146 THB HORSE. 



one succeeding the other. To fever as a disea.se is usually added chills 

 as an essential symptom. 



Whether the cause of the fever has been an injury to the tissues, 

 as a severe bruise, a broken bone, an inflamed lung, or excessive 

 work which has surcharged the blood with the waste products of 

 the combustion of the tissues, which were destroyed by produce force; 

 or the puUulation of the ferments of influenza in the blood which 

 destroy the red blood corpuscles; or the presence of irritating mate- 

 rial, either in the form of living organisms or of their products, 

 as in glanders or tuberculosis, the general train of symptoms are the 

 same, only varying as the amount of the irritant differs in quantity, or 

 when some special quality in them has the specific action on one or an- 

 other tissue. 



There is in fever at first a relaxation of the small blood ves- 

 sels, which may have been preceded by a contraction of the same 

 if there was a chill, and as a consequence there is an acceleration 

 of the current of the blood. There is then an elevation of the per- 

 ipheral temperature, followed by a lowering of tension in the ar- 

 teries and an acceleration in the movement of the heart. These con- 

 ditions may be produced by a primary irritation of the nerve centers, 

 or the brain from the effects of heat, as is seen in thermic fever or 

 sunstroke, in which trouble the extremes of symptoms may some- 

 times be seen alternating with a very short period, to be counted scarcely 

 by hours. 



There are times when it is difficult to distinguish between the exist- 

 ence of fever as a disease and a temporary feverish condition which is 

 the result of excessive work. Like the condition of congestion of the 

 lungs, which is normal up to a certain degree in the lungs of a race 

 horse after a severe race, and morbid when it produces more than 

 temporary phenomena or when it causes distinct lesions, fever, or as 

 it is better termed a feverish condition, may follow any work or other 

 employment of energy in which excessive tissue change has taken 

 place, but if the consequences are ephemeral, and no recognizable lesion 

 is apparent, it is not considered morbid. This condition, however, may 

 predispose to severe organic disturbance and local inflammations which 

 will cause disease, as an animal in this condition is liable to take 

 cold, develop a lung fever or a severe enteritis, if chilled or otiier- 

 wise exposed. 



Fever in all animals is characterized by the game general ohenomena. 



