THE COURSE OF DISEASE
Each disease possesses its own peculiar characteristics, which are more or less conspicuous in each individual case. Then, too, some diseases develop quickly and end quickly. Others run a course of several weeks; and still others several months or even years. The first class is acute, the second chronic. In both kinds nature is at work endeavoring always to effect a cure; and, unless other complications arise, the result of improper food, bad sanitary quarters, bad air, or conditions not conducive to health, recovery will, in most cases, result. The great drawback to rapid recovery comes from the outside influences that counteract the curative processes of the body itself. Good nursing, good air, proper food, are back of rapid recovery.
Most diseases have been carefully studied, and their course of development has been mapped out. Our veterinarians know, in a general way, how fever acts in live stock. If an animal is inoculated with Texas fever germs, the veterinarian knows the course of the disease beforehand. In a general way, he knows when the fever will begin, how long it will last, when it will be at its highest point, and when it will disappear. He knows all of this, even before he makes the inoculation. Yet no disease invariably runs the same course in different individuals. In fact, the virulence of bacteria have much to do with the course; mild cases occur usually when the germ is weak, and severe cases when the germs are very virulent. This explains why some attacks of measles or Texas fever or hog cholera are more fatal than other attacks in other places, or at other seasons of the year.
Typical Courses the Rule.
—It is in rare cases only that a regular course is not followed by most diseases. Take an infectious disease. The period of incubation comes first; this follows up the infection. During this period, no change in the animal is observed. He seems well, acts well, and does his work well. Nevertheless, all the time, during this period of infection, the germs are developing, multiplying, gaining headway, and so entrenching themselves that illness and disorder will soon follow. The period of infection varies in different animals and in different diseases. It may take two or three weeks for development, or as few as two or three days.
Following the period of infection comes the period of eruption. At this stage the typical characteristics are observed. At the next step the disease reaches its height with the animal under its complete dominion. But only temporarily. If properly nursed and treated, with most diseases, the animal will pass through the period and recover.
The final stage is the period of improvement. The battle that has been waged between the body and the disease is now about ended. The disease germs have been routed and the body has been victorious. All that now remains is the clearing away of the débris. In this case it is scattered throughout the body system. The damage that has been done is to be repaired and left, if possible, as near to the original condition, as the nature of the disease will allow. The period of improvement will vary in different diseases and in different animals. Recovery may occur in a few days, in some cases, and in others weeks and months will be required. A change of feed or pasture or work is usually necessary if the most rapid recovery would be had. In some cases, nothing other than absolute rest will suffice.