SKIN DISEASES. 343 



fore never breed from either a dog or bitch attacked by this form 

 of eruption. There is considerable thickening of the skin, with 

 an offensive discharge from the surface, chiefly flowing from the 

 cracks and ulcerations under the scabs on it. This dries and falls 

 off in scales, taking with them a good deal of the hair, which is 

 further removed by the constant scratching of the poor dog, who 

 is tormented with incessant itching. Generally there is a fat 

 unwieldly state of the system for want of exercise, but the appe- 

 tite is often deficient. Clear the bowels with a brisk aperient, 

 such as (12) or (13). Give low diet without flesh, starving the dog 

 until he is ready to eat potatoes and green vegetables, alternately 

 with oatmeal porridge in moderate quantities. As soon as the 

 stomach is brought down to this kind of food, but not before, 

 begin to give the liquor arsenicalis with the food, the dose being a 

 drop to each four pounds in weight of the animal. A dog of 

 eight pounds weight, for example, will require two drops, three 

 times daily ; taking care to divide the food into three equal por- 

 tions, and not to give more of this altogether than is required for 

 the purpose of health. The arsenic must be administered for 

 weeks or even months. As soon as the itching abates, and the 

 health is improved, the mangy parts of the skin may be slightly 

 dressed with small quantities of sulphur and pitch ointments, 

 mixed in equal proportions. In two or three months the blood 

 becomes purified, the eruption disappears, and the health seems 

 impaired, a stomachic or tonic, (59) or (62), will often be required. 

 Sometimes the ointment (5Sa) will be necessary. 



Virulent mange, similar to psora and porrigo in the human sub- 

 ject, is of two kinds, one attributable to a parasitic insect, and the 

 other of vegetable origin. In the former case, which is its most 

 common form, it appears in large, unclean, unkempt kennels. The 

 disease is highly contagious. The skin is dry and rough, with 

 cracks and creases, from some of which there is a thin ichorous 

 discharge when the scabs are removed. The dog feeds well, but 

 from want of sleep is languid and listless ; likewise shows thirst 

 and some feverishness. The treatment of this form of mange is 

 based upon a belief that it is caused by an insect of the acarus 



