MANGE. 273 



a miasm productive of a virulent mange, very difficult to be re- 

 moved. Close confinement, with alted food, is even more certainly 

 productive of mange : thus dogs who have come from distant 

 countries, on ship-board, are generally afi'ected with it. Very high 

 living, with little exercise, is a frequent cause : a state nearly ap- 

 proaching to starvation is also not unfavourable to it. In both 

 these apparent contrarieties the balance between the skin and the 

 digestive functions is not preserved, and the disease follows as a 

 necessary consequence. The disease has some permanent and 

 fixed varieties , it has also some anomalies ; but the pruritus or 

 itching is common to all. 



The scabby mange, one of the most common fonns under which 

 this eruptive complaint appears, is an extension of the secretory 

 pores of the skin in very minute red vesicles, that at first are dis- 

 tinct, but as they extend become pustular, confluent, and scabby. 

 Sometimes simple linear cracks of the cuticle seem to pour out a 

 serous fluid, which concretes into a scab. It is occasionally con- 

 fined to the back ; at others it is found principally in the joints of 

 the extremities. 



The red mange, so called from a redness of both skin and hair 

 in the parts afi'ected, is likewise not unfrequent, and partakes much 

 of an herpetic character. In this variety there is less pustular 

 eruption, but nearly the whole skin of the body, particularly in 

 white-haired dogs, is in a state of active inflammation : it is also 

 hot to the feel, and itches intolerably. In the red mange the hair 

 itself becomes morbidly aff^ected, and alters in its colour, particu- 

 larly about the extremities : it also falls off", and leaves the skin 

 bare, much thickened, and puckered into stubborn wrinkles. Dogs 

 with the strong coarse hair called wired are very liable to this 

 state ; in which a magnifying glass applied will often detect innu- 

 merable minute ulcerations covered by furfuraceous scales. 



A direct ulceration of the sebaceous glands is another form of 

 mange, but is much less frequent than either of the former : these 

 glands in this state appear to become internally ulcerated, and 

 have their sebaceous outlet preternaturally enlarged- The afi«c- 



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