CIRCULAR 338, U. S. DEPT. OF AGRICULTURE 



examined with the low powers of the microscope. TVhenever possible 

 this examination should be made by a competent veterinarian or 

 zoologist, as these mites are frequently difficult to detect. The 

 finding of the mites is sufficient to confirm the diagnosis of mange, 

 but failure to find mites, while it establishes a presumption that the 

 disease is not mange, does not prove the case, as the mites may be 

 overlooked or not reached by the scraping. 



Symptoms. — Sarcoptic mange affects dogs of all ages and all breeds. 

 It usually begins about the head and may spread over the entire body 

 in the course of a month. It appears first in the form of red points 

 which soon become papules or vesicles, most easily seen where the skin 

 is thin and without pigment, as on the abdomen. As the mite bur- 

 rows into the skin it causes irritation and there is an exudate of 



serum. As this constant flow 

 of serum dries it forms the char- 

 acteristic scab. Simultaneously 

 this irritation gives rise to itch- 

 ing, which becomes intense in 

 the presence of heat or after ex- 

 ercise, and the animal scratches 

 and rubs the affected portions 

 of the body. In doing so it 

 rubs off the scabs and opens up 

 sores. Bacterial infection of 

 these areas may add to the in- 

 flammation and injury resulting 

 from the presence of the mite 

 and the scratching. The hair 

 also may become matted and 

 fall out. There is evidently 

 more or less toxic absorption 

 from the mites or from the dis- 

 eased skin, as shown by a blood 

 reaction in the form of an eosino- 

 philia, a condition frequently 

 associated with parasitism, and 

 the presence of the toxins and 

 the loss of nervous energy due 

 to constant itching and irrita- 

 tion cause the animal to become 

 weak and thin. The skin may show large sores, and the mangy 

 or " mousy" odor becomes very pronounced. A general impairment 

 of digestion and other body activities follows and if the disease goes 

 unchecked the animal dies, usually in 2 or 3 months under conditions 

 favorable .to the disease. The term " mangy dog" as an expression 

 of reproach shows the general appreciation of the extremely pitiable 

 condition and apparent worthlessness of such an animal. 



Treatment. — A great aid in the treatment of mange is the use of 

 such measures as will build up the general health and resistance of 

 the animal. The dog should receive plenty of good nourishing food, 

 including a supply of meat suited to the animal's condition and the 

 amount of exercise it can take. Exercise and fresh air are important. 

 Delafond and Bourguinon have recorded the cure of sarcoptic mange 

 in the dog by suitable diet, exercise, fresh air, and hygienic measures, 



Figure 1.— The canine sarcoptic mange mite, Sarcoptes 

 scabiei canis. Ventral view. Female. Enlarged. 

 From Fiebiger, after Fuerstenberg. (Micron meas- 

 urements: Male, 190 to 250 long bv 140 to 180 wide; 

 female, 290 to 450 long by 230 to 350 wide.) 



