Proteins of the Whey Fraction in Milk from Normal and Abnormal Udders

It is known that during normal lactation milk contains relatively constant quantities of protein. The bulk of the protein constituents is made up of casein but when this is precipitated by rennet or weak acids there remain in the whey small quantities of other proteins. These make up, according to Vun Slyke (1), about 0.8 to 1.0 per cent of the total solids of milk. The proteins of whey have been obtained in a high degree of purity by OSborne and Wakemen (2) who designate 3 types, lactalbumin, lactoglobulin, and an alcohol soluble protein. Both by chemical and immunological methGds Crowther and Rastrick (3), and Wells and Osborne (4) have shown that the lactogtobulin cannot be differentiated from the blood globulin although blood albumin differs from lactalbumin. Analyses of whey proteins, as usually given, are--albumin, six rags. per cc. ; globulin, two rags. per cc. (Van Slyke, 1). J.ones (5) was able to show that milk from normal cows, probably because of its globulin content, reacted at definite levels with a cow serum precipitin and that when the udder became inflamed smaller quantities of milk reacted with the blood serum precipitin, indicating increased blood serum antigens in the milk.