Page:Popular Science Monthly Volume 73.djvu/173

Rh is the one toward which breeding efforts and the attention of the consumer should be directed. As protein, the tissue former, is the most valuable constituent of milk, it follows that an endeavor to insure a high percentage of this indispensable food element should be the aim of any legislative enactments having in view the establishment of milk standards (of which we hear so much in this day) and not the maintenance nor increase of the fat content. And when it is understood, moreover, that as the fat content of milk increases, the tendency probably is toward the decrease of the proteid content, the folly of this course becomes patent.

Legislative measures referable to the production, transportation, sale and consumption of milk have had and will continue to have a most important, direct and indirect influence upon the character of the herds supplying the milk to the several communities in which such legislation is operative.

As laws represent the will of the majority and as the majority in this instance are the consumers, it behooves us, as such, to understand what is desirable in the matter of milk and then through educational effort work toward the attainment of it.

A word here regarding the leading characteristics of breeds of cattle may not be amiss. All cattle may be roughly divided into three general classes according to the purpose for which they are designed—the beef breeds, the general purpose breeds and the dairy breeds, with the last of which only we are concerned. The dairy breeds are again roughly divided into two great classes.

First, those who give large quantities of milk containing a normal proportion of fat divided into small globules. Of this type the Holsteins and Ayrshires are examples.

Second, those in whose milk a large percentage of fat is found in the form of large globules but who in general are somewhat delicate and comparatively small milkers.

Jerseys and Guernseys are typical of this class.

Before the introduction and general use of the separator, a device which separates the cream by centrifugal force from the fresh milk, the dairy breeds represented in the second class were in great demand, because with their milk the cream rose quickly to the surface on standing and was easily skimmed. The skimmed milk, however, of these breeds has the bluish color, familiar to all housewives, and is possessed of small nutritive value. Excessive fat production having been developed at the expense of the food value contained in the whole milk. Moreover, the fat globules are large, being about three times the size of those of the breeds representative of the first class, and hence much more difficult of digestion by children and most invalids.