiated by an outside independent group. There are no guidelines by which one can assume the actual nutrient content from the min or max on the label. Laboratory analysis of the nutrient profile is expensive and even then only one can or bag can be analyzed at a time, which may not be a representative sample.
Perhaps the most valuable information on the product label is the manufacturer’s phone number or web site address. Requesting the average or target nutrient profile from the manufacturer directly is the most reasonable method of obtaining nutrient profile data on a product. This information, matched with the Nutritional Adequacy Statement and the actual response of your own pet, is the most reliable measure of the best food for your pet.
The ingredients are supposed to be listed in order by weight, but unfortunately this is very difficult to monitor and enforce. Also, unfamiliar terminology is used in the ingredient list, and anyone reading a pet food label can be confused by the terms. Further, it is difficult to separate nutritional fact from gossip in popular press articles and advertisements. However, each term used in the ingredient list does have a specific AAFCO definition, and you can learn the ingredient description and composition from the AAFCO manual. See examples of Dry Food and Canned Food Labels above.