DISEASES. ' 87 



to the dog, when it causes a most repulsive disease, and one very difficult to 

 eradicate. i -/' ; ' 



Some few years ago Mr. Wm. Hunting, F.R.C.V.S., in conjunction with Pro- 

 fesor Duguid, made a series of investigations and experiments in elucidation of 

 this disease, and the following description of symptoms and the diagnosis are 

 from an article hy the former gentleman, which appeared in the Veterinary 

 Journal, and afterward in pamphlet form: 



"The symptoms of the disease are seldom seen in the first stages; they consist 

 merely of circumscribed spots from which the hair falls, and upon which are 

 noticeable a few small pimples. These patches extend rapidly, and fresh ones 

 appear on other parts. Any portion of the skin may be affected, but the head, 

 legs, belly, and sides, are usually the seat of the disease. The affected places are 

 almost hairless, and what hair remains is easily pulled out; small pimples and 

 pustules stud the surface, the latter varying in size from a pin s head to that of a 

 pea. The confluence of the pustules, and the discharge of their contents, give 

 rise to scabs; these crack and bleed, and so produce a most repulsive appearance. 

 In white-haired dogs the skin is red; in all it is extremely hot, and emits an un- 

 pleasant odor. The irritation does not excite much scratching, but the dog fre- 

 quently shakes himself. More pain than itching seems to accompany the disease. 

 In cases where the whole body is affected loss of condition is most marked; and 

 in cold weather the almost total loss of hair may cause death, if the animal be 

 not kept in a warm place. This stage, too, is always accompanied by ravenous 

 appetite, due, probably, to the rapid loss of animal heat. 



"Diagnosis. In white dogs the color of the skin may cause the disease to 

 be mistaken for 'Red Mange' or 'Eczema.' The circumscribed spots in the first 

 stages may be confounded with some forms of Tinea, and the loss of hair and the 

 presence of scabs seen in the fully developed disease may easily be mistaken for 

 ordinary Fcabies. The pustules, the heat of the skin, and the comparatively slight 

 itchiness shown, are, however, nearly diagnostic. Positive diagnosis can only 

 be made by, the aid of the microscope and the detection of the parasite. If we 

 puncture one of the pustules, and mix its contents on a slide with a little water, 

 the acari are easily discovered. I have found as many as thirty to one pustule. 

 Sometimes we mav detect them on the root of a hair removed from an affected 

 spot. With a low power, the parasites somewhat resemble "sprats or minnows, but 

 a higher power shows them to consist of a head and body, which latter terminates 

 in a long and obtusely pointed tail. They are furnished with six or eight legs 

 situated on the anterior part of the body, three or four on each side. The head 

 consist? of two antennae and a median proboscis, all of which are capable of being 

 moved forward or backward. The legs consist of three segments. The movements 

 of the creatures are not often seen, and are very slow. The parasite measures 

 about one-hundredth of an inch in length by one five-hundredth in breadth." 



"In regard to treatment, Fleming, in "Veterinary Sanitary Science," says 

 "The situation of the Demodex renders it almost inaccessible to parasitical 

 remedies; the disease it engenders is therefore looked upon as extremely trouble- 

 some, and, in the majority of cases, almost beyond a cure. Often, when it is be- 

 lieved to be extinguished, it reappears in all its virulence in one or two months. 

 Nevertheless, Zurn asserts that he has frequently succeeded with an ointment 

 composed of 1 part of benzine to 4 parts of lard. Zundel states that the balsam 

 of Peru has often yielded good results when the malady has not been of too long 

 duration; he has employed it dissolved in alcohol (1 to 30)." 



