GEEASE. 



1018 



consists in inflammation of the sweat glands, foMfewed by an of- 

 fensive, white, oily discharge from the heels. The acrid character 

 of the discharge often causes large portions of the skin to slough 

 away, leaving ugly sores behind. 



Symptoms. — There is genei'ally more or less swelling of the 

 legs, which, if not speedily relieved, is followed by a discharge; 

 the hair falls oft', and the skin is reddened and inflamed. The 

 parts are very painful and hot, and in many cases the least press- 

 ure of the hand will make the horse twitch up his leg, and con- 

 tinue to hold it up for some time. 

 In other cases, when made to move 

 about in his stall, or when taken 

 out of his stable in the morning, 

 he will keep twitching up his legs 

 as if he were aflfected with string- 

 halt. Exercise appears to relieve 

 the pain, as after being walked 

 for ten or fifteen minutes, he goes 

 quite free. As the disease ad- 

 vances, the skin cracks, and the 

 discharge increases, becoming more 

 and more purulent and offensive. 

 (A good illustration of its appear- 

 ance at this stage is given in Fig. 

 871.) The swelling increases, not 

 being confined to the heels, but in- ^i^^- 8~i.— A bad condition of grease, 

 volving the front of the fetlock joint, and in some cases extending 

 uj)wards to the hock. The cracked condition of the legs and heels 

 undergoes a change of structure, and fungoid granulations spring 

 up similar in form to a bunch of keys; this is called the "orapy 

 stage," which may* vary considerably in structure, at one time be- 

 ing very vascular, bleeding readily when touched, in other in- 

 stances it loses its vascularity, and becomes hard and horny ; from 

 between the crevices of the grapes an' ichorous, glairy discharge 

 continues. 



There is a small parasite, called sarcoptes hippopodus, which is 

 sometimes found in chronic grease, an illustration of which I here 

 give largely magnified, from Williams, who says this class of insect 

 may be also common to mange. The disease induced by it is called 



