DISEASES OF ORGANS OF LOCOMOTION 



RHEUMATISM 



This is a painful condition affecting the organs of locomotion, 

 and may be either of one or two types. Articular rheumatism 

 is the more common form, and is associated with marked swelling 

 of the joints. Muscular rheumatism is more rare, and consists 

 principally in an inflammation of the structure of the muscle 

 itself, without any swelling of the joints. In the hog the two 

 conditions are frequently associated, and it does not appear 

 necessary to make any differential distinction between the two 

 forms of the disease. 



Causes. — The hog is raised under such conditions as are par- 

 ticularly likely to produce rheumatism, but for some reason the 

 animal seems to have considerable resistance against the disease, 

 as rheumatism is much less common than would be expected among 

 swine. The articular form of rheumatism is undoubtedly a germ 

 disease and is produced by infection of the blood, and through the 

 blood the joints, by some specific germ. Keeping animals in cold, 

 damp pens, and exposure to wet and cold are important predispos- 

 ing causes, in that they lower the resistance of the animal to and 

 make it easy for the germs to enter. Overheating followed by 

 exposure to chilling winter winds is especially liable to cause an 

 attack. Overfeeding and excessive exercise may be followed by 

 the muscular type of the disease. Dipping of hogs in cold, damp 

 weather may set up an attack of the disease. 



Symptoms. — The s^nnptoms of acute articular rheumatism are 

 very pronounced and quite easily made out. The animal has a high 

 fever, loses appetite, and develops a most severe painful lameness. 

 In the articular type this lameness is associated with large painful 

 swellings of the hock, knee, and joints of the feet. These swell- 

 ings show a tendency to change location, and one day the hock may 

 be affected and the next day the knees and the feet. This tendency 

 to shift about is very characteristic of rheumatism. 



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