42 MILK AND ITS HYGIENIC RELATIONS 



of colostrum was essentially a whey-protein anti-serum, owing 

 to the predominance in the colostrum of these proteins. 



Kollmeyer and Bauer and Engel all agree as to the marked 

 relative increase in the albumin-globulin bodies in colostrum 

 as compared with later milk. 



Langer (1907) obtained a more powerful anti-serum by injecting 

 colostrum than by using later milk. He does not appear to have 

 distinguished between the different antigens in colostrum, but his 

 observations can be explained by the work of the above authors. 

 Konig's figures for the protein content of colostrum, given on p. 16, 

 are of much interest in connection with the investigations just 

 quoted. 



The value of colostrum from the nutritive standpoint has 

 already been considered, and its importance in the question of 

 immunity will be considered in Chap. VI. 



Some experiments have also been carried out in order to ascer- 

 tain the effect (if any) of heat upon the power of the milk protein 

 to produce anti-sera and anaphylaxis. These are dealt with in 

 Chap. XIV. 



Wroblewski described another protein in cows' milk which he 

 termed 'opalisin.' The presence of this body has, however, not 

 been confirmed, and is denied by Eufinger. 



Meigs and Marsh described a further nitrogenous body in 

 milk, but this also has not been confirmed. 



Some non-protein nitrogen undoubtedly occurs in milk, and 

 its nature has been studied by several observers. Rietschel believes 

 that urea accounts for the bulk of the non-protein nitrogen. 



An isolated observation and of interest has been made by Engel 

 and Murschhauser (1,2). These observers found that urea appeared 

 in the milk of an eclamptic woman. They subsequently succeeded 

 in obtaining evidence of a rise of non-protein nitrogen in the milk 

 of a healthy woman, who was fed on considerable amounts of urea. 

 They suggest that the mammary gland may have a slight excretory 

 function when waste material is present in excess in the blood. 



Fat. It has been shown in the preceding pages that no precise 

 figure can be given for the fat content of milk. Even when a 

 sample of the whole milk obtained at one time is taken, the figure 

 holds only for that particular occasion. 



The work both of Hunnaeus and of Aurnhammer on human 

 milk shows that considerable individual differences in the average 

 amount of fat given in twenty-four hours may occur. Hunnaeus 

 says the figure varies from 4 per cent, to 5 per cent, for the twenty- 

 four hours, and Aurnhammer gives 4*5 per cent, to 5-5 per cent., 

 but these are averages only, the actual figures showing a greater 

 range. 



Aurnhammer finds that the total amount of fat given in the 

 twenty-four hours by each individual is fairly constant, and that 

 it does not increase with an increase in the amount of milk given. 



