i> 
VESICULAR STOMATITIS OF HORSES AND CATTLE 5 
lesions were confined to a single foot of the affected animal. The 
lesions consisted of a very large vesicle in the interdigital space, 
extending over its entire area. Other vesicles appeared around the 
coronet. In some of the affected feet observed there was consider- 
able separation of the horny from the deeper structures at the heels. 
The lesions of the feet were practically identical in appearance with 
those of foot-and-mouth disease, but, unlike them in the cases ob- 
served, were confined to one foot. Furthermore, only a very small 
roportion of affected animals had lesions of the feet, whereas in 
Pear und woath disease the feet, as well as the mouth, usually become 
affected. 
Immediately before or simultaneously with the appearance of the 
vesicles, the animal is usually depressed and there is present a rise of 
temperature, which rapidly subsides after the vesicles rupture. A 
more or less profuse flow of saliva follows, which dribbles from the 
lips and consists of a thin, stringy, or frothy fluid. Not infrequently 
the presence of salivation is the first indication that the animal is 
sick. Owing to the painful condition of the mouth at this stage, 
there is-loss of appetite or at least inability to eat, and in horses 
“ oritting ” of the teeth is quite frequent, while in cattle “ smacking ” 
noises are heard as in foot-and-mouth disease. This sensitiveness as 
a rule remains for several days, after which healing commences, and 
it is remarkable to observe how quickly the sick animals wili begin 
to eat even while their tongues are still eroded. Although eating 
well, they do not regain their original thrifty appearance for some 
time longer. In dairy cows in addition to shrinkage in flesh there is 
a noticeable reduction in the normal flow of milk for a few days. 
So far as observations of the writer are concerned, the period of 
incubation of vesicular stomatitis, following natural exposure, 
varied from 36 hours to 9 days, but the greatest number of cases 
occurred in from 2 to 5 days after exposure. Following inoculations, 
vesicles are seldom more than 48 hours in appearing, are usually 
present after 38 to 44 hours, and occasionally appear in 24 hours. 
The temperature begins to rise between the eighteenth and twenty- 
fourth hours and may reach 105° or even 107° F. in cattle. 
No losses have been reported from uncomplicated cases of this dis- 
ease in either horses, mules, or cattle. A certain proportion of 
horses and mules having vesicular stomatitis also became infected 
with either influenza or contagious pneumonia, or perhaps both, 
and some deaths have occurred among such animals. 
CONTAGIOUSNESS 
The degree of contagiousness varies between wide limits. In 
fact, certain writers have claimed that it is not contagious, because 
they fail to reproduce the disease after experimenting with only one 
healthy animal. ‘The writer’s experience with this disease shows 
that unless the inoculation is made from a freshly ruptured vesicle 
frequently one or even more of the inoculated animals in an experi- 
ment will fail to develop the infection, as in several instances the 
disease was produced in only 2 out of 3, or 2 out of 4, or, again, 3 out 
of 9 of the experimental animals; so that it is necessary to use more 
than one animal if accurate information is to be obtained. This 
