1290 



PHYSIOLOGY 



is obtained from the breast is known as colostrum. It may be expressed 

 from the breasts immediately after birth and is ingested by the child during 

 the first two days after birth. The colostrum is formed only in slight 

 quantities. It is an opalescent fluid, often somewhat yellowish, containing 

 fat globules which, if the fluid be allowed to stand, form a yellowish layer 

 on the top. Under the microscope, in addition to the fat globules, may be 

 seen the so-called colostrum corpuscles, which consist of multinucleated cells 

 loaded with particles of fat. They are probably leucocytes or phagocytes 

 which have wandered into the alveoli and have taken up fat globules. Some 

 of the corpuscles may be desquamated secretory cells. Colostrum is distin- 

 guished from true milk by containing little or no caseinogen. It contains 

 about 3 per cent, of proteins, namely, lactalbumen and lactoglobulin, which 

 coagulate on boiling. Lactose and salts are present in the same proportions 

 as in ordinary milk. It is popularly supposed to have a laxative effect 

 on the child. 



TABLE SHOWING AMOUNT OF MILK SECRETED BY A NURSING WOMAN. 



INCREASE 



Time 

 1st day 

 2nd 

 3rd 

 4th 

 5th 

 6th 

 7th 



2nd week . 

 3rd^th week 

 5th-8th 

 9th-12th 

 13th-16th 

 17th-20th. 

 21st-24th 

 25th-28th 



Milk secreted 

 20 grm. 

 97 



211 



326 



364 



402 



478 



502 



572 



736 



797 



836 



867 



944 



963 



DECREASE 



29th-32nd week 

 33rd-36th 

 37th week 



916 grm. 

 909 



885 



PROPERTIES OF MILK 



Fully formed milk presents certain features which are common to all 

 mammals. These have been chiefly studied in the case of cows' milk. We 

 may therefore deal with the composition of cows' milk and point out .later 

 in what respects human milk differs therefrom. Milk is an opaque white 

 fluid with characteristic odour and sweetish taste. Its specific gravity 

 varies between 1028 and 1034. Its reaction to litmus is neutral, to lacmoid 



