SCALY ECZEMA. 161 



irritation of the skin or mucous membrane, is well marked. In 

 obstinate cases, employ tartar emetio, or liquor arsenicalis as 

 directed on p. 151. 



Scaly Eczema {Pityriasis and Psoriasis). 



There is no essential difference between simple eczema and scaly 

 eczema, except that the latter is an advanced and more or less 

 chronic stage of the former. The adoption of this broad and 

 thoroughly sound view should do much to clear up the confusion 

 which exists concerning various forms assumed by non-contagious 

 skin inflammation. The old popular terms, " humid tetter " and 

 " dry tetter " may be taken to respectively designate the moist and 

 scaly forms of eczema. As the word, psoriasis, means mange; it 

 is inapplicable to a non-contagious disease. Pityriasis, signifying 

 a bran-like condition, is a suitable eixpression for a scaly inflamma- 

 tion of the skin. " Queensland Itch," often met with among horses 

 in Eastern Australia, comes under this heading. In India, eczema 

 which takes the same form, is common during the hot weather 

 and " rains ; " and frequently invades the dock and space between 

 the thighs. 



The scaly_ stage of eczema is often accompanied by cracks in the 

 affected skin on account of the existing inflammation having inter- 

 fered with the action of the oil glands, the function of which is to 

 keep the skin soft and pliable. The inflammation, also, causes 

 thickening of the part. In bad cases, the cracks exude serum and 

 blood, which aid in the formation of scabs. When it appears 

 behind the knees, it is termed '' mallenders ;" when in front of the 

 hocks, " sallenders." It a,lso occurs on the neck, just in front of 

 the withers ; on the upper surface of the root of the tail ; and, 

 more rarely, in other positions, in which cases the eruption receives 

 no distinctive name. Mallenders and sallenders are not very 

 amenable to treatment, and rarely occur except among horses 

 whose stable management has been much neglected. 



TREATMENT in ordinary cases is the same as that of simple 

 eczema (p. 151). When the skin becomes fissured or very rough, 

 it is well to soak the affected part in oil to remove the scales, and 

 after that to use dilute nitrate of mercury ointment. Or, after 

 washing the part, rub in the following ointment: — Chrysophanic 

 acid, 20 grains ; Wright's liquor carbonis deterg., 20 minims ] 

 white precipitate (hydr. amm. chlor.), 20 grains ; benzoated lard, 

 2 oz. The paxt should neither be fomented nor poulticed. The 

 horse may have linseed mashes or oil, given to him daily, as well 

 as carrots or green fodder. Beans and kiln-dried or musty oats 



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