a) ae eee ne 
366 REPORT OF THE COMMISSIONER OF AGRICULTURE. 
INCUBATION OF THE DISEASRH. 
Our experiments have shown this to vary eveatly, though m the great 
majority of cases it terminated in from three to seven days after inoeu- 
lation. As shown in the table appended, one sickened on the first day, 
three on the third, two on the fourth, one on the fifth, two on the sixth, 
four on the seventh, and one each on the eighth and thirteenth days 
respectively. A comparison of these results with those obtained else- - 
where seems to show that we have reached the two extremes. Dr. Sut- 
ton, observing the result of contact alone in autumn, sets the period at 
from thirteen to fourteen days; my own observations in Scotland, in 
summer, indicated seven to fourteen days; Professor Axe, in London, 
in summer, concluded on five to eight days; Dr. Budd, in summer, four 
to five days; and Professor Osler, in autu ma, four to six da Lys. 
SYMPTOMS. 
The cases observed were of all degrees of severity, from a slight access 
of fever, with some loss of appetite, irregularity of the bowels, and alter- 
nations of heat and cold on the surface, to violent attacks, terminating 
fatally after eleven days’ illness. 
Harly symptoms.—In an average case, one of the earliest signs of ill- 
ness was an elevated temperature of the body, amounting to one or two 
degrees above the former indications furnished by the same animal. 
This qualification appears requisite, as the temperatures of healthy pigs 
were found to vary widely under different conditions of life. After act- 
ive exercise or excitement 104° I’. is not unfrequent, while in a close 
pen where they are quiet and still, 160° to 102° I’. is quite as common. 
On more than one occasion, when a pig got accidentally fixed in a nar- 
row space where he had barely room to stand, the temperature was re- 
duced to 99° and even 98° F. The body heat was raised by a hearty 
meal and lowered by abstinence. Generally a sudden rise of tempera- 
ture and saturation of the atmosphere with moisture led to an elevation 
of the body heat, in other cases a reduction of the temperature of the 
air led to the same phenomenon. (See table of Meteorological Observa- 
tions and Temperatures.) In connection with the rise of temperature 
there was generally a diffuse redness of the skin, with increased warmth, 
alternating with cold, especially in the ears , NOS, tail, and limbs. The 
pulse usually rose per -ceptibly, sometimes re aching 120 per minute, while 
the breathing was little if at all affected. The snout was often drawn 
back, giving a wrinkled or pinched appearance to the face; the move- 
ments were less active, sometimes decidedly stiff and slow; there was 
perceptible falling off in appetite, and the bowels were ustially costive. 
Disease at its height—The temperature rose in most cases to 105° FB. 
and exceptionally only to 107° or 1089 F. (Dr. Osler records 110° iB); 
to be followed after a variable length of time (three to twenty days) by a 
a descent to the natural standard, ¢ or even lower. The pulse also rose to 
120-180, and the flushes of heat on the skin were much more frequent and 
exireme. ' At the same time certain changes appeared in the skin, vary- 
ing greatly in degree in different cases, but which may be described as 
follows: 
First. A pink or searlet rash in spots averaging about one-tenth inch 
in diameter, but often becoming confluent so as to form an extended 
blush. Many such spots disappeared momentarily under pressure, show- 
ing that the minute blood-vessels were not yet completely bloc ked, but 
only dilated. Many, however, could not be even temporarily obliterated 
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