51 



lakes. The digestive tract may become infected with these 

 parasites by iugesting infected food. In all cases where 

 parasites are found in the alimentary canal (manifested by 

 the occasional passing of parasites with the feces), it is ad- 

 visable to give one-half to one drachm doses of sulphate of 

 iron or sulphate of copper in the ground food two times per 

 day for one week; then give a purgative, consisting of one 

 pint of raw linseed oil or one ounce of Barbadoes aloes. 



STRABISMUS, SQUINTING OR CROSSEYE. 



In this defect the visual axis or line of one or both eyes 

 deviates from the normal. In other words, the eye ball is 

 turned inward, outward, upward or downward by the exces- 

 sive contraction of a muscle or as a result of the paralysis 

 of one of the muscles of the eye. In converging (inward) 

 strabismus, the external rectus muscle may be paralysed and 

 thus be unable to counteract the contractions of the internal 

 rectus, its antagonist. This weakness, partial or complete 

 paralysis of one or more muscles of the eye may be due to 

 the pressure of tumors on the nerve of the muscle, rheuma- 

 tism, tumors at the base of the brain or injuries of the 

 muscle. Squinting or crosseye may be treated by section 

 of the antagonistic muscle, but this can be doue only by a 

 skilled veterinarian. However this defect is rare in domestic 

 animals aud may be detected by noting the squinting ap- 

 pearance and carefully comparing one eye with the other. 

 When strabismus is present it causes considerable shying, 

 which is especially annoying in nervous animals. 



SOME OF THE CAUSES OF INDISTINCT VISION 



AND SHYING. 



Hypermeiropia or farsightedness is that defective condi- 

 tion of the eye which causes the principal focus to fall be- 



