Symptoms. 



971 



In dogs in which, acariasis is of the greatest practical im- 

 portance on acconnt of its frequency and severe course, the ill- 

 ness appears in two principal forms. 



The squamous form declares itself as a squamous eczema 

 which remains limited for a time to small surfaces. On the 

 orbits and in their neighborhood, further on the elbows or on 

 single toes, more 

 rarely on the 

 body, the hair 

 falls out in small 

 patches, and in 

 this way round- 

 ed, often sharp- 

 ly defined pro- 

 nounced bald 

 spots (Fig. 154) 

 arise, reminding 

 one of alopecia 

 areata. At these 

 places the unpig- 

 mented skin is 

 somewhat red- 

 dened and most- 

 ly covered with 

 bran-like scales. 

 Sometimes it is 

 only bald and 

 may contain 

 small nodules. 

 After a certain 

 time the skin as- 

 sumes a bluish 

 gray color on the 

 affected spots. 

 In many cases 

 the affection be- 

 gins with round, 

 red or copper- 

 colored spots 

 and scarcely 

 perceptible scal- 

 ing. But after a 

 time these spots 



assume a lead gray color (Schindelka 

 most slight. 



In this form the affection may last for months, and it may 

 even remain unchanged to the end ; it causes scarcely any itch- 

 ing and exerts no influence on the general condition of the af- 

 fected animal. But often the pathological changes in the skin 

 attain a high degree, or the affection occurs from the beginning 

 in the followingdescribed form. 



Fi"-. 154. 



Acarus mange in the dog. Falling out of the 

 hair in sharply circmuseribed patches. 



i). Itching is absent or at 



