226 



LAMENESS OF THE HORSE 



are on record in veterinary literature. This ailment affects old 

 horses more frequently than it does young and is seen in all 

 breeds of animals including mules. 



Symptomatology. — This disease develops slowly, and pro- 

 gressively increases in severity as a rule, Init does not ordinarily 



Fig. 52— Spring-halt. 



constitute cause for rendering an animal unserviceable. While 

 the affection is sometimes l)ilateral (occasionally affections of 

 the forelegs are reported) and the extreme flexion of the legs 

 in the spasmodic manner which characterizes spring-halt, cause 

 great waste of energy during locomotion, yet such cases are 

 rare. Usually the ailment is markedly evinced when subjects 

 are first taken from the stable, but as they are exercised the 

 manifestation diminishes, and in many instances it completely 

 subsides. The condition is generally more noticeable when the 

 subject is made to step backward. In some animals there is 



