The label must list ingredients by weight in decreasing order. Ideally, the first ingredient is some form of animal protein. None of the other ingredients can weigh more than that first ingredient. Manufacturers have been known to get around this requirement by a practice called split-ingredient labeling, which involves spreading out, or splitting, ingredients of the same type so they appear farther down the label. For instance, a grain such as corn, rice, or wheat might appear on the label in several different forms, such as flour, flakes, middlings, or bran. A food labeled this way might end up containing more protein from plant sources than from animal sources.

When you find a food you like, check the label regularly to make sure the ingredients remain the same. The best manufacturers use a fixed formula, meaning that the ingredients don't change from batch to batch. Some manufacturers change ingredients based on availability and market price. Dogs often have sensitive stomachs and can suffer digestive upsets from this kind of unexpected change in ingredients.

Name Calling

Can you tell anything from a food's name? Surprisingly, yes. Strict regulations govern what a food can be called. Let's say that you're looking at a can that reads “Grandma's Chicken for Pugs.” That food must contain 95 percent chicken, excluding the water used for processing. Once the water is accounted for, the food must still contain at least 70 percent chicken. If the name includes a combination of ingredients — “Grandma's Chicken and Beef for Pugs” — chicken and beef must make up 95 percent of the total weight (excluding water), and the food must contain more chicken than beef.

A food name that contains a qualifying term such as “dinner,” “entrée,” “formula,” “nuggets,” or “platter” must contain at least 25 percent of the named ingredient — beef, for instance. So “Grandma's Beef Dinner for Pugs” contains at least 25 percent but less than 95 percent beef. What if Grandma makes a Beef and Chicken Dinner? The beef and chicken together must make up 25 percent of the product, with at least 3 percent being chicken.

Sometimes you'll see a label that highlights a particular ingredient; for instance, “Grandma's Chicken Dinner for Pugs ‘With Cheese.’” The label can read this way only if the added ingredient makes up at least 3 percent of the food. If it says “with cheese and bacon,” it must contain at least 3 percent of each ingredient.

Feeding Guidelines

The label also suggests amounts to feed. The operative word here is “suggests.” Each pug is an individual, so you'll need to experiment to find the right amount of food for your dog. Let your pug's condition be your guide. If he's a chubby puggy, cut back. If he looks too thin, add more. Remember that a growing or active pug needs more food than one that just lies around the house all day while you're at work. Ask the breeder how much your pug pup has been eating at each meal, and go from there.