Abstract: The present invention provides a computer program for determining the optimum diet of an animal, determining what nutritional deficiencies exist in that diet, and formulating a supplement to correct those deficiencies. It allows the creation of a nutritionally complete and balanced diet with a sufficient but not excessive quantity of water, energy, protein, fat, carbohydrate, amino acids, fatty acids, vitamins, minerals, and vitamin-like nutrients. The specific compositions of supplements generated using the computer program are also claimed.