SAND CRACK. 35 



working oxen drawing heavy loads, though in very exceptional cases it 

 affects animals which have never worked. (Moussu describes one case 

 in a young ox where four sand cracks existed simultaneously.) It may 

 also result from injuries to the coronet. In contrast to the case of the 

 horse, and owing to the different conditions under which the ox performs 

 its work, the disease is commoner in front than in hind feet. In 

 drawing, the ox's front limbs play the principal part, and the animal 

 pivots, so to speak, on the claws of the front limbs. 



The position of the crack may vary. It is commonest on the inner 

 surface of the claw, rare at the toe, and still rarer at the quarter. 

 It is often superficial and complete, extending throughout the entire 

 height of the claw, but not throughout its thickness ; sometimes it is 

 complete and profound, the fissure then extending to the podophyllous 

 tissue. 



The symptoms are purely local in the case of superficial lesions. 

 When the injury is deep seated, or when it originates in a wound of the 

 coronet, lameness is present. Intense lameness, swelling of the coronet, 

 and blood-stained or purulent discharge point to grave injury and 

 probable complications. 



Diagnosis is easy. The prognosis naturally varies with the symptoms. 

 It is favourable when the fissure is merely superficial, but becomes grave 

 when it is deep seated and the animal is exclusively used for heavy 

 draught. 



Treatment. When the lesion is superficial and unaccompanied by 

 lameness, no surgical interference is necessar3\ Rest or very light work 

 is alone required. As soon as lameness appears, rest is obligatory. The 

 application of antiseptic poultices, containing 2^ to 3 per cent, of carbolic 

 acid, creolin, etc., usually alleviates pain in a short time, and facilitates 

 healing in the depth of the fissure. 



In exceptional cases, where complications have occurred in conse- 

 quence of suppuration beneath the fissure, suppuration in the coronary 

 region, or necrosis of the podophyllous tissues, an operation becomes 

 necessary, and is of exactly similar character to that performed under 

 like circumstances in the horse. 



Over a space of 1 to IJ inches on either side of the fissure the horn 

 is thinned "to the blood," and the subjacent dead tissue removed. The 

 claw is then thoroughly cleansed with some antiseptic solution, the 

 wound freely dusted with equal parts of iodoform, tannin and boric 

 acid, and covered with pads of tow or cotton wool, fixed in position by 

 appropriate bandages. After such operations a long rest is essential 

 for complete recovery, during which, however, the animal may be 

 fattened. 



The object of operation is to prevent complications, like chronic 



D 2 



