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Cattle Scab 825 
The itch gradually spreads along the back, sides, and 
down on the outside of the legs. It does not seem to 
occur on the inside of the legs, thighs, or the thin skin 
of the abdomen. In its early stages, the coat looks 
rough, the hair standing on end. The skin becomes 
scurfy, and, a gummy exudation from it forms a crust 
in the hair sometimes one-half an ineh thick. The 
hair then comes off, or is rubbed from the badly 
affected areas, leaving bald patches of thickened, eal- 
loused and wrinkled skin. These patches often show 
first and most prominently on the top of the neck, which 
looks like the neck of an ox that has been calloused 
from wearing a yoke. 
After the hair comes off, the parasites leave the part, 
the bald areas get well, and the hair starts to grow 
again. Animals suffering from this disease have a de- 
jected and debilitated appearance, and fall away rapidly 
in flesh. They eat but little, and expend a considerable 
amount of time and energy in licking and seratehing 
themselves. 
The itch spreads quite rapidly through a bunch of 
cattle, especially if tne general health of the animals is 
not good. Six or eight weeks after the introduction of 
an infested animal into a herd the disease is usually 
thoroughly disseminated. Thrifty, vigorous animals 
resist infestation much longer than others, and, when 
attacked, recover much more quickly under treatment 
than do unthrifty animals. The disease appears to 
spread by direct contact of the infested with healthy 
animals, the itch mites passing directly from one animal 
to another. It is also spread by means of posts, feed- 
