COMPARATIVE UNSOUNDNESSES. 705 



cause, and not as a result of unsoundness. " Contracted heels '* are 

 chiefly brought on by the horse going on his toe ; by allowing the heels 

 to grow too long ; by improper shoeing; and by the practice of cutting 

 away the bars and frog. We often find thrush associated with con- 

 tracted heels. A veterinary surgeon would be extremely chary of 

 giving a certificate of soundness to an animal with " odd " or con- 

 tracted feet. See page 168. 



Cornea^ species on the. — The cornea (p. 339) is not very unfre- 

 quently wounded by accident. The scar is at first of a bluish colour, 

 but subsequently turns white ; a fact which may afford some clue to 

 the length of time that has elapsed since the wound was inflicted. On 

 page 346 we see that the cornea is punctured in the operation for 

 " worm in the eye." " The opacities are, only when sufficiently large, 

 or when so situated as to interfere with sight, to be regarded as 

 causes of unsoundness" {Williams^. 



Cracked heels {]). 154). — As regards the question of soundness, it 

 matters little if we are unable to draw a sharp line of distinction 

 between this disease, and " grease " ; for any case of the former which 

 might be classed as one of the latter would be an undoubted unsound- 

 ness. Although a slight roughness, or a few scabs at the back of the 

 pastern or pasterns, as the case may be, might be passed over; still, 

 if the general surface of the skin of the part be inflamed, even without 

 being broken, the horse should be regarded as unsound ; for such a 

 condition is often difficult to remove, and may give rise to a great deal 

 of inconvenience to the affected animal. In old standing cases, the 

 fissures in the skin may apparently heal up all right; but as long as 

 any thickening of the part, or inflammation in it, remains, the skin 

 will be apt to become sore again on very slight provocation. If the 

 skin be at all tender, or if there exist in it any scars from previous 

 attacks of this inflammation, the ailment will be liable to assume an 

 aggravated form, or to commence anew, as the case may be, if the 

 animal be put to fast work, on account of the skin of the part being 

 subjected to a greater amount of bending, and being more exposed to 

 chill, than when the work was slow. The fibrous tissue which forms 

 the white mark left by a scar, does not possess the same degree of 

 elasticity and suppleness as the uninjured skin. Besides, when the 

 skin is inflamed, it is but poorly supplied with lubricating fluid from 

 the oil glands, and is then ill-calculated to resist the effects of severe 

 and continued bending. 



Crib-biting (p. 555). 



Ciitting (p. 90). 



Eczema. — See "Skin Diseases" (p. 707). 



Feet, brittle.— ^ee "Sole,. weak" (p. 707). 



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