Reducing Fat in Milk and Dairy Products by Breeding

The potential is examined of selective breeding for altering the composition of milk to reduce fat and increase protein, if changes in consumer demand so dictate. The fat content of milk can be reduced markedly without great sacrifice in potential gains in yields of protein and solids-not-fat. This could be achieved through joint selection for either protein yield and ratio of protein to fat or solids-not-fat yield and ratio of solids-not-fat to fat, depending upon whether maximum yields of protein or solids-not-fat are desired. Estimates are given of the extent to which milk composition could be changed over specified times based on several selection strategies. Careful study of future demands for fat, protein, and solids-not-fat is required before changing current breeding practices which emphasize selection on milk yield and fat percent weighted in proportion to their approximate value in the pricing system.