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Hereditary Diseases of Horses. 



the joints and muscles to the heart and its investing membrane, 

 and it is the danger of this change in the seat of the disease that 

 renders rheumatism so formidable, and often so fatal. It always 

 leaves the parts affected so altered as to be extremely predis- 

 posed to subsequent attacks ; and it is more than probable that 

 this altered condition is reproduced in the progeny of rheumatic 

 subjects, and constitutes in them the inherent tendency to the 

 disease. 



Horses sometimes suffer from rheumatic inflammation in the 

 fibrous sheathing envelopes of the muscles of the neck, consti- 

 tuting what is popularly known as the chords. When thus affected 

 the animal is very stiff, remains as much as possible in one po- 

 sition, and is unwilling to bend his neck either to one side or 

 another, or to elevate or depress his head. There is always more 

 or less fever, with a strong full pulse. Sometimes, as in lumbago 

 in the human subject, it affects the muscles of the back and 

 loins, causing stiffness, tenderness, and pain, which are espe- 

 cially evinced on moving or turning the animal. These rheu- 

 matic affections are very readily produced in predisposed sub- 

 jects by exposure to rain and cold, especially when accompanied 

 by over-heating or exhaustion. Rheumatism sometimes occurs 

 in horses as a prominent symptom of that epizootic affection 

 which usually receives the much-abused title of influenza. In 

 such cases the rheumatism is of a somewhat more sub-acute or 

 chronic character than common, and is accompanied by that low 

 debilitating fever so often the concomitant of epizootic maladies. 

 It usually affects all parts of the body susceptible of the rheu- 

 matic inflammation, is attended particularly by those symp- 

 toms which indicate disease of the heart and pericardium, as an 

 irregular intermittent pulse, and often terminates fatally by 

 effusions into the pleurae or pericardium, thus causing death by 

 arresting the motions of the heart. As we shall have again to 

 notice rheumatic diseases when speaking of cattle, we leave the 

 subject for the present, and proceed to the scrofulous or strumous 

 inflammation. 



The scrofulous diathesis, or constitution, is not uncommon 

 amongst horses. It assumes many degrees of intensity, and pre- 

 disposes to many diseases. It is most apt to discover itself in 

 horses with narrow chests, large flat sides, weak loins, soft flabby 

 muscular systems, soft thin skins, fine silky hair, large badly- 

 proportioned limbs, and large weak joints, and in those in which 

 digestion is often impaired, excretion irregular, and circulation 

 weak and easily accelerated. In an animal affected by scrofula 

 the blood is in an abnormal condition. There is an alteration in 

 the relative quantity and quality of its various constituents, con- 

 sisting chiefly in a diminution of the red corpuscules, and an 



