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different organisms or germs. So that, in reality, the one has nothing 

 at all to do with the other ; the only similarity of importance being 

 perhaps that both are rapid and fatal in their effect. For the in- 

 formation of our German settlers we may mention that this disease 

 is known in their language as " Rauschbrand." 



CAUSE. 



Black-leg is a rapidly fatal infectious disease of young cattle 

 and is caused by a spore-bearing organism, the Bacillus Chaiivoei- 

 Spring and fall are said to be the most favourable seasons for the 

 development of the ailment, and cattle between the ages of six 

 and eighteen months are the most liable to become affected, al- 

 though partial susceptibility seems to remain up to about four 

 years. 



The manner of infection is by indirect contact with the germ on 

 infected soil, the organism gaining entrance to the body through 

 abrasions of the skin, and, perhaps, in rare cases, through the 

 mucuous membrane of the mouth and other parts of the alimen- 

 tary canal. The wounds or abrasions are generally quite minute 

 in size, but sufficiently deep to penetrate through the skin into 

 the tissues underneath. Punctured wounds, such as those received 

 from barbed wire fences or from stubbles or briers in pastures, 

 seem to be the most likely method of infection, and correspond 

 somewhat closely to the only manner in which the disease may 

 be produced artificially — viz., through injection of the virus hypo- 

 dermatically. 



SYMPTOMS. 



The disease is easy of recognition on account of the symptoms 

 being quite characteristic. It is characterized, first, by the symp- 

 toms of a more or less intense fever, and by the appearance of a 

 specific tumour, or swelling, upon the body, neck or upper part of 

 the limb above the knee and hock, causing stiffness or lameness. 

 This swelling is almost constantly found in the thick flesh or mus- 

 cles of the parts mentioned. It consists of a progressive inflam- 

 matory enlargement, of firm and uniform consistence, rapidly ex- 

 tending in area and depth, and later becoming insensitive, crepi- 

 tant and resonant, or in other words the swelling emits a crack- 

 ling sound when the hand is passed over it. This crepitant sourd 

 is due to the collection of gas in the affected flesh, and which is 

 produced by the germs of the disease. When the swelling is cut 

 into, a frothy, dark red fluid escapes, and the flesh of the swel- 

 ling is dark in colour, with the appearance of being mortified. 



With few exceptions, the disease terminates fatally, death 

 usually occurring in from twelve to thirty-six hours after the first 

 appearance of the symptoms. 



TREATMENT. 



With regard to treatment, it may be said that curative (.-') agents 

 are of little or no avail — prevention being the only satisfactory 

 method of attacking the disease. This may be divided into the 

 following, viz., hygienic and preventive or protective. 



