500 Veterinary Medicine. 



These are mostly situated at the roots of the mane or tail or on 

 the sides of the neck, withers or trunk, and as a rule produce a 

 pruritus, resembling that of scabies in its intensit}'. When the 

 exudate agglutinates a tuft of hair, enclosing it in a dense 

 crust, the hairs ma}' be lifted from their follicles and thus small, 

 round spots of depilation appear. If recovery ensues and new hair 

 starts, it differs in color from the old and gives a dappled appear- 

 ance to the skin. In many cases, however, the points of erup- 

 tion and encrustation become confluent and an extensive area of 

 bareness, with more or less abrasion, and even ulceration may be 

 formed. 



Megnin mentions two cases and the author can adduce an- 

 other in which the eruption appeared in vertical lines, so that the 

 skin of the trunk was raised in a series of elevated lines or ridges, 

 running transversely to the body, like the stripes of a zebra. In 

 the author's case the skin seemed to be thrown into a series 

 of folds to the production of which the cutaneous muscle evident- 

 ly took part. The itching was doubtless the immediate cause. 



Diagnosis is based largely on the suddenness of the eruption ; 

 on its limitation to a given area instead of spreading from the 

 primary seat of invasion as in acariasis ; on the fact that it is usu- 

 ally confined to a single animal and has not spread with the use 

 of the same brush, comb and rubber ; and on the absence of acari 

 and vegetable parasites from the affected parts. The absence of 

 chicken roosts or manure is anotlier valuable indication. 



Prognosis. Appearing in spring or early summer, the disease 

 is liable to persist until the advent of cold weather in fall, and 

 even after a winter's intermission there is a strong tendency to its 

 re-appearance on the following spring or summer. The intoler- 

 able itching interferes seriousl}' with docility and steadiness in 

 harness, and the loss of hair renders the subject very unsightly, 

 and as a family or driving horse practically useless. 



Treatment. As in cases of eczema the general and special 

 causes should be corrected by hygienic and general medicinal 

 measures, laxatives, diuretics, antacids, tonics, and in the ad- 

 vanced stages, alteratives coming in as important factors. (See 

 under acute eczema). Great care should be taken to prevent ir- 

 ritation by pressure of the harness, and shade and daily cold 

 spraying may be availed of. 



