Ash (also referred to as "crude ash," "inorganic matter" or "incinerated residue") is a regulatory or technical term that represents the mineral content of a food. Ash is what remains of a pet food after a sample is incinerated as part of a laboratory analysis.

The organic content (i.e., carbohydrate, fiber, fat and protein) will be totally combusted and only the minerals will remain (e.g., calcium, phosphorus, magnesium, etc.). The mineral content in pet food comes from ingredients and supplements added to the formula. Some regulatory agencies require pet food companies to declare ash content on the pet food label.

The choice of whether to feed a senior pet wet or dry food is ultimately dependent on the individual pet and owner's preferences. However, in certain cases, wet food can offer benefits for the older pet: Wet food is softer and easier for senior pets with missing teeth or other advanced dental issues to chew. Wet food, due to its high moisture content, may help keep senior pets hydrated.

Providing multiple water bowls can also help encourage drinking. Senior pets may have a decreased sense of smell and taste, which can affect appetite. Gently warming the food can help enhance its aroma and flavor. Whether feeding wet or dry food, food and water bowls should be located where senior pets can reach them easily. Elevating bowls a few inches off the ground may help senior pets with arthritis.