Page:Popular Science Monthly Volume 80.djvu/76

72 consequently is more suitable for the food of infants. The fat in human milk is more finely distributed than in cow's milk, which also enhances digestion. Jersey cows furnish milk with a fat content nearly the same as human milk, but the fat globules are larger, and therefore Jersey milk is not as suitable for infants as milk from Shorthorns or Holsteins. The latter breeds produce milk with less fat than Jersey cows, but the globules are smaller.

It is obvious that human milk is the only perfect food for infants. If it is necessary to find a substitute we must be careful to select milk from cows whose product comes as near to human milk as possible. Here again it must be emphasized that mixed milk from a herd consisting of cows of different breeds, and in different stages of lactation, is the best milk to use. It is true that infants can adapt themselves to the use of a different milk from the one designed for them by nature, and it is fortunate that this is so. Cow's milk is the only available substitute for human milk. In some countries goat's milk is used, but this offers no advantages, and some disadvantages. Mare's milk or ass's milk is nearer in composition to human milk than other milks, but is difficult to obtain. Cow's milk serves the purpose very well, if it is derived from a mixed herd and obtained under cleanly conditions.

The essential points in producing healthful milk are to observe cleanliness in the process and to cool the milk rapidly and keep it cold. The result of a tendency to comply with these demands has been the establishment of dairies where milk is produced on scientific principles. The cows must be fed with wholesome fodder, must be kept clean and be in perfect health. Tuberculosis is detected by the most rigid test known, the application of tuberculin. This method shows the presence