Purina Pro Plan Veterinary HA Hydrolyzed formulas contain hydrolyzed protein, which is a protein that has been broken down into small components to be less likely to cause an allergic reaction in food allergic dogs. HA Hydrolyzed formula uses a hydrolyzed soy protein since the most common ingredient that food allergic pets react to is animal protein (like chicken, beef, and fish). This high-quality protein source meets the pet’s dietary protein needs and the diet itself is formulated to be highly digestible to promote optimal nutrient absorption. It also contains coconut oil as a source of triglycerides to improve coat luster and shine. Please gradually introduce this new diet over about one week. Follow the guidelines for the amount to feed (based on weight) on the back of the bag of food. On the first day, the meals should be approximately 75% of the current diet mixed with 25% of the new diet. On each subsequent day please increase the percentage of the new diet and decrease the percentage of the current diet. By the end of the week, your pet should be strictly on the new diet with no added treats, table scraps, flavored toys, or supplements. If your pet refuses, or is not interested in the new diet, please notify our veterinarians for suggestions to make it more palatable, or for alternatives.