360 DISEASES OF CATTLE. 



circumstances the fungoid mass must be cut away, and the v/ound 

 cauterized with the nitrate of silver, or else the eye will soon be 

 destroyed. When ulcers of the cornea apj^ear indolent, with a tend- 

 ency to slough, in addition to the treatment already prescribed, tonic 

 powders should be given twice a day mixed with the feed ; powdered 

 copperas, gentian, and ginger, equal parts by weight. Dose, one 

 tablespoonful. 



STAPHYLOMA. 



This is a disease of the eyeball, in which the cornea loses its trans- 

 parency, rises above the level of the eye, and even projects beyond the 

 eyelids in the form of an elongated, whitish, or pearl-colored tumor, 

 which is sometimes smooth, at other times uneven. 



Causes. — Inflammation is the only known cause, although it may 

 not occur immediately; it frequently follows catarrhal conjunctivitis 

 and keratitis as a sequela. 



Treatme'iit. — In a few cases restoration of sight may be effected by 

 puncturing the projecting tiunor. and treating it afterwards with 

 nitrate of silver in the same manner as prescribed for ulceration of 

 the cornea. In some cases spontaneous rupture has occurred, and 

 healing without any treatment at all. 



CATARACT. 



In cataract the crystalline lens becomes opaque and loses its trans- 

 parency, the power of refraction is lost — the animal can not see. 



Causes. — Cataract generally arises from a diminution (atrophy) or 

 other change in the nutrition of the lens; it may occur as a result 

 of inflammation of the deep structures of the eye. Cataract may be 

 simple, or complicated with amaurosis, adhesions, etc. 



Syonptom-s. — It is known by the whiteness or loss of transparency 

 of the lens, although the pupil dilates and contracts. Sight may be 

 totally lost ; however, evidence is usually manifested that the.animal 

 distinguishes light when brought out of a darkened stable. For the 

 most part the formation of cataract takes place slowly, the cases in 

 which it originates very quickly being but few. 



Treatment. — There is only one method for the treatment of cata- 

 ract — a surgical operation for the removal of the lens ; but this is not 

 advisable, for the sight can not be perfectly restored, and objects 

 would be seen imperfectly without the aid of glasses. 



AMAUROSIS. 



A paralysis of the nerve of sight or the expansion of the retina. 

 Causes. — This is the result of concussion from a blow upon the 

 forehead, fracture of bone over the eye (causing downward pressure). 



