DISEASES OF THE CIRCULATORY ORGANS 105 



The functions of the blood arc to nourish the body tissues; 

 furnish material for the purpose of the body secretions ; supply 

 the cells of the body with oxygen; convey from the tissues 

 injurious substances produced by the cellular activity; and 

 destroy organisms that may have entered the body tissues. The 

 cellular and fluid portions of the blood are not always destruc- 

 tive to disease-producing organisms. In certain infectious dis- 

 eases, the fluid portion of the blood may contain innumerable 

 organisms, and destruction of the blood cells occurs. 



In inflammation of tissue the circulation of the blood in 

 the inflamed part undergoes certain characteristic changes. At 

 the beginning there is an increase in the blood going to the part. 

 This is followed by a slowing of the blood stream in the small 

 vessels, and the collecting of the blood cells in the capillaries 

 and veins. These circulatory changes are followed by the migTa- 

 tion of the blood cells, and the escape of the fluid portion of the 

 blood into the surrounding tissue. The character of the above 

 circulatory changes depends on the extent of the injury to the 

 tissue. 



Palpitation. — This disturbance in domestic animals seems to 

 be purely functional. It may occur independent of any organic 

 heart disease. A highly nervous condition, excitement, over- 

 exertion, debility from disease and the feeding of an improper 

 ration are the common causes. 



The heart beats are so violent and tumultuous as to shake 

 the body, and be noticed when standing near the animal. 

 The heart sounds are louder than normal and the pulse beats 

 small and irregular. It may be differentiated from spasm of 

 the diaphragm by determining the relationship of the heart 

 beats to the alirupt shocks observed in the costal and flank 

 regions. 



The treatment consists in keeping the animal quiet and 

 avoiding any excitement. A quiet stall away from the other 

 animals is best. The treatment of palpitation resulting from 



