128 



FARMER'S CYCLOPEDIA OF LIVE STOCK 



particularly on hog cholera and swine 

 plague. It is perhaps best, in discussing 

 swine diseases, to start with the most 

 important infectious ones. 



Hog cholera — I n the corn belt, where 

 hogs are raised to the greatest extent, 

 hog cholera and swine plague are the 

 most discouraging troubles with which 

 the hog raiser has to deal. These diseases 

 may occur separately, or at the same 

 time, and it is often difficult to make a 

 diagnosis between them, partly for the 

 reason that the hog may be affected with 

 both diseases at the same time. In fact, 

 hog cholera and swine plague quite com- 

 monly occur in conjunction, spreading 

 through a herd of hogs and attacking 

 one animal after another. Hog cholera 

 has not been known for a long time, as 

 compared with anthrax or tuberculosis. 

 The disease was referred to in Ohio in 



Fig. 82 — POSITION ASSUMED IN HOG 

 CHOLERA 



1833 and in the southern states at about 

 the same time. The origin of hog chol- 

 era is not known. Some writers seem 

 to believe that it came with imported 

 hogs from England or the European con- 

 tinent. According to estimates based on 

 losses actually reported, it appears that 

 the swine industry suffers to the extent 

 of $10,000,000 to $25,000,000 annually 

 from the ravages of hog cholera. In 

 1896 the loss from hog cholera was esti- 

 mated at nearly $50,000,000. The num- 

 ber of hogs which die yearly from hog 

 cholera in Indiana alone varies from 

 200,000 to 900,000. 



Confounded with swine plague — In 

 the earlier investigations of this dis- 

 ease, it was much confused with swine 

 plague; in fact, swine plague and hog 

 cholera were supposed to be different 

 forms of the same disease. In typical 

 cases, ^ however, hog cholera affects the 

 intestines chiefly, causing ulcers in the 

 intestinal walls, and also manifests it- 

 self in the form of reddened, inflamed 



areas on the ears, throat, chest and 

 flanks. Swine plague, on the other hand, 

 is more likely to attack the lungs, caus- 

 ing a form of pneumonia, attended with 

 much coughing. 



■'^J^T' 



Fig. 83 — chronic hog cholera, show- 

 ing ulcers in large intestine 



Symptoms — Hog cholera may be de- 

 fined as an infectious, malignant disease, 

 due to the presence of the hog cholera 

 bacillus in the intestines. The most 

 conspicuous symptoms are loss of appe- 

 tite, high fever, discharge from the eyes, 

 reddish or purplish discoloration of the 

 skin and constipation followed by pro- 

 fuse diarrhea, which persists until the 

 death of the animal. The temperature 

 is usually from one to three degrees 

 above the normal. Affected swine ap- 

 pear dull and lie quietly in the corner 

 of the pen or yard, frequently huddling 

 together or hiding under the bedding. 

 The discharge from the eyes is at first 

 watery, but later becomes thick and 

 yellow. The gait is staggering and un- 

 certain. The symptoms vary greatly in 

 different cases, but if an outbreak of 

 disease occurs in a herd of hogs, with 

 symptoms resembling those just de- 



Fig. 84 — cholera ulcers in wall of 



HOG INTESTINE 



scribed and spreading rapidly through 

 the herd, the services of a qualified vet- 

 erinarian should be called at once and 

 measures taken to protect the healthy 

 hogs. 



The mortality from hog cholera ranges 

 from 80 to 90 per cent. In acute cases 

 the animals die within two or three days, 

 while in the chronic form the disease,. 



