INFECTIOUS DISEASES OF CATTLE. 391 



official in charge of the district. In the work of the United States 

 Department of Agriculture a numbered metal tag was fastened to 

 each animal's ear, and index books were so arranged that with a 

 number given the owner could be at once ascertained, or from the 

 owner's name the cattle for which he was responsible could be at once 

 learned. In this way, if an animal was missing from a stable the fact 

 became apparent at once, or if one animal too many was found in a 

 stable the number in its ear would indicate where it came from. 



When pleuropneumonia is discovered by these means, the entire 

 herd should be slaughtered as soon as the formalities of appraisement 

 can be arranged. In country districts the carcasses should be buried, 

 as it is generally impracticable to dispose of them in any other way. 

 In city districts the animals may be taken to a slaughterhouse, with 

 such precautions as are possible to prevent dissemination of the con- 

 tagion. The animals should be slaughtered under the supervision of 

 an inspector. The healthy carcasses may be utilized for food, but the 

 blood, entrails, and all diseased carcasses should be heated to a tem- 

 perature equal to or above boiling water, and then used for the manu- 

 facture of fertilizers. 



The disinfection of premises should be thorough and should be car- 

 ried out by a trained corps of men employed for that purj)ose. The 

 floors of stables should be removed, the accumulations removed from 

 beneath them, the contents of haylofts should be destroyed, and the 

 woodwork and soil beneath the stables should be thoroughly drenched 

 with a solution of bichlorid of mercury, 1 part to 2,000 of water. 

 After the flooring is replaced the woodwork should be coated with 

 limewash, containing one- fourth pound of chlorid of lime to the gal- 

 lon of mixture. 



Usually in these cases the owners are dependent upon their herd of 

 cows for a living, and consequently it is difficult or impossible to 

 hold the stables vacant for any considerable period. In a majority of 

 instances cattle may be admitted at once to stables so disinfected, 

 without the reappearance of the disease. Occasionally, however, it 

 will reappear without apparent cause. For this reason the inspection 

 and other measures must be maintained in the infected district for six 

 months or a year after the last case of disease has been disposed of. 



Many people have objected to the slaughter of diseased and exposed 

 animals as an unscientific and expensive method of eradicating this 

 disease. To these it may be answered that it is the only method 

 which has ever proved successful, and that in the end it is much more 

 economical than temporizing measures. 



Inoculation has been adopted in many countries, and has undoubt- 

 edly lessened the death rate, but the disease is kept up and spreads 

 where this practice is allowed. For this reason it should be prohib- 



