CHAPTER II. 

 CONTAGIOUS DISEASES. 



I. CONTAGIOUS PLEURO-PNEUMONIA. II. RINDERPEST OR CATTLE PLAGUE. 



IIL TEXAS FEVER, SPANISH OR SPLENIC FEVER. IV. CONTAGIOUS ECZEMA, 



FOOT AND MOUTH DISEASE OR EPIZOOTIC APHTHA. V. ANTHRAX. VL VA- 

 RIOLA VACCINAE OR COW-POX. VIL TUBERCULOSIS. VIII. CANCEROUS 



ULCERS AND OSTEO SARCOMA. IX. LUMPY JAW. X CONTAGIOUS ABOR- 

 TION OF CATTLE. 



I. Contagious Pleuro-Pneumonia. 



This is the most fatal and contagious of the diseases to which cattle are 

 subject, except rinderpest (a contagious enteric fever), which has never yet 

 gotten a hold in America, and Texas or Spanish fever (si)lenic fever). It 

 was first introduced into the United States in 1843, at Brooklyn, Loner 

 Island, by a cow that was purchased from the caj^tain of an English vessel, 

 and several times since then, at various other ports, in the bodies of im- 

 ported cattle. It spread more or less slowly through parts of New York, 

 Massachusetts, Pennsylvania, New Jersey, Maryland, Delaware, Virginia, 

 District of Columbia, Ohio, Illinois, Kentucky and Missouri. Through the 

 combined efforts of the Federal government, exerted through the Bureau 

 of Animal Industry, and the various state governments, it has been effectu- 

 ally stamped out by quarantining and slaughtering all cattle in infected 

 districts. This was done at an enormous expense, but it is the only way 

 of radically ridding the country of this most insidious disease. 



It is a contagious fever of cattle, with local inflammation of the pleura, 

 (the thin membrane lining the thorax and investing the lungs), and the 

 lungs, accompanied by great prostration, and in its more malignant forms 

 ending in death in a few days. It is, however, often slow in its develop- 

 ment, weeks, or even months elapsing during which the contagion works 

 in the system, before finally revealing its fatal symptoms. 



So terribly contagious is this disease, and so insidious in its spread, that 

 exposed cattle may be transported long distances before it breaks out. The 

 period of incubation is Very indefinite, ranging from eighteen days to two 

 months. It develops in different cattle in all degrees of severity from a small 

 focus of pneumonia, the size of a walnut, or a patch of pleurisy two inches in 

 diameter, to a complete consolidation of both lungs, or a pleurisy involving 

 every square inch of the lining of the chest. Mild cases appear to recover; 

 they will show all the signs of good health, will feed well, fatten fast, cows 

 will breed and give milk, as usual, but they do not recover; they simply 



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