64 2 
HEREDITARY DISEASES OF HORSES. 
briefly of tabes mesenterica and of consumption in horses, 
because we shall have to return to them when speaking of 
the hereditary diseases of cattle, in which they are more 
common than in the horse. 
These are the most common forms in which a scrofulous 
diathesis shows itself, but there are other irregular forms 
which it also sometimes assumes. In early life especially, 
we recognise it in intractable swellings of the joints, from 
unhealthy inflammation of their synovial fringes, and in 
accumulations of pus in various parts of the body. These 
two forms are often met with in different individuals of the 
same stock, and are always notoriously hereditary. I know 
at present of two entire horses, both of fine symmetry and 
apparently sound and vigorous health and constitution, that 
have for several seasons got stock, many of which have died 
within a short time after birth from these complaints, and 
others have long continued sick and ailing. A pony, in 
sound health, and which had previously reared a strong and 
vigorous foal, got by another sire, had a foal to one of these 
horses. From birth it was weak on its legs, and died before 
it was three weeks old : an immense accumulation of pus 
was found underneath the psoas muscles, and all the larger 
joints were inflamed, especially the stifle joints. In the 
succeeding year the same pony had another foal to the same 
horse, which again showed similar symptoms, and died about 
the same time after birth. Again, in the next year the pony 
was put to another horse, and had a foal which remained 
perfectly free from disease. This case, w T e think, distinctly 
proves the transmission by the sire of a scrofulous diathesis. 
The disease of the foals could not depend upon accidental 
circumstances, for a similar affection occurred in many 
of the stock got for several seasons by the same horse. The 
disease w 7 as in this instance ascribable to the sire, and not to 
the dam, — which is obvious from the fact, that the same 
mare produced and reared a healthy foal both before and 
after she had the tw r o diseased ones. This last observation 
must not, however, be misconstrued, as leading to the belief 
that diseases are inherited from the male alone ; on the 
contrary, form, disposition, and tendency to disease, all depend 
quite as often on the mother as on the sire. 
But a scrofulous diathesis, besides appearing in the forms 
above noticed, also constitutes a powerful predisposition to 
many diseases. In scrofulous subjects sore shins often 
occur — a complaint common in many racing studs, ap- 
pearing chiefly in young and rapidly-growing animals, 
depending on the excessive exertions to wdiich they are 
