DISEASES OF THE SKIN. 337 



nervous affections may cause it. The disease consists in a paralysis 

 of the nerve ends that control the volume of the capillary vessels in 

 certain areas of skin, thus permitting 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 food, 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 glvcerin may be applied to the skin. If 

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

 powder in the feed three times a day : Cream of tartar, sulphur, and 

 nitrate of potash, e(jual parts by weight: mix. 



Eczema is a noncontagious inflammation of the skin, characterized 

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

 such as erythema, vesicles, or pustules, accompanied by 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, vesieul<i;\ or pustular^ and chronic eczema. 



Causes. — Eczema is not so conunon 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 hygiene, 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 vesiculation 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 auto-intoxication. Cattle 

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

 nate and widespread eczema, beginning on tlie legs. 



Symptoms. — In accordance with the variety of symptoms during 

 Ihe 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 pin head 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 con- 

 taining pus (pustules) ; (3) scaling off (desquamation), with redness, 

 and thickening of the skin. From the very beginning of the disease 



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