PARASITIC DISEASE IN HORSES. 
205 
a rule structurally weak, and incapable of great exertion. 
They are also subject to many diseases ; are particularly liable 
to be infested with parasites, and to fall a prey to the effects 
which they produce on the system. 
If these remarks be true ; prevention, as far as our climate 
will admit, is to a certain extent in the hands of the breeder; 
and there can be no doubt, I think, but that the best localities 
for breeding and rearing horses are good, dry, upland pas¬ 
tures, covered with short but nutritious grasses, having the 
surface undulating, and not too highly wooded. Care also 
should be taken in providing suitable winter provender. The 
hay, especially, should be well cured, and the produce of good 
sound land. Bad provender is well known to be favorable 
to the engendering of parasites in animals that feed upon it. 
Too much care cannot therefore be taken in the selection of 
the best kind of food, especially for young stock. It is even 
more important in those establishments where thorough¬ 
breds are reared that all drawbacks to the development of 
vigorous health should, as far as possible, be avoided. 
I may be told that there are many breeding establish¬ 
ments that correspond with what I have thought most 
desirable as far as locality and dryness of soil are concerned, 
and yet it is notorious that the foals and yearlings that are 
there reared are infested with worms. How is this to be 
accounted for? Let us suppose that an establishment of this 
kind is planned out, with suitable paddocks and buildings, and 
that horses, mares, and foals are placed upon it. Some of the 
animals, in all probability, have worms in their intestines. At 
the time they may be few in number, and of different varieties. 
It will not be long, however, before some of these parasites, or 
their ova, or both, will pass through the intestines and be de¬ 
posited on the pasture. Now it is to be remembered that the 
ova do not at once perish, nay, some of them may remain alive 
for a long time, and be taken up again by the same animal while 
feeding, or by a fresh occupant. The rapidity with which 
entozoa multiply is almost fabulous; and from the same soil 
being inhabited year after year with mares and their offspring, 
the surface may become covered with myriads of ova, and I 
can conceive that it would be almost impossible for a foal, on its 
first attempt to eat grass, to be very long before some of these 
ova were taken into its interior, and thus infest it with 
worms. There may be some truth in this theory, for the 
reason that the ova must be taken into the young animals from 
without; and where else should they get them but from the 
food they partake of? And as the foals and yearlings suffer 
more from parasites in the paddocks than they do on the 
