DISEASES OF HORSES 361 



of the disease in alternate generations, the stallion offspring of blind 

 parents remaining sound through life and yet producing foals which 

 furnish numerous victims of recurrent ophthalmia. On the con- 

 trary, the offspring of diseased parents removed to high, dry regions 

 and furnished with wholesome, nourishing rations will nearly all 

 escape. 



Yet the hereditary taint is so strong and pernicious that intelli- 

 gent horsemen everywhere refuse to breed from either horse or mare 

 that has once suffered from recurrent ophthalmia, and the French 

 Government studs not only reject all unsound stallions, but refuse 

 service to any mare which has suffered with her eyes. It is this 

 avoidance of the hereditary predisposition more than anything else 

 that has reduced the formerly wide prevalence of this disease in the 

 European countries generally. A consideration for the future of 

 our horses would demand the disuse of all sires that are unlicensed, 

 and the refusal of a license to any sire which has suffered from this 

 or any other communicable constitutional disease. 



Other contributing causes deserve passing mention. Unwhole- 

 some food and a faulty method of feeding undoubtedly predisposes 

 to the disease, and in the same district the carefully fed will escape 

 in far larger proportion than the badly fed. But it is so with every 

 other condition which undermines the general health. The presence 

 of worms in the intestines, overwork, and debilitating diseases and 

 causes of every kind weaken the vitality and lay the system more 

 open to attack. Thierry long ago showed that the improvement of 

 close, low, dark, damp stables, where the disease had previously pre- 

 vailed, practically banished this affection. Whatever contributes to 

 strength and vigor is protective; whatever contributes to weakness 

 and poor health is provocative of the disease in the predisposed 

 subject. 



Symptoms. The symptoms vary according to the severity of 

 the attack. In some cases there is marked fever, and in some 

 slighter cases this may be almost altogether wanting, but there is 

 always a lack of vigor and energy, bespeaking general disorder. 

 The local symptoms are in the main those of internal ophthalmia, 

 with, in many cases, an increased hardness of the eyeball from 

 effusion into its cavity. The contracted pupil does not expand much 

 in darkness, nor even under the action of belladonna. Opacity ad- 

 vances from the margin, over a part or whole of the cornea, but so 

 long as it is transparent there may be seen the turbid, aqueous humor 

 with or without flocctili, the dingy iris robbed of its clear black 

 aspect, the slightly clouded lens and a greenish yellow reflection 

 from the depth of the eye. From the fifth to the seventh day the 

 flocculi precipitate in the lower part of the chamber, exposing more 

 clearly the iris and lens, and absorption commences, so that the 

 eye may be cleared up in ten or fifteen days. 



The characteristic of the disease is, however, its recurrence again 

 and again in the same eye until blindness results. The attacks may 

 follow each other at intervals of a month, more or less, but they show 



