ANEMIA 



65 



siderable time for the blood forming organs to make good the sub- 

 stance lost. First, there is a lowering of blood pressure followed 

 by a transfusion of fluids through the capillary walls, partially 

 restoring the volume of fluid in the blood vessels. The composi- 

 tion of the blood is changed. There is a diminished amount of 

 albumins, a diminished number of red corpuscles and an increased 

 amount of salts. Besides the diminution in the number of red 

 corpuscles, morphological changes are found after severe or re- 

 peated hemorrhages. Nucleated red cells may appear within a 

 few hours after rapid hemorrhage. Changes in shape, size and 

 staining are generally seen in from two to four days or more, at 

 the time of greatest reduction in the number of corpuscles. Punc- 

 tate basophilia" and polychromasia are observed with marked 

 oligocythemia. After repeated bleedings in a cow, Smith found 

 20% of the red corpuscles enlarged and 15% showed polychromasia 

 and punctate basophilia. 



Table XIX. — The Following Summary Shows the Effect of Repeated 

 Bleedings on the Red Corpuscles in a Cow (After Smith) 



In small animals the restoration of the volume of blood is rapid 

 while in the larger animals it may be 35-40 minutes (v. Limbeck) 



