182 DISEASES OF 



conditions of animal life are favorable, the females al- 

 ways outnumber the males. In this case nutrition is in 

 abundant supply. The eggs will retain their vital 

 properties from 1 day to 3 weeks, depending on the 

 temperature after removal from the body. Hence the 

 great liability of a recurrence from reinfection after 

 the parasites themselves have been destroyed. 



Symptoms. In all animals the invasion of this insect 

 causes intense irritation and prevents ordinary and 

 necessary rest. They lose condition and from frequent 

 rubbing will soon be covered with sores as the disease 

 will extend in various directions. In sheep, hard crusts 

 or scabs are soon formed over the spot where the para- 

 site is located. The loss from this disease is probably 

 not very serious in this country, except in the case of 

 sheep in which it is enormous. Many parts of this 

 country that are well adapted to raising sheep are al- 

 most entirely devoid of this very profitable animal be- 

 cause of the difficulty of preventing infection. Many 

 farmers in Kansas have informed me that the great 

 losses from scab in sheep have compelled them to 

 abandon an otherwise profitable industry. 



Treatment. In mange of the horse the affected 

 animal should be isolated. No grooming instrument 

 used on the infected animal should be used on the un- 

 infected ; neither should the same harness be used. 

 The affected horse should be clipped and kept at some 

 distance" from the stable and the hair burnt. The 

 horse should now be well covered with soft soap and 

 rubbed with the hand to soften the scabs. At the end 

 of 2 hours the animal should receive a thorough scrub- 

 bing with a brush and warm water, after which it 

 should be dried with whisks of straw or cloth, the latter 



