420 IOWA DEPARTMENT OF AGRICULTURE 
iiish numerous victims of recurrent ophthalmia. On the contrary, the 
offspring of diseased parents removed to high, dry regions and furnished 
with wholesome, nourishing rations will nearly all escape. Hence the 
dealers take colts that are still sound or have had but one attack from 
the affected low Pyrenees (France) to the unaffected Catalonia (Spain), 
with confidence that they will escape, and from the Jura Valley to Dau- 
phiny with the same result. 
Yet the hereditary taint is so strong and pOTnicious that intelligent 
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 heredi- 
tary 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. Unwholesome 
food and a faulty method of feeding undoubtedly predisposes to the dis- 
ease, 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 in- 
testines, 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 prevailed, practically banished this af- 
fection. Whatever contributes to strength and vigor is protective; what- 
ever contributes to weakness and poor health is provocative of the dis- 
ease in the predisposed subject. 
Symptoms. — The symptoms vary according to the severity of the at- 
tack. 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 advances from the margin, over a part or whole of 
the cornea, but so long as it is transparent there may be seen th6 turbid, 
aqueous humor with or without flocculi, 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 no rela- 
tion to any particular phase of the moon as might be inferred from the 
familiar name, but are determined rather by the weather, the health, the 
