I have written about the benefits of feeding your pet a high quality, natural, holistic or organic diet. When you switch your pet from one food to another there needs to be a transition time to avoid upsetting your pets digestive system.
Start by adding 25% (1/4) of the new food for about 5 days, increase to 50% (1/2) of the new food for about 5 days, and then add 75% (3/4) of the new food for 5 days. This schedule should prevent any problems transitioning to a new high quality food.
Your pet may eat less on a quality food because they are getting the nutrients they need. You will also notice less stools to clean up when your pet is on a better diet.