CHAPTER XIII. 

 CONTAGIOUS DISEASES. 



C CONTAGIOUS disease is one that may be trans 

 mitted from one animal to another. To use a com- 

 mon expression, it is "catching." Transmission from 

 one animal to the other may be accomplished in three 

 ways: (1) by coming on actual contact, thus allowing the 

 disease germ to pass from the one to the other, (2) by com- 

 ing in contact with some object carrying germs because of 

 being in contact with the diseased animal, or (3) by breath- 

 ing or remaining in the air containing germs of disease. 



1. Contagious Pleuro-Pneumonia. 



This, as the name suggests, is an inflammation of the 

 lungs and their covering— the pleura. It was formerly more 

 common than at present. 



It was first noticed in Prussia in 1802, Russia in 1824, 

 England in 1841, and America in 1843. It is a very con- 

 tagious disease in cattle, but never affects other animals. If 

 an animal once gets over this disease it will never get it again. 

 When there is an outbreak it spreads very rapidly, by the 

 germs of the disease being carried about in different ways. 



Symptoms. — The first symptom is fever. The tempera- 

 ture goes as high as 105 degrees. The animal will remain 

 feverish for a week or so, s-nd also have a cough, as if from 

 a slight cold. After this there is inflammation of the lungs 

 and their covering. By listening at the sides you will hear 

 the peculiar grating sound that is heard in inflammation of 

 these parts. The animal breathes heavy and quick, falls off 

 rapidly in condition, refuses to eat, becomes hide bound, and 

 there is a discharge from the nostrils of a whitish color, which 

 has a very bad smell. The pulse runs up higher and becomes 

 weaker ; the nose is dry, and the animal lies on its breast bone 

 most of the time. Sometimes there is diarrhoea, then costive- 

 ness. The eyes become dull and the animal soon dies. When 

 one animal in a herd becomes affected with this disease the 

 whole herd will soon become affected and die, and if it is not 

 checked soon spreads all over the country. 



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