240 LAMENESS. 



have a fair chance. It has been already stated that it is 

 necessary to make the horse run both from and to the 

 observer, and it may be necessary to do this repeatedly ; but if 

 an examiner cannot determine the existence in two or three 

 minutes, it is better to put the horse up again, as the exercise 

 has a tendency to decrease, or even to remove the lameness. In 

 some very slight cases, it may be necessary to place a rider on 

 the horse, as the weight upon the back will cause the mani- 

 festation of the lameness. As a rule, however, it is better not 

 to do this, especially if the animal be a spirited one. 



There are some lamenesses which are only manifested after 

 sharp work, and in such cases it is necessary to give the horse 

 half-an-hour's trot or gallop, tying him afterwards in a stall 

 until he becomes cool. When taken out of the stable and 

 trotted after such a test, lameness, if in existence, will most 

 assui-edly be detectable. Some veterinary surgeons do this 

 with every horse they examine ; but it is quite needless in 

 ordinary cases, and it is only when some suspicion exists that 

 such a test is necessary, such as badly-formed hocks, splints 

 near the knee, or some alteration of structure in any part of 

 the limb, or in cases w^here there is " pointing " while at rest, 

 or where the disease is very slight. 



The gait only is sometimes sufficient to determine the seat 

 of lameness, and in some cases it is the only guide ; but it is 

 a good rule, and one that should never be neglected, to examine 

 the lame limb while the animal is in a state of rest. 



By the latter method we discover lameness by positive and 

 negative signs. For example, if there be heat, pain, or swelling 

 in any part of the limb, discoverable by manipulation, the 

 evidence is 'positive that the cause is in such a part; but if, 

 on the other hand, there be neither pain, heat, nor swelling 

 in the Hmb, nothing in the superficial parts of the foot to 

 account for it, we must conclude that it is deep-seated in the 

 foot, or in a part thickly clothed by healthy tissues, and we 

 must arrive at a conclusion by negative evidence, assisted by 

 peculiarities of gait. 



Lameness may be caused by a strain of a ligament, muscular 

 tissue, tendon, by fractures, diseased bones, cartilage, or fibro- 

 cartilage, morbid conditions of the skin ; neuromatous and other 

 tumours; plugging of arteries; accidents, as "pricks" in shoe* 



