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Hereditary Diseases of Horses, 



There is, at tlie same time, a good deal of constitutional fever, 

 with a full and bounding pulse. The swelling of the leg is in 

 the first instance inflammatory, being hot and tender, and the 

 skin over the part afFected, hard and tense. Such swellings 

 may by judicious treatment be removed ; but, in cases of a 

 chronic character, or where the same limb has been previously 

 afFected, lymph is effused, forming hard and nodulous and even 

 diffuse swellings, which often cause lameness by interfering 

 with the motions of the joints or tendons. These indurated 

 swellings must be carefully distinguished from the serous effu- 

 sions above noticed, which, although giving the animal an un- 

 sightly appearance, do not materially impair his usefulness. 



Grease consists in a morbid condition of the sebaceous glands 

 of the horse's heels and fetlocks. It occurs in various degrees 

 of intensity ; sometimes as a mere scurfy itchiness of the skin 

 about the fetlocks, more commonly of the hind extremities ; 

 sometimes attended with much inflammation, causing great heat, 

 pain, and swelling, and an ichorous foetid discharge ; sometimes 

 causing falling off of the hair about the heels, and the formation of 

 deep cracks and fissures ; and sometimes becoming so violent and 

 inveterate, as to cause eversion of the sebaceous glands, forma- 

 tion of granulations, and secretion of pus, constituting the loath- 

 some complaint termed the grapes. There are few diseases 

 better deserving the epithet of hereditary than grease, and few 

 in which the hereditary nature can be more easily discovered 

 and traced. Almost every practitioner can bring to his recollec- 

 tion cases showing the tendency of this disease to descend from 

 parent to offspring. A friend of mine some years ago pur- 

 chased a valuable four year-old-entire horse, adapted for agricul- 

 tural purposes. When bought, he appeared perfectly sound, 

 and his limbs were nearly black, well formed, and fine ; within 

 a short time, however, they became thick and greasy. And, 

 although the mares to which he was put were perfectly free 

 from such faults, the progeny have shown, in every case where 

 they can be traced, unmistakeable evidence of their inheriting 

 the greasy diathesis of their sire. They have all been found 

 liable to swelled legs when they stand idle for a few days, 

 most of them have been the subjects of repeated attacks of weed, 

 all are afFected, particularly in spring, with scurfiness of the 

 skin of the hind extremities and excessive itchiness, and lose at 

 a very early age their flatness and smoothness of limb. The 

 faults occur to a greater or less degree in all the stock of this 

 horse by many difFerent mares, and are distinctly traceable to 

 the third generation. But, although grease is undoubtedly 

 hereditary, and is therefore readily induced by comparatively 

 simple causes, still it is frequently caused, and is always aggra- 



