12 



fact in numerous sections hundreds of cattle had suddenly died and 

 certain estates had lost from a third to a half of their stock." 



The seriousness of the secondary lesions that follow this disease 

 may be understood from the following statement from the report 

 of the outbreak in Xew England in 1902 ( Report of Bureau of 

 Animal Industry, 1002) : 



"In Massachusetts a number of herds were preserved which 

 had the disease in a mild form and which had apparently recovered 

 at the time the inspection was made. In about one-third of the 

 cases where the owners afterwards came in with the statements that 

 relapses had occurred with their animals, some were again affected 

 with a formation of vesicles and most of those had abscesses in 

 the udders which made them unfit for milk production. At the time 

 these cattle were slaughtered the udders of many of them were so 

 distended with pus that they were ruptured as the animals fell and 

 discharged vast quantities of this liquid." 



In order to show that the general character of the disease is 

 not always mild it should be stated that it was not until 1 -- 7 r> that 

 it was classiHed in Denmark as a '•malignant, infectious disease." 

 It is now regarded in that country as one of the most harmful 

 diseases among domesticated animals, ami the greatest efforts are 

 now being made to keep it in check. 



In addition to the serious udder and feet trouble. Professor 

 Bang makes the further statement: 



''It may be added that in nearly all outbreaks some cows con- 

 tract inflammation of the udder, with the result that many of 

 these cows become more or less worthless for milking: some cows 

 get a malignant and persistent hoof complaint which weakens them 

 generally. Furthermore a number of young calves and pigs die. 

 as well as adult animals occasionally; abortion is also liable to 

 occur: and all this without taking into account the emaciation 

 caused by the disease. There is thus every reason for treating the 



disease and doing everything possible to prevent it> gaining firm 

 footing." 



It is important to understand the means by which this disease 



is disseminated. As already stated, it is one of the most infectious 



diseases of which we have knowledge. As the virus or •"seed" of 



the disease is discharged from the infected animal, it is readily 



understood that the diseased animal is the OlOSt important means of 

 Carrying the infection. It is also recognized, and very extended 



experiments by Professor I less, of Berne, Switzerland, prove that 



