DISEASES OF THE SKIN. — EXTERNAL PARASITES. I99 



FOLLICULAR MANGE. 



This species of mange, from the acari being buried in the 

 sebaceous and hair follicles, and their migration to a great 

 extent thus hindered, is not so contagious as the sarcoptic 

 form. " Indeed, an affected dog may cohabit with others for 

 some time without extending the disease.* The animal 

 whose case is described by Weiss, lived for from eight to fifteen 

 days with other dogs, which remained unaffected. This fea- 

 ture in follicular scabies is accounted for by the situation and 

 habits of the parasite, and its conformation. Burrowing 

 deeply into the follicle, it only leaves its habitation, in all 

 probability, when carried from it by the fluid thrown out in 

 the follicle, for its limbs are very short, and are not furnished 

 with suckers so that it is not well adapted for travelling, dif- 

 fering in this respect from the ordinary acarus. Nevertheless, 

 in some instances the slightest accidental contact will suffice 

 for its transference from a diseased to a healthy dog ; and 

 when conveyed experimentally to the skin of the latter, it 

 propagates it in a very remarkable manner. Haubner de- 

 posited several, with a view to elucidate the contagiousness 

 of the affection, and he found that, in about twenty-four 

 hours, there was a slight tumefaction of the skin where they 

 had been placed ; in forty-eight hours the follicles contained 

 a purulent fluid, in which young and adult acari and ova could 

 be perceived. The eruption extended ; but eventually the 

 parasites disappeared, and a spontaneous cure took place."t 



Symptoms. — These likewise are not so easy of distinction 

 as in sarcoptic mange. At first, circumscribed tumefactions 

 of the skin take place : these tumefactions are hot, and usually 

 blotchy, or patched with red. In a very short time small 



* This fact will serve to explain why the contagiousness of scabies has 

 been denied and affirmed by different authorities in this country, where 

 only one kind of parasitic " mange " has been hitherto recognized in the 

 dog. 



t Fleming's " Veterinary Sanitary Science," vol. ii. p. 457. 



