55 Internal Influences on the Character of Milk. 



fat in colostrum, as compared with ripe milk, the amount of dry substances in colos- 

 tral milk is very high, and its specific gravity is increased. The amount of urea, cre- 

 atinin, cholesterin, and lecithin in colostrum is increased. The milk at this stage is 

 rich in fat-containing glandular epithelium in the form of foam cells, and seal-ring- 

 shaped cells with so-called caps and moons, and in albuminophores. Numerous leuco- 

 cytes are to be found, and during the first days red blood corpuscles are also present 

 in great numbers. According to Emmerling, cow colostrum, on the rnorning after the 

 birth of the calf, consists of 76.14% of water, and 23.86% of dry substance, of which 

 4.705% is casein, 0.58 albumen, 8.320 globulin. Compared with normal milk, the fat 

 content is increased or diminished, the milk sugar diminished, and the ash contents 

 increased. 



Engling found the following values for colostrum: 



Immediately after After 10 After 24 After 48 After 72 



calving hours hours hours hours 



Specific gravity 1.068 1.046 1.043 1.042 1.035 



Solids 26.83 21.23 19.37 14.19 13.36 



Casein 2.65 4.28 4.5 3.25 3.33 



Albumin and globulin 16.56 9.32 6.25 2.31 1.03 



Fat 3.53 4.66 4.75 4.21 4.8 



Milk sugar 3.0 1.42 2.85 3.46 4.1 



Ash 1.18 1.55 1.02 0.96 0.82 



The composition of the ash differs from that of ripe milk, as may be observed 

 from the findings of Schrodt and Hansen: 



Ripe Milk (10 days 

 Colostrum after calving) 



17.4 24.12 



10.10 8.72 



22.99 22.69 



6.88 2.92 



0.42 Traces 



2.82 4.10 



34.30 30.73 



6.85 8.30 



The ferments in colostrum also deserve special consideration. 

 The amylase content is considerably increased, also the amount 

 of catalase. During the colostral period the milk further con- 

 tains hemolytic amboceptors and increased complement. Formalin 

 methylene blue is not decolorized. The reaction of the colostrum 

 is acid. 



The colostral period lasts from 3 to 5 days after calving. In 

 heifers the transition period results more slowly than in old cows 

 (Deisman, Hittcher). Up to the end of this period there is a 

 constantly increasing approach to the properties of ripe milk r 

 together with an increase in the yield, which continues to increase 

 until the first or second month, and then gradually recedes and 

 finally rapidly diminishes towards the end of the lactation period. 

 The reduction of the milk yield corresponds with an increase in 

 the percentage of fat. The fat globules become smaller and more 

 numerous. At the end of the lactation period the milk again 

 assumes the character of colostrum, becoming especially rich in 

 chlorine, and sodium oxide, while the phosphoric acid and the 

 potassium contents appear diminished. The milk becomes salty, 

 bitter, and its reaction alkaline. The entire time of lactation or 

 one lactation period, usually lies between the birth of two calves, 



