If you are a pet owner, chances are you have picked up a bag of pet food and found reading the label to be very confusing.  You see things you recognize like “ingredients”, “net weight”, “manufacturer name” and more.  You will also see a “Guaranteed Analysis” panel on the label but may not really understand what that indicates. 

AAFCO, the Association of American Feed Control Officials, is the organization that is responsible for regulating labeling of pet foods.  One of these regulations require pet food manufacturers to list a “guaranteed analysis” of that particular food and that it includes at least 4 pieces of information – protein, fat, fiber and moisture. This information is shown in percentages and there is also wording that indicates it is either a minimum level of that nutrient or a maximum amount.   So, you might see an analysis that looks like:

               Crude Protein                    27% minimum

               Crude Fat                            15% minimum

               Crude Fiber                        6% maximum

               Moisture                             10% maximum

It means that this food contains at least 27% protein and no more than 6% fiber.  There could be a higher amount of protein but it will not be below 27%.  The term crude only refers to the method of testing the food, not to the quality of the ingredients themselves.  You may also see “Ash” listed in the analysis.  Some pet food manufacturers include this information and others don’t.  Ash sounds like something added to the food but it is really a measurement of the mineral (iron, zinc, etc) content.  If you incinerated the food and all the ingredients and moisture were burned away, what would be left are the minerals or “ash”.

Guarantees are also made on an “as is” or “as fed” basis.  This is not too important if you are comparing two brands of dry food with the same moisture content.  But if you are trying to compare products with different moisture contents like a canned food with a bag of dry, you will need to convert each to a “dry matter basis” or DMB.  DMB means removing the moisture content and comparing the “dry matter” that is left.   Let’s say we have a canned food with the following guaranteed analysis:

               Crude Protein                    8.0%

                Crude Fat                           1.4%

               Crude Fiber                        0.5%

               Moisture                             86.0%

               Ash                                       1.2%

Suppose you are looking for high protein content for an active dog.  To compare the dry food to the wet food we first have to remove the moisture content from both.   To calculate that subtract the moisture content from 100.  That gives us 90% dry matter for the dry and 14% for the canned food.  Now we need to figure out the dry matter percentage of both foods protein by using a formula – (Protein/dry matter)*100.  Our dry food is (27/90)*100 = 30% protein.  The canned food is (8/14)*100 = 57% protein.  You can use this same formula to determine the DMB for each of the other ingredients. 

Understanding pet food labels can help you choose the most appropriate diet for your pets.  We are always happy to help you decipher a label, so please ask any time you need assistance.