300 WESTERN GRAZING GROUNDS AND FOREST RANGES 



ders where the animals have scratched till the flesh is 

 torn and a falling off of the hair until in extreme cases 

 the victims are almost bare all these conditions point 

 to the trouble. 



The disease, which has existed in the western ranges 

 for many years, did not reach any serious stages until 

 about ten years ago, being contagious but very slow in 

 spreading. Mange does not primarily cause the death 

 of cattle but simply cuts their vitality down and saps 

 their strength till they fall easy victims to bog holes 

 or hard winters. So long as the animals are in good 

 flesh they seem able to withstand the attacks of the 

 mites and the disease makes but little if any headway. 

 With the coining of a hard winter, short feed and long 

 storms, animals rapidly lose flesh, and then the mange 

 mites begin to thrive. 



Some veterinarians think that the mites are repulsed 

 by the excess of fat in the animals' skins and lie dor- 

 mant until this excess is lost, when they emerge from 

 their hiding places to feast on an already suffering 

 and debilitated animal. Thus it is that the disease may 

 exist in a herd for a long time and then during some 

 hard winter when the cattle lose flesh the mange makes 

 its appearance and the owner wonders where they 

 "caught" it. Western stockmen made no serious fight 

 against the mange until through shipping it had spread 

 all over the country west of the Mississippi River, espe- 

 cially on the eastern slope of the Rockies and out into 

 the great plains country to the east. Then the United 

 States Department of Agriculture took hold of it, and 

 in six years has been able greatly to reduce the in- 

 fected area and in some states has completely eradi- 

 cated it. Had the Government from the first secured 



