SEQUELS OF PARTURITION. 



253 



had been observed in these glands for some time, begins to disappear as 

 they increase in volume, become firmer, tenser, and more sensitive, and 

 receive a larger quantity of blood. Then their activity is suddenly brought 

 into full operation, and their secretion reaches its maximum. At the 

 same time this fluid is modified in quality in a notable but gradual manner, 

 so that it is very different three or four days after parturition from what 

 it was on t^ie first or second day — being colostrum at the early period, 

 and milk subsequently. 



Colostrum. — The first milk, or "colostrum," secreted after delivery is a 

 viscid, dirty-white, or yellowish fluid, sweet, though unpleasant to the 

 taste, and of a greater density than that of ordinary milk, being in the 

 Cow I "063. It is very rich in solid elements, these varying according to 

 individuals, and even breeds. The fat globules are present only in com- 

 paratively small number, and are less in size than in milk at a later period ; 

 l3ut there are numerous colostrum corpuscles — bodies of a large size, 

 spherical or ovoid in shape — of ten agglomerated in masses by a tenacious 

 viscid matter, and among them many leucocytes endowed with movement. 

 Boussingault gives its composition in the Cow as follows : — 



Water 75-8 



Albumen and casein ... 15 'o 



Butter 2-6 



Milk-sugar 3-6 



Salts ...... 3'o 



Dumas gives the colostrum of various animals as below : — 



Water - 

 Fat 



Albumen 

 Mucus - 

 Sugar 



It is admitted that milk is due to a fatty degeneration of the epithelial 

 cells of the gland follicles, in which they are greatly multiplied and 

 developed during lactation. These cells rupture, and nothing remains 

 but the fat globules of the milk. 



Fig. 63. 

 Mammary Gland during Lactation. 

 A, Lobule of the Mammary Gland filled with Cells; B, Milk or Fat Globules; C, Colostrum. 

 a, Ceil filled with Fat Granules and with a visible Nucleus ; b. Cells from which the Nucleus 

 has disappeared. 



But in the colostrum the epithelial cells have not undergone this 

 [change ; their wall is intact, and they still contain their oil granules, 

 ^and consequently constitute the colostrum corpuscles. Colostrum is 



