DISEASES OF CATTLE 295 



centers of disease scattered throughout the body than above described, 

 the carcass should be condemned as unfit for human food. 



ANTHRAX. 



Anthrax, or charbon, may be defined as an infectious disease 

 which is caused by specific bacteria, known as anthrax bacilli, and 

 which is more or less restricted by conditions of soil and moisture 

 to definite geographical localities. While it is chiefly limited to 

 cattle and sheep, it may be transmitted to goats, horses, cats, and 

 certain kinds of game. Smaller animals, such as mice, rabbits, and 

 guinea pigs, speedily succumb to inoculation. Dogs and hogs are 

 slightly susceptible, while fowls are practically immune. The va- 

 riety of domesticated animals which it may attack renders it one of 

 the most dreaded scourges of animal life. It may even attack man. 

 Of this more will be stated farther on. 



Cause. The cause of anthrax is a microscopic organism known 

 as the anthrax bacillus. In form it is cylindrical or rod-like, measur- 

 ing 1/5,000 to 1/2,500 inch in length and 1/25,000 inch in diameter. 

 Like all bacteria, these rod-like bodies have the power of indefinite 

 multiplication, and in the body of infected animals they produce 

 death by rapidly increasing in numbers and producing substances 

 which poison the body. In the blood they multiply in number by be- 

 coming elongated and then dividing into two, each new organism 

 continuing the same process indefinitely. Outside of the body, how- 

 ever, they multiply in a different way when under conditions un- 

 favorable to growth. Oval bodies, which are called spores, appear 

 within the rods, and remain alive and capable of germination after 

 years of drying. They also resist heat to a remarkable degree, so 

 that boiling water is necessary to destroy them. The bacilli them- 

 selves, on the other hand, show only very little resistance to heat and 

 drying. It has long been known that the anthrax virus thrives best 

 under certain conditions of the soil and on territories subject to 

 floods and inundations. The particular kinds of soil upon which 

 the disease is observed are black, loose, warm, humous soils, also 

 those containing lime, marl, and clay, finally peaty, swampy soils 

 resting upon strata which hold the water, or, in other words, are im- 

 pervious. Hence fields containing stagnant pools may be the source 

 of infection. The infection may be limited to certain farms, or 

 even to restricted areas on such farms. Even the Alps, over 3,000 

 feet above sea level, where such conditions prevail in secluded val- 

 leys, anthrax persists among herds. 



Aside from these limitations to specific conditions of the soil, 

 anthrax is a disease of world-wide distribution. It exists in most 

 countries of Europe, in Asia, Africa, Australia, and in our own 

 country in the lower Missippi Valley, the Gulf 'States, and in some 

 of the Eastern and Western States. It seems to be gradually spread- 

 ing in this country and occurs in new districts every year. 



Meteorological conditions also have an important share in de- 

 termining the severity of the disease. On those tracts subject to in- 

 undations in spring a very hot, dry summer is apt to cause a severe 

 outbreak. The relation which the bacillus bears to these conditions 



