DISEASES OF HORSES 95 



In cases attended with complications, the diagnosis becomes at 

 times still more difficult, as at the end of a case of influenza which 

 becomes complicated with pneumonia. The high temperature of 

 the simple inflammatory disease may be grafted on that of the spe- 

 cific trouble, and the determination of the cause of the fever, as be- 

 tween the two, is therefore frequently a difficult matter but an im- 

 portant one, as upon it depends the mode of treatment. 



Any animal suffering from fever, whatever the cause, is much 

 more susceptible to attacks of local inflammation, which become 

 complications of the original disease, than are animals in sound 

 health. In fever we have the tissues and the walls of the blood ves- 

 sels weakened, we have an increased current of more or less altered 

 blood, flowing through the vessels and stagnating in the capillaries, 

 which need but an exciting cause to transform the passive conges- 

 tion of fever into an active congestion and acute inflammation. 

 These conditions become still more distinct when the fever is accom- 

 panied by a decided deterioration in the blood itself, as is seen in 

 influenza, septicemia, and at the termination of severe pneumonias. 



Fever, with its symptoms of increased temperature, accelera- 

 tion of the pulse, acceleration of respiration, dry skin, diminished 

 secretions, etc., must be considered as an indication of organic dis- 

 turbance. This organic disturbance may be the result of local in- 

 flammation or other irritants acting through the nerves on nerve 

 centers ; alterations of the blood, in which a poison is carried to the 

 nerve centers, or direct irritants to the nerve centers themselves, as 

 in cases of heat stroke, injury to the brain, etc. 



The treatment of fever depends upon its cause. One of the im- 

 portant factors in treatment is absolute quiet. This may be obtained 

 by placing a sick horse in a box stall, away from other animals and 

 extraneous noises, and sheltered from excessive light and drafts of 

 air. Anodynes, belladonna, hyoscyamus, and opium act as antipy- 

 retics simply by quieting the nervous system. As an irritant ex- 

 ists in the blood in most cases of fever, any remedy which will favor 

 the excretion of foreign elements from it will diminish this cause. 

 We therefore employ diaphoretics to stimulate the sweat and excre- 

 tions from the skin ; diuretics to favor the elimination of matter by 

 the kidneys ; cholagogues and laxatives to increase the action of the 

 liver and intestines, and to drain from these important organs all 

 the waste material which is aiding to choke up and congest their 

 rich plexuses of blood vessels. The heart becomes stimulated to in- 

 creased action at the outset of a fever, but this does not indicate 

 increased strength ; on the contrary, it indicates the action of an ir- 

 ritant to the heart that will soon weaken it. It is therefore irrational 

 to further depress the heart by the use of such drugs as aconite. It 

 is better to strengthen the heart and to favor the elimination of the 

 substance that is irritating it. The increased blood pressure through- 

 out the body may be diminished by lessening the quantity of blood. 

 This is obtained in some cases with advantage where the disease is 

 but starting and the animal is plethoric by direct abstraction of 

 blood, as in bleeding from the jugular or other veins ; or by deriva- 



