32 MILK AND ITS HYGIENIC RELATIONS 



The principle of the method of complement deviation is some- 

 what elaborate and more sensitive. It has been used mainly by 

 Bauer working alone and with Engel. These authors have con- 

 firmed and extended the results obtained by the precipitin methods. 

 Further, it has been shown (i) that both human and cows' milk 

 contain lacto-globulin, more being present in human milk than in 

 cows' milk. Although present only in small amounts, this body 

 acts as a powerful exciter of reactions when injected into the body. 



(2) That the albumin and the globulin in the milk of both species 

 are biologically identical with those bodies in the blood of that 

 species. 



(3) That albumin and globulin are more closely related to one 

 another than to caseinogen. 



(4) That caseinogen is, however, more closely related to globulin 

 than to albumin. 



Confirmatory although less extensive results have been obtained 

 by the third method, that of anaphylaxis. 



The Proteins of Colostrum. The protein content of colostrum is 

 higher than that of the later milk. The above methods have 

 been used to show that the proteins of colostrum and of later milk 

 are identical, and that the albumin and globulin of milk are identical 

 with these bodies in the blood. There is some uncertainty as to 

 whether the caseinogen or the whey-protein (albumin and globulin) 

 predominates. Probably both are present in greater amount than 

 in later milk, but the whey-protein is further increased relatively to 

 the caseinogen. 



The identity of the proteins of the blood and of whey, which has 

 been shown by the above methods, raises important questions. It 

 is difficult to avoid the conclusion that the proteins of whey are 

 derived directly from the blood by filtration. Caseinogen, however, 

 must be formed by the gland, either by a modification of the blood- 

 protein or it must be derived from the gland cells. 



Bauereisen points out, and this has also been shown by other 

 authors, that we must regard the colostral period as being the 

 transition stage for the infant from that period when it was nourished 

 directly by the blood of its mother, to the subsequent period when 

 it depends upon its own alimentary tract for nourishment. The 

 protein constituents of whey and of blood are practically identical : 

 the method of administration constitutes the main difference. In 

 the transition period, extending immediately after birth up to the 

 end of the colostral period, that is, probably until about the fourth 

 or fifth day (when the colostral characteristics cease to be marked), 

 a different mechanism of absorption appears to be employed by 

 nature. This method has for its object the tiding over of the 

 infant from the intrauterine period to the period when it is dependent 

 upon its own digestive juices, and it seems that the proteins of the 

 colostrum can be absorbed by the infant from its alimentary canal 

 without undergoing any marked changes, whereas later, after the 



