A greyhound's diet will change quite dramatically over the course of his life in most cases. Proper nutrition is always important, but the nutritional needs of the greyhound vary with his stage in life, and his exercise levels.
Diet as Puppies
As puppies, weaned greyhounds are generally fed a mixture of goat's milk and rice cereal to help transition them to solid food. Greyhound puppies will then generally eat a diet composed of softened puppy formula kibble until they are ready to begin their racing careers or until they move into adoptive homes, if retired early.
Diet as Racers
As active racers, greyhounds are given a very-high-protein diet that is composed predominantly of a meat such as ground beef. The beef is typically mixed in and served raw, although some greyhound owners do cook the meat. This beef mixture, often referred to as "track food," will also typically include dry kibble, vegetables like potato, pumpkin, green beans or carrots, and some vitamin additives. Track food varies from one kennel to the next; however, all track food mixtures are high in protein, predominantly feature a single meat, and include vegetables or other supplements for complete nutrition.
Most greyhounds will eat a kibble-only diet in retirement, as recommended by adoption groups such as Greyhound Pets of America. The kibble should be a high-quality one and should be given in equal amounts twice daily. Good-quality kibbles will show a protein source—chicken, lamb and beef are typical—as the first ingredient. The kibble portions should be adjusted if a greyhound's weight starts to fluctuate away from its racing weight, until a proper "maintenance portion" is found, according to Greyhound Pets of America.
Some greyhounds eat a mixed diet, composed predominantly of dry kibble with various additions. Certain food additions may help to digestive problems: yogurt or canned pumpkin, for example, may be given for firmer stools. Other food additions are fish oil or brewer's yeast for shiny coat, or a cooked egg to stimulate the appetite of a reluctant eater. Some greyhound owners may regularly add any or all of these foods to kibble, making a gravy-type mixture by adding water. If water is added, it should be cold to avoid stripping the kibble of nutrients.