912 



Herpes. 



circular margin of wliicli bears vesicles the size of a pin's head 

 (herpes tonsurans vesiculosus) ; in the center the skin appears 

 normal except for slight scaling. The vesicles soon dry and 

 form brown crusts, while round about fresh vesicles form. In 

 other spots one may see only small, somewhat raised, slightly 

 scaling circles which are reddened at their periphery (herpes 

 tonsurans maculosus). The bristles rarely fall out and no large 

 crusts form; itching also is absent. Transmission by mutual 

 contact easily occurs, although artificial transmission to pigs 

 has so far not been successful ( Siedamgrotzky, Schindelka). 



In this category must probably be classed the skin disease described by 

 Schindelka under the name of pityriasis rosea. It affects pigs 5 to 8 weeks old 

 and is accompanied by slight general symptoms (debility, diminished appetite, 

 retarded defecation, moderate tympanites), resulting in recovery in 2 to 3 weeks. 

 On the lower chest and belly and also on the lower surface of the neck, lentil sized, 

 slightly prominent bluish red spots arise which appear to be composed of minute 

 nodules. The spots spread peripherally and become pale in the middle where the 

 skin heals with fine scaling. This otherwise l^enign affection simulates the like- 

 named skin disease of children (Gibert) which is generally looked upon as of a 

 parasitic nature. Schindelka tried without success to transmit it to pigs and dogs; 

 no fungi could be found in the foci of the lesions. 



(e) Herpes in the Dog. 



The disease generally begins on the head, on the limbs, 

 and on the neck, and not infrequently passes on to the remain- 

 ing parts of the body, or at times it begins in these parts. 



The exanthema 

 occurs generally as 

 herpes tonsurans 

 crustaceus and is 

 more or less simi- 

 lar to that describ- 

 ed in cattle. In 

 the course of a 

 few weeks a sharp- 

 ly circumscribed 

 scaly layer of var- 

 iable thickness de- 

 velops, which at 

 first is loose, but 

 afterwards forms a 



Fig. 133. Hlmjaorm irith smh formation in a dog. firm SCUrfv Or aS- 



bestos-like crust 

 which cements the hair and gradually grows to a size a little 

 larger than a dollar piece. The hairs become loosened and finally 

 lifted from the hair follicle, remaining fixed in the crusts, and 

 the root ends may be seen on the under surface of the crusts 

 when these are removed. In the further course, according to the 

 species and age of the animals, the skin is either quite bald or 

 studded with many little hair stumps, of copper to brownish red 

 color, dry or moist, thickened or of normal thickness, and bear- 



