110 The Diseases of Animals 



trols the whole body, making the different parts act in 

 harmony. It enables the animal to comprehend what 

 is going on around him, and to regulate his own activ- 

 ities. The brain, spinal cord and nerves, together with 

 small masses of nervous tissue known as ganglia, con- 

 stitute the nervous system. 



When all of these different systems and parts of 

 the body are complete and in their normal working 

 order, the animal is said to be in a state of health. 

 But when some parts of the body are injured, or their 

 work is in any way interfered with, an abnormal con- 

 dition occurs to which the term "disease" is applied. 



It is essential that the observer be familiar with the 

 actions of the animal, not only in a state of health, but 

 also in disease, since it is by comparison of these two 

 conditions that disease is recognized. Signs of disease 

 are commonly known as "symptoms." The study of these 

 symptoms and the recognition of their causes is called 

 "diagnosing the disease," or "diagnosis." The expression 

 of an opinion as to the probable future course of the 

 disease is called "prognosis," and, if favorable, indicates 

 that the observer believes that the animal will recover; 

 if unfavorable, that it will not. The following points 

 are be particularly noted in examining sick animals. 



PULSE 



The pulse is the throbbing of an artery. By it is 

 determined the heart's action and also the condition of 

 the nervous system. In the horse, the pulse is usually 

 taken where the submaxillary artery winds under the 



