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causes, but in influenza the local symptoms are frequently masked or 

 even entirely hidden hy the intense stupor of the animal, which ren- 

 ders it insensible to pain. The evidence of colic and congestion, 

 which is followed by diarrhea, fills the symptoms for the diagnosis of 

 enteritis. The rapid breathing or difiiculty of respiration forms the 

 suspicion at once of complication of the lungs, but as we have seen in 

 the study of the sj-mptoms the local evidences of lung lesions are fre- 

 quently hidden. Again, we have seen that inflammation of the feet 

 or founder complicating influenza is frequently not shown on account of 

 the insensibility to pain on the part of the animal, which indicates the 

 importance of running the hand daily over the hoofs to detect any 

 sudden elevation of temperature on their surface. 



The diagnosis of brain trouble is based upon the excessive violence 

 which occurs in the course of the disease, for during the intervening 

 period or coma there is no means of determining that it is due to this 

 complication. Severe cases of influenza may simulate anthrax in the 

 horse. In both we have stupor, the intense coloration of the mucous 

 membranes of the eyes and a certain amount of swelling of the legs 

 and under surface of the belly. The diagnosis here can only be made 

 by microscopic examination of the blood. In strangles, equine variola, 

 and sealma we have an intense red, rosy coloration of the mucous 

 membranes, full, tense pulse, and although in these diseases we may 

 have depression, we do not have the stupor and coma, except in severe 

 cases which have lasted for some days. In influenza we have no evi- 

 dence of the formation of j)us on the mucous membranes as we did 

 in the other diseases, except in the conjunctiva of the eyes, where, 

 however, we have had a profuse serous discharge, producing the 

 conjunctivitis. 



In severe x)neumonia (lung fever) Ave may have profound coma, 

 dark yellowish coloration of the mucous membranes, and swelling of 

 the under surface of the belly and legs, but in pneumonia we have the 

 history of the difiicultj^ of breathing and an a<?ute fever of a sthenic 

 tyj)e from the outset, and the other sj'mptoms do not occur for several 

 days; while in influenza we have the history of characteristic symp- 

 toms for several days before the rapid breathing and difficult}- of res- 

 pii-ation indicate the appearance of the complication. Without the 

 history it is frequently difficult to diagnose a case of influenza of 

 scA'eral days' standing complicated by pneumonia from a case of severe 

 pneumonia of five to six days' standing, but from a prognostic point 

 of view it is immaterial, as the treatment of both are identical. 



Prognosis. — Influenza Is an excessivelj^ serious disease for many 

 reasons. We find the majority of horses susceptible to this virus when 

 exposed to it. It is fatal to a large number of animals even vvith the 

 best treatment, and is especially fatal to the young and to those ani- 

 mals which are more valuable from their fine breeding, as the disease 

 occurs in a more serious form in well-bred animals than it does in the 



