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Home Department. 
ON THE HEREDITARY DISEASES OF HORSES. 
By Finlay Dun, Jun., V.S., Lecturer on Materia Medica, &c., at 
the Edinburgh Veterinary College. 
Prize Essay. 
( From the Journal of the Royal Agricultural Society , vol. XIV.) 
FIRST PART. 
Our everyday experience of the production and develop- 
ment of plants and animals at once suggests the existence of 
the great natural law embodied in the familiar saying, “ like 
produces like.” In accordance with this law the peculiar 
properties, characters, and qualities of the parent — whether 
good or bad, healthy or diseased, external or internal — are 
transmitted to the offspring, or, in a word, are hereditary. 
To illustrate this natural law of hereditary transmission, with 
especial reference to the diseases of horses and cattle, is the 
object of this report, and, in treating of the subject, we shall 
notice — 
i. General hereditary characters, both healthy and dis- 
eased. 
ii. The hereditary diseases of horses. 
hi. The hereditary diseases of cattle. 
i. Many interesting and valuable facts have been recorded 
which prove, beyond all doubt, the hereditary tendency of 
many of the physical, mental, and moral qualities of man. 
Parents transmit to their children their own — or, at all events, 
similar — external forms, similar intellectual capacities, tempe- 
raments, dispositions, virtues, and vices, as well as similar 
tendencies to particular diseases. Certain families are re- 
markable, during many centuries, for tall and handsome 
figures, and for a striking similarity of features ; whilst others 
perpetuate a less perfect form, the peculiar deformities of 
the parents reappearing in the children of each successive 
generation. For example, the thick upper lip of the members 
of the imperial house of Austria has been a characteristic of 
the family for centuries ; and every one is familiar with the 
curious case of the Yorkshire family with their six fingers 
and toes, which remarkable conformation has continued for 
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