Report to the Local Government Board upon the "biological properties" of milk, both of the human species, and of cows, considered in special relation to the feeding of infants / by Janet E. Lane-Claypon.
- Lane-Claypon, Janet E.
- Date:
- 1913
Licence: In copyright
Credit: Report to the Local Government Board upon the "biological properties" of milk, both of the human species, and of cows, considered in special relation to the feeding of infants / by Janet E. Lane-Claypon. Source: Wellcome Collection.
80/100 (page 78)
![tile glnnrl the less tlie exudate. It follows, therefore, tliat the traces of such ferments as are found in the milk under normal conditions, are present because they have passed out from the blood either by filtration or exudation. A precisely similar explanation holds good for the presence in milk of substances concerned in the production of immunity. Here also, it has been shown that these bodies which are normally present in the blood are present in increased amounts in the milk at precisely the same periods as those of its increased ferment content, namely, during the production of colostrum or during mastitis; and that when the mammary gland is in full working order little or none of these bodies appears in the milk. Also it the blood passing to the gland contains specific immune substances these substances appear in small quantities in the milk. The mammary gland is not only a secretory organ but also an organ admitting of the passage by filtration or exudation, of traces of the substances which are brought to it in the blood- stream. The value of these materials to the infant evidently depends upon the degree of absorption which takes place from its alimen- tary canal. From the work quoted in Part II. it appears that absorption of protein and hence of the immune substances which are attached to the protein molecule, may take place directly during the first few days of life. This capacity is however of very short duration, especially for foreign protein, which must be broken down before it can be absorbed. The oft-repeated assertion of the value to the infant of raw cows’ milk fades away when the facts are examined, since, in cows’ milk it is found that these so-called “ biological substances are not absorbed in the alimentary canal but are destroyed there. These considerations also explain the results obtained by those who have investigated the comparative nutritive properties of the raw and boiled milk of a foreign species; these results were fully summarised by me in a recent report to the Local Government Board, and it was shown that in dealing with the milk of a foreign species, boiled milk gave perhaps slightly better results than raw milk. In dealing with the milk of a foreign species the real question at issue is that of the chemical clianges which take place on heating. The Berlin figures worked up by me, *and general clinical experience afford conclusive evidence that raising milk to the temperature of boiling water does not destroy oi- apparently injure any of the chemical substances necessary for the health of the child. Above this temperature and even at this temperature for any length of time, chemical changes are known to occur. (In this connection the Addendum to this report may be referred to.) If the milk of the same species be now considered, a somewhat different aspect is put upon the whole question, because there appears to be some degree of evidence that native protein is absorbed as such, for a longer period than foreign ]>rotein. The transitory nature of immunity procured by suckling does not how- ever lead to the supposition that this occurs to any extent, and the](https://iiif.wellcomecollection.org/image/b28143462_0082.jp2/full/800%2C/0/default.jpg)
