14 The Colorado Experiment Station. 
are more numerous in the corrals and around the barns than on the 
ranges and in the pastures. 
Symptoms. 
The symptoms are of special interest to 1 the stockman since it is 
by these that he will recognize the disease and an early recognition 
is of the utmost importance. The ailing calf is first noticed to be 
dull and may refuse to take food. Often if food is taken it is only 
partially masticated and is not swallowed, but collects in the mouth 
m large masses, so that what appear to be large swellings of the 
cheeks are in reality caused by accumulation of food in the mouth. 
There will be drooling from the mouth and on opening, a particu¬ 
larly offensive odor will be noticed. In fact, this odor when once 
recognized is quite characteristic. A close examination will reveal 
ulcers varying in size from a pinhead to two or three inches in diam¬ 
eter. The ulcer is covered with a thick yellow cheesy mass, which 
adheres rather firmly to the underlying tissues. This mass will vary 
in thickness according to the length of time the disease has run. 
These ulcers are frequently found on the sides of the tongue and 
alongside of the molar teeth, but may be situated far back in the 
throat, thus rendering it impossible for the calf to swallow. 
The animal at this time will be found to have a high fever, the 
temperature varying from 104 to 107 F. There may or may not be 
diarrhoea present. Extreme weakness prevails, the calf sometimes 
dying within a few days after symptoms are noticed. In some in¬ 
stances, particularly if the disease continues for as much as two or 
three weeks, the lungs, liver and intestinal tract may show the ne¬ 
crotic patches. Without treatment very few cases recover, but most 
of those affected die in from three days to five weeks. 
Spread. 
The disease spreads rapidly throughout a herd, but does not 
spread readily from one farm to another. The probable reason for 
its rapid spread in a herd, is that all being subjected to the same 
conditions are equally liable to abrasions in the mouth at about the 
same time, so that if the organism produces disease in one animal, 
it will in a considerable percentage of those on the same feed. It 
seems probable that suckling calves often get the infection from the 
teats of the mother, that have been contaminated with manure. The 
organism has been proven to exist in the manure of many animals. 
The question of the transmissibility to other animals and to 
man naturally arises, and in this connection it has been definitely 
proven that the disease can be transmitted, artificially to pigs and 
lambs, as well as rabbits and guinea pigs. Since this organism is 
