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When cholera begins in a herd the hogs do not all become sick at once, 

 but, on the contrary, only one or two will refuse to come up to feed' with 

 the herd. They will remain hidden in the nest, and when driven from the 

 bed their backs may be arched and they may appear cold and shiver. The 

 balance of the herd may remain apparently well for several days, when 

 others are likely to be found affected in about the same way as those first 

 attacked. As the disease progresses, the sick hogs become gaunt or tucked 

 up in the flank, and have a weak staggering gait, the weakness being most 

 marked in the hind legs. 



If the lungs are effected there may be a cough which is particularly 

 noticeable when the hogs are disturbed. The eyes usually are inflamed and 

 show a whitish discharge, which may cause the lids to stick together. 



Constipation, which is commonly present in the early days of the disease, 

 is generally followed by a diarrhoea. As the disease reaches its height, 

 red or purplish blotches are likely to appear upon the skin of the ears, of the 

 belly, and of the inner surfaces of the legs. 



Some of the symptoms mentioned may be present in other diseases, 

 but the owner should remember that cholera spreads rapidly through a herd, 

 and too much time should not be lost in undertaking to distinguish it from 

 some other disease. 



The temperature of the hogs is of such importance in diagnosing cholera. 

 The normal temperature in ordinary weather when the hogs are not excited 

 or worried will range from 101 to 104F., but when cholera is present it 

 is not uncommon to find a large proportion of the hogs with temperatures 

 from 104 to 107, and even higher. 



The important changes found in the carcass after death from hog cholera 

 are as follows: 



1. Purple blotches on the skin. 



2. Blood-colored spots on the lungs, on the surface of the heart, on 

 the kidneys, and on the outer surface and inner linging of the intestines 

 and the stomach. 



3. Reddening of the lymphatic glands. 



4. Enlargement of the spleen, in acute cases. 



5. Ulceration of the inner lining of the large intestine. 



Any one or all of these changes may be found in a hog which has died 

 from hog cholera. It is rare to find all in any one case. In the lingering 

 or chronic cases of hog cholera it is usual to find the intestinal buttonlike 

 ulcers, while the blood-colored spots described above are, as a rule, found 

 only in the acute cases. 



HOW THE DISEASE IS SPREAD. 



Hog cholera destroys about 90 per cent of all hogs that die from disease. 

 It is an infectious disease, due to a specific cause, hog cholera virus. The 

 virus is known to develop only in the body of hogs. Therefore, the sick 

 hog must be considered the primary source of danger to a community. Hog 

 cholera virus is eliminated from the sick animal in the urine, faces, and 

 secretions of the eyes and nose. The blood of sick animals also contains 

 the virus, so that the entire carcass of a hog dead from cholera is dangerous. 



With this knowledge at hand, any attempt to prevent the spread of the 

 disease must be directed towards the infected animals and such objects as 

 may become contaminated with his excretions. 



Transportation of hogs, especially by rail, has resulted in the almost 

 universal infection of stock cars and public stock yards. This offers an 

 excellent opportunity for spreading infection over large areas. Stock hogs 

 being shipped to various localities, having their natural resistance lowered 

 due to the exposure of shipment, become easy victims of the germs of hog 

 cholera, which may be present in the stock yards or stock cars. Even 

 though the hog itself does not become infected while in these cars or yards, 

 other objects to which manure, bedding or dirt may adhere can carry this 

 infection. Such infected material may cling to wagon wheels, feet of men 

 and horses engaged in hauling or driving the hogs to the farm and although 



