INFLUENZA. 451 



The MORTALITY among properly treated cases, will not exceed 

 3 per cent, as a rule. 



SYMPTOMS. — The distinguishing characteristics of influenza are 

 the suddenness of its attack, its widely^distributed nature, and the 

 debility, depression, and rise in internal temperature (to 104°, or 

 even to 105° F.) which accompany its onset. Simple catarrhal 

 influenza, besides these characteristics, has little to distinguish it 

 from nasal catarrh (p. 367). In ordinary pink-eye, catarrhal 

 symptoms are, usually, not well marked. An attack is not in- 

 frequently preceded by colicky pains. There is considerable rise of 

 the internal temperature, which may be observed, at least, twenty- 

 four hours before the manifestation of the symptoms ; great 

 debility ; stiffness of the limbs and body at first ; weak, frequent 

 pulse; and a pink appearance of the inside of the eyelids. There 

 is great dulness; in fact, the animal is in a more or less uncon- 

 scious state. As a rule, the eyelids swell, and tears flow from the 

 eyes. Constipation is generally present ; although those cases in 

 which spontaneous diarrhoea or profuse staling occurs, recover far 

 more rapidly than the others. The stiffness of the limbs is usually 

 followed by swelling of those parts, and consequent disappearance 

 of pain. Sometimes, there is great lameness as if from inflamma- 

 tion of the feet (laminitis, p. 184). Occasionally, cough and sore- 

 ness of the throat are present. Symptoms of inflammation of the 

 lungs may also appear. 



The great danger to be dreaded in pink-eye is the formation of 

 clots in the blood-vessels. In fact, a horse which was previously 

 doing well to all appearsuice, may often die suddenly on acocJunt 

 of the existence of a clot of blood in the heart. In the living 

 healthy body, blood always remains fluid ; but when the vitality 

 of the system is lowered, the constituents of a clot (p. 12), which 

 were previously held apart, tend to unite. As debility of the 

 heart, a prominent feature of this disease, is one of the chief causes 

 that induce coagulation of blood in the vessels, efforts should be 

 directed to maintain the strength of this organ, as well as to 

 preserve the fluidity of the blood. It is almost needless to say 

 that the more insanitary and damp a stable is, the more liable, 

 during an outbreak, will horses in it be to an attack of influenza, 

 and the less able will they be to combat the evil effect of the 

 disease. 



Bowel complications, when present, usually appear along with 

 the catarrhal symptoms, or may follow them. There is more or 

 less continued abdominal pain. The mucous membrane of the 

 eyelids is, generally, of a bilious red colour; and the pulse 

 frequent and wiry. Blood-spots (p. 501) have been observed on 



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