INFECTIOUS DISEASES. 515 
valescence; or, in an unfortunately large number of cases, the course 
of the disease is complicated by local inflammatory troubles, whose 
gravity is greater in influenza than it is when they occur as sporadic 
diseases. 
Complications—The complications are congestions, followed by 
inflammatory phenomena in the various organs of the body, but they 
are most commonly located in the intestines, lungs, brain, or vascular 
laminz of the feet. Atmospheric influence or other surrounding 
influences of unknown quality seem to be an important factor in the 
determination of the local lesions. At certain seasons of the year, 
and in certain epizootics, we find 40 and 50 per cent or even a greater 
percentage of the cases rendered more serious by complication of the 
intestines; at other seasons of the year, or in other epizootics, we find 
the same percentage of cases complicated by inflammation of the 
lungs, while at the same time a small percentage of them are com- 
plicated by troubles of the other organs; inflammatory changes of 
the brain, of the laminz, more rarely commence in epizootic form, 
but are to be found in a certain small percentage of cases in all 
epizootics. 
Exciting causes are important factors in complicating individual 
cases of influenza, or in localizing special lesions, during either enzo- 
otics or epizootics. These exciting or determining causes act much 
as they would in sporadic inflammatory diseases, but in this case we 
find the animal much more susceptible and predisposed to be acted 
upon than ordinary healthy animals. With a temperature already 
elevated, with the heart’s action driving the blood in increased 
quantity into the distended blood vessels, which become dilated and 
lose their contractility, with a congestion of all the vascular organs 
already established, it takes but little additional irritation to carry 
the congestion one step further and produce inflammation. 
Complication of the intestines ——When any cause acts as an irri- 
tant to the intestinal tract during the course of this specific fever it 
may produce inflammation of the organs belonging to it. This cause 
may be constipation, which can find relief only in a congestion which 
offers to increase the function of the glands and relieve the inertia 
caused by a temporary cessation of activity; or irritant medicines, 
especially any increased use of antimony, turpentine, or the more 
active remedies; the taking of indigestible feed, or of feed in too 
great quantities, or that has been altered in any way by fungus or 
other injurious alterations; the swallowing of too cold water; or any 
other irritant may cause congestion. This complication is ushered 
in by colics. The animal paws with the fore feet and evinces a great 
sensibility of the belly; it looks with the head from side to side, and 
may lie down and get up, not with violence, but with care for itself, 
perfectly protecting the surface of the belly from any violence. At 
