AI.OPECIA CONGENITA. CONGENlTAIv BAI.DNESS. 



Cases of this kind have been met with in foals and calves, 

 which were born entirely bald or with only a few thin delicate 

 hairs scattered over the surface. In a calf observed by the 

 author, and which lived for several months, the body was almost 

 absolutely bald, and the mouth remained edentulous, a coinci- 

 dence which has been observed in other cases. The teeth belong 

 to the same class of embryonic tissues as the epidermis, and a 

 failure in the development- of the one is likely to entail a cor- 

 responding failure of the other. Schneidemiihl observed that 

 the few hairs present in such cases were especially delicate and 

 brittle. 



AI.OPECIA. POST PARTEM. AI.OPECIA AREATA. 



Normal shedding. Shedding out of time ; laminitis, dropsy, exudative 

 dermatitis, acariasis, ringworm, traumas, folliculitis. Debility, excessive 

 lactation, starvation, petechial fever, spoiled fodder. Without apparent 

 cause, alopecia areata, neurosis, micrococci, disease of derma. Symptoms : 

 general disorder has general shedding. Local disorder extends from a 

 centre. In horse with increased pigmentation. Treatment : correct general 

 causes, use hair stimulants, can tharides, kerosene, tar, pilocarpin, mercuric 

 chloride, cresol, iodine, balsam of Peru, silver nitrate. Arsenic. 



Acquired baldness is recorded in horse, cattle, sheep and dog. 



Causes. The simple shedding of hair occurs physiologically 

 in animals with the change of season, and if anything interferes 

 with the growth of the new hair a transient baldness may ensue. 

 If such shedding occurs from any cause at the wrong season, be- 

 fore the new hair has started, the baldness may be accentuated. 

 Thus shedding may occur in some forms of indigestion, in 

 laminitis, in dropsical swelling of the limbs or ventral aspect of 

 the body, in dermatitis with an exudation which concretes 

 around the hairs and raises them out of their follicles, in mange, 

 in demodectic acariasis, in circinate ringworm, in traumas as on 

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