442 THE MANAGEMENT AND FEEDING OF CATTLE 



all conditions; third, because there is practically no in- 

 formation up to the present in regard to the method of 

 infection or spread ; fourth, because it is increasing in 

 the United States and is very frequently fatal ; fifth, 

 because no method has yet been discovered that will 

 protect from it or lessen its virulence; and, sixth, be- 

 cause it sometimes disappears as quickly as it came. 

 The extent to which it is now being studied by the most 

 skilled among veterinarians will doubtless soon throw 

 much light upon what is now so little understood. 



The specific cause is apparently a germ (Bacillus 

 boviscpticus), which, it is thought, belongs to the same 

 group of baccilli as those which produce swine plague 

 and chicken cholera. In the various forms of the disease, 

 there is more or less of a resemblance to anthrax, black- 

 leg, and cerebro-spinal meningitis, but competent 

 veterinarians can correctly diagnose the disease by the 

 difference which characterizes the symptoms. But the dif- 

 ferences manifest in post-mortem examinations are much 

 more pronounced. It is supposed that the germs reach 

 the animal through inoculation by means of abrasions 

 in the skin, by injury to the mucous membranes from such 

 materials as coarse fodders or through the membranes 

 of the respiratory organs. It seems to occur most fre- 

 quently in swampy areas and in pastures subject to over- 

 flow, and also in cornstalk fields. It is said to occur 

 more frequently in the spring when subterranean waters 

 l)y accumulation are forced to the surface and bring with 

 them harm-laden bacteria. Other authorities believe 

 that conditions of climate and season have nothing to do 

 with the prevalence, virulence, or disappearance of the 

 disease. 



Three forms of the disease have been recognized, 

 based upon the distribution of the lesions, that is, the 

 morbid changes in the structure or functions of the 

 organs or tissues. These are the superficial or cuta- 

 neous, the pectoral or thoracic, and the intestinal. Among 



