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322 REPORT OF THE COMMISSIONER OF AGRICULTURE. = 
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severe weather of the past winter caused a great reduction in the num- 
ber of animals affected, the disease was not eradicated, nor did its 
fatality seem to be lessened. The spread of the infection from one herd 
to another was greatly diminished; but, in infected herds, where the 
malady was still prevailing when cold weather set in, there appeared 
but little difference in the rapidity of the transmission of the disease, 
from one animal to another, in the same herd. Dr. H. J. Detmers, V. 
S., of Chicago, who conducted his investigations and made his experi- 
ments in one of the worst infected of the many large hog-growing dis- 
tricts in Minois, writing under date of January 7th last, speaks as follows 
of the effects of severe frosts on the spread of the disease: 
Since my last letter the weather has continued extremely cold. Where I now am, 
in Lee County, some five or six miles west of Dixon, the thermometer indicated ‘at 
seven o’clock on the morning of January 2, 28° below zero, and on the next morning 
24° below zero. At present—to-day, yesterday and day before—the weather is a 
little milder. ‘To-day it tried to snow a little; otherwise the sky has been clear 
every day. The wind is, and has been, west, except yesterday afternoon, when it was 
almost due south. Swine-plague during this cold weather does not seem to spread 
either so readily or so rapidly from one farm to another as afew months ago; but as to 
its spreading from one animal to another in the saine’ herd in which it previously ex- 
isted no difierence can be observed. It seems to be just as fatal as in August, and its 
course, on the whole, is probably more acute, as severe affections of the lungs and of 
the heart are more frequent, a fact easily explamed in the habits of swine crowding 
together and lying on top of each other in their sleeping places when the temperature 
is very low. 
Dr. James Law, of Ithaca, N. Y., whose investigations were solely 
confined to experiments intended to further establish the contagious 
and infectious character of the disease, the period of its incubation, 
&c., confirms the statement of Dr. Detmers, 7. ¢., that the severe frosts 
of winter do not destroy the germs of the malady but simply retard 
their conveyance from one herd to another. In a letter of recent date, 
forwarded since his report was completed, Dr. Law says: 
I have demonstrated that the freezing of the virulent matter does not destroy its ac- 
tivity, and that the virus loses nothing in potency by preservation for one or two 
months closely packed in dry bran. The same may be inferred of all other situations. 
when it is closely packed and where the air has imperfect access. These two last 
points are of immense importance as bearing on the question of the preservation of the 
poison in infected pens and yards alike in winter and in summer, to say nothing of 
its possible conveyance in fodder, &c. The different modes in which the disease may 
be conveyed in the wet and dry condition, and in the bodies of rabbits, and probably 
sheep and other animals, speak in the strongest terms against keeping up the pro- 
© duction of the poison by preserving sick animals, unless where they can be secluded 
‘in thoroughly disinfected buildings in which even the air shall be constantly charged 
with disinfectants. 
In mest of the States in which investigations have been made, the 
examiners have found the symptoms and post-mortem appearances of 
the disease the same, and hence agree as to the propriety of desig- 
nating the affection under the head of a general disorder. Dr. Detmers 
uas, therefore, given the disease the name of ‘ Swine-plague,” and Dr. 
Law has named it ‘¢‘ Hog-fever.”. While either designation would seem 
to be eminently proper, that of ‘‘Swine-plague” will no doubt be gen- 
erally adopted. 
As in almost all general disorders, a certain variety of organs were 
fonnd affected and diseased. Marked changes and extrayvasations in 
various parts of the body were observed, and inflammation of the lungs 
and large intestines was usually present.. The heart, the pleura, the 
eyes, the epidermis, and many other important organs showed either 
slight or more serious affections, and in almost every case tested with 
the thermometer the temperature was found to be above normal heat 
