The digestibility of a pet food is an important criteria because it directly measures the proportion of nutrients in the food that are available for absorption. Comparing several brands of dry processed foods will render digestibility coefficients between 69% to as high as 95%. Premium foods will usually have a higher digestibility coefficient. Most dog foods will produce products with a lower digestibility than human food. As the quality of the ingredients are increased, the food’s dry matter and nutrient digestibility increases. A raw food diet will have superior digestibility in excess of 90% and will contain an adequate supply of water that is self contained in the meat sources.
A lesser quality pet food that has a lower digestibility, contains a high proportion of ingredients that cannot be digested by the enzymes of the G.I. track. This results in partial or complete fermentation by colonic bacteria. Rapid or excessive bacterial fermentation leads to the production of flatulence (gas), loose stools, and occasional diarrhea. In addition to these side effects, a greater quantity of a poorly digested, food must be fed to the animal because the pet is absorbing a smaller proportion of nutrients from the feed. Please read my blog posted 1/8/08 that outlines the importance of nutrient utilization.
posted by Rob Mueller