HEREDITARY DISEASES OE HORSES. 
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subjected in training, consisting of inflammation of the 
periosteum investing the cannon bones, especially of the 
hind limbs, and, when neglected, often running on to caries 
and necrosis. 
From their weak and unsound constitution, horses of a 
scrofulous diathesis are unusally prone to glanders and farcy 
—two forms of a disease peculiar (at least as an original 
disease) to the equine species. As has been already re- 
marked, it is characterised by a specific unhealthy in- 
flammation, identical in all important characters with the 
syphilitic inflammation in man. From the dire and loath- 
some nature of glanders, and the terror in which it is held, 
animals affected by it are never used for breeding, so that we 
have little opportunity of judging of its hereditary nature. 
There is no evidence (so far as I know) which proves it to be 
directly hereditary,* but there is no doubt that the progeny 
of a glanderous horse would exhibit an unusually strong ten- 
dency to the disease. Its ordinary predisposing causes are, 
many of them, hereditary : it is very prone to attack animals 
of a weak or vitiated constitution. It is emphatically the 
disease which cuts off all horses that have had their vital 
energies reduced below the healthy standard, either by 
inherent or acquired causes. Glanders is also sometimes 
caused by inoculation ; is frequently produced in healthy 
subjects by mismanagement, as by insufficient food, want 
of shelter, and overwork ; and often supervenes on bad 
attacks of influenza, strangles, diabetes, and other diseases 
which debilitate the system, or impair the integrity of any of 
its more important parts. These causes appear to possess 
the power of engendering in the constitution of the horse 
a peculiar poison, which, as it reproduces itself, and spreads 
to all parts of the body, gives rise to the characteristic 
symptoms of glanders, causing, sooner or later, a breaking 
up of the system, and a fatal prostration of the vital powers. 
This poison produces in the blood abnormal changes, which 
vitiate that fluid, and unfit it for healthy nutrition. t From 
the irritant action of the morbid fluids passing through 
them, the lymphatic glands and vessels become inflamed, 
and lymph is deposited. This, however, being of an un- 
healthy nature, soon runs on to softening, which extends to 
* Though I am not aware of any facts proving glanders to be congenital, yet 
I think there is every probability that such is the case ; for it is notorious that 
syphilis, the analogous disease in the human subject, is congenital, and often 
appears at birth in the children of women affected by that disease. 
f A comparison of the two subjoined analyses will show the great difference 
in composition between the blood of healthy arid of glanderous horses — a differ- 
