128 NON-SPECIFIC OR GENERAL DISEASES 



niation. It is necessary to confine the animal in some way before 

 attempting to do this. Horses should be twitched, cattle held by 

 the nose, and the- head of a small animal held firmly with the 

 hands. It may be necessary to cocainize the eye before the oper- 

 ator can remove the foreign object with absorbent cotton or with 

 forceps. 



In case of injuries and irritation to the lids by foreign bodies, 

 the eye may be flooded with a three per cent water solution of 

 boric acid twice daily, or as often as necessary. Such washes or 

 lotions may be applied with a small piece of absorbent cotton, 

 using a fresh piece each time the eye is dressed. A medicine 

 dropper may also be used. A lotion containing silver nitrate 

 two to four grains and distilled water one ounce, is useful in 

 combating the inflammation. This may be applied twice daily. 

 Irritating lotions should be avoided, if possible, in the treat- 

 ment of eye diseases of horses, because of the danger of making 

 the animal disagreeable to handle. Boric acid may be dusted 

 over the ball of the eye of cattle with a powder blower. 



Periodic Ophthalmia, " Moonblindness." — This is a peri- 

 odic inflammation of one or both eyes of the horse. The internal 

 structures of the eye are involved by the inflammation, but it 

 may appear as a conjunctivitis. 



The cause of this disease is not well understood. Certain 

 local conditions seem to favor its development. Undrained land, 

 a humid climate, the feeding of a one-sided ration or one that 

 does not maintain the vitality of the animal, and severe work 

 seem to produce it. Heredity must be accepted as a prominent 

 accessory cause. A number of diflerent bacteria have been 

 mentioned as causative factors for this disease. 



The symptoms at the very beginning indicate a general in- 

 flammation of the eye. The eyelids are swollen, there is an 

 abundant secretion of tears, the eyeball is retracted and the lids 

 are held more or less closed. As the inflammation progresses, 

 the cornea becomes milky in appearance and the aqueous humor 



