EPIZOOTIC KERATITIS 19 



cure than when it involves other soft structures, even 

 more stubborn to treat than some of the cases where 

 osseous tissue is extensively involved. The treatment 

 is the same as that for involvement of other organs 

 and tissues. 



EPIZOOTIC KERATITIS 



This is a disease affecting the eyes of cattle which 

 occurs from time to time in certain localities. It is 

 seen usually during the summer months w^hen the cat- 

 tle are on grass. Almost without exception it attacks 

 every animal in a herd of cattle w^hich it invades. In 

 rare instances a few animals may escape the infection. 



The first attacked in an outbreak usually develop 

 the disease in its most severe form; towards the latter 

 part of the epizootic the cases become milder and may 

 recover spontaneously. 



The disease affects cattle only. Horses in the same 

 pastures with the affected cattle do not develop the 

 disease, nor are other animals on the farm affected. 

 We recall an instance where a man, who had a herd 

 of cows under his care during an outbreak of keratitis 

 and who treated the eyes of those affected, contracted 

 a mild conjunctivitis. 



In the mild or sub-acute form the symptoms are con- 

 fined wholly to the eyes. In the severe form the ani- 

 mal shows systemic derangement such as loss of appe- 

 tite and a considerable interference with the lacteal 

 secretion. 



The first symptom, that the farmer sees, when the 

 disease appears in his herd is lachrymation. When the 

 cows are brought in from pasture at night he notices 

 a few cows with ''a running from the eyes.'' The 



