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.

Janet Lane-Claypon

Date:: 1913

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.

35/100 (page 33)

$F.M.B. being’ decolourised in about 10 minutes at 65-70° C. When the reaction is just beginning’ to appear in the early stages of lactation then a better reaction may sometimes be obtained at 45° C. He also showed that serum has a well marked inhibitory ehect upon the reaction. The serum of many animals was examined and the same result obtained with them all. In this connection it may be mentioned that Gift'horn(®^) in 1911 showed that if F.M.B. was decolourised with very great rapidity in fresh milk the milk will have come from a diseased udder, which also agrees with Koning’s observations. Trommsdorlf(^^*^) (1909) obtained milk direct from the cow’s udder by means of a milking tube. By taking the most stringent precautions against contamination he was able to obtain milk which, on plating out, was found to be sterile. This milk was tested for the presence of Schardinger’s reaction and the result was positive. Hence it seems certain that milk which has never been contaminated by bacteria does contain a substance capable of reducing methylene blue in the presence of formaldehyde. Trommsdorlf found that the acidity of the milk rose during the course of the reaction, and concluded that this was due to the formation of formic acid from the formalin. He found, however, that the acidity rose in precisely the same manner, whether formalin was added or not, so that it was not due to the production of formic acid. Kooper(®^) (1910) endeavoured to show that the F.M.B. re- action was bacterial in origin. He took milk soon after milking and on the two following days, and using Schardinger’s reagent only, found that the reduction time was shortened as the days passed, and that boiled milk regained its reducing power if small quantities of raw milk were added to it. The same remarks apply here which have already been made in regard to Seligmann’s work, and it need not be further dwelt upon {see p. 30). Sames(^'^“) (1910) working alone and also in conjunction with Rbmer(^'^^) brought out many points in connection with this reaction. They investigated the reducing power of the different portions of milk as it leaves the udder. They found, as had in part been done by previous observers, that the first milk very rarely reduced at all, and then only in- completely. Middle milk varied a great deal in its reducing power, and did not always reduce completely; whilst tlie strip- pings always reduced very rapidly, never taking longer that 84 minutes. The various constituents of the three different portions of milk were then most carefully investigated, and it was found that the only constituent which varied markedly in quantity in the different portions was the fat, the content of which was very appreciably higher in the strippings than in the rest of the milk. There was, however, no constant parallelism between the rate of reduction and the percentage of fat. If the cows were kept waiting long between the ])eriods of milking then the reaction was often negative. 26403 0$