FRACTURES. 23 



explains why lesions of the horns are often follo\Yed by such profuse 

 bleeding. 



(3.)- The horn secreted by the papillcB of the horn band (which is 

 analogous to that of the coronary band of the horse) forms a cone 

 varying in its curve in various breeds. Its base is hollow, and 

 contains little depressions holding the papilla from which the horn is 

 secreted. From its base up to the end of the horn core the walls pro- 

 gressively increase in thickness. From this point it is solid ; in a 

 fully-grown horn the bone does not extend more than one-half or 

 two-thirds of the entire length. 



In the adult, the development of the horns varies with different 

 breeds and is affected by sex. In the bull the horns are short, but in 

 the cow and ox long. Short and fine in animals of improved breed like 

 the Durham, they are long and thick in breeds of working oxen. 



Injuries affecting the horns are of three classes, determined by the 

 part affected. 



1. Detachment of the horn or sheath. 



2. Laceration : — 



(a) Of the horny sheath alone. 



(/>) Of the horny sheath and of the horn core. 



(c) Of the horn core alone, the horny sheath remaining intact. 



3. Fractures : — 



(a) Of the terminal half of the horn. 

 (h) Of the lower half. 

 {c) Of the base. 



DETACHMENT OF THE HORNS. 



When the 3'oke is badly fitted or padded, it is liable to cause a 

 continual strain or a succession of shocks producing chronic inflam- 

 mation of the keratogenous membrane. Should the end of the horn 

 then be struck heavily, it is quite possible that the horn will either 

 partially or wholly be detached. In this case it falls away without there 

 necessarily being any important lesion of the horn core. 



Such accidents are not infrequently caused by the driver striking the 

 ox on the horn with the yoke in order to keep it quiet while it is being 

 harnessed. 



The prognosis of this condition is not grave, except for the fact 

 that working animals cannot be used until the horn is completely 

 regrown. 



The treatment simply consists in thoroughly cleansing and disin- 

 fecting the horn core and then applying a protective dressing. The 

 bony basis is surrounded with a mass of tow saturated with an antiseptic 



