DISEASES OF THE SKIN. 325 



The disease consists in paralysis of the nerve ends that control the 

 volume of the capillary vessels in certain areas of skin, thus permit- 

 ting the vessels to expand, their contents in part to exude, and thus 

 produce a soft, circumscribed swelling. 



Treatment. — Administer a full dose of Epsom salt. Give soft, 

 easily digested feed, and wash the affected parts with a solution of 

 bicarbonate of soda (common baking soda), 8 ounces to the gallon of 

 water twice a day, or diluted glycerin may be applied to the skin. 

 If it assumes a persistent tendency, give a tablespoonful of the 

 follov>ring powder in the feed three times a day: Cream of tartar, 

 sulphur, and nitrate of potassium, equal parts by weight; mix. 



Eczema is a noncontagious inflammation of the skin, characterized 

 by any or all of the results of inflammation at once or in succession, 

 such as erythema, vesicles, or pustules, accompanied with more or 

 less infiltration and itching, terminating in a watery discharge, with 

 the formation of crusts or in scaling off. The disease may run an 

 acute course and then disappear, or it may become chronic ; therefore 

 two varieties are recognized, vesicular (or pustular) and chronic 

 eczema. 



Causes. — Eczema is not so common among cattle as in horses and 

 in dogs, in which it is the most common of all skin diseases. Among 

 cattle it is occasionally observed under systems of bad hj^giene, filthi- 

 ness, lousiness, overcrowding, overfeeding, excessively damp or too 

 warm stables. It is found to develop now and then in cattle that are 

 fed upon sour substances, distillery swill, house or garden garbage, 

 etc. Localized eczema may be caused by irritant substances applied 

 to the skin — turpentine, ammonia, the essential oils, mustard, Span- 

 ish-fly ointment, etc. Occasionally an eruption with A^esiculation of 

 the skin has been induced by the excessive use of mercurial prepara- 

 tions for the destruction of lice. It is evident that eczema may arise 

 from local irritation to the skin or from an autointoxication. Cattle 

 fed on the refuse from potato-starch factories develop a most obsti- 

 nate and widespread eczema, beginning on the legs. 



Symptoms. — In accordance with the variety of symptoms during 

 the progress of the disease we may divide it into different stages or 

 periods: (1) Swelling and increased heat of the skin; the formation 

 of vesicles, which are circumscribed, rounded elevations of the epider- 

 mis, varying in size from a pinhead to a split pea, containing a clear, 

 watery fluid; (2) exudation of a watery, glutinous fluid, formation 

 of crusts, and sometimes suppuration, or the formation of vesicles 

 containing pus (pustules); (3) scaling off (desquamation), with 

 redness, and thickening of the skin. From the very beginning of 



