BEPOET OF THE SECRETARY OF AGRICULTURE. 17 



agreed upon by the State authorities and the department, and the 

 owners later were paid the stipulated amount. The appraisal was 

 based upon the meat or dairy value of the animals. 



For a time the disease continued to appear in new territory and 

 new cases were found more rapidly than it was possible to dispose of 

 old ones. After months of vigorous work, however, *the outbreak 

 was brought under control, the spread of the disease was checked, 

 and there was a steady diminution in the number of cases. On June 

 18, 1915, the last herd known to be infected at that time had been 

 slaughtered and buried and the premises disinfected. 



Sources of infection. — The exact origin of this outbreak has not 

 been discovered, although there seems to be no doubt that the infec- 

 tion was introduced from a foreign country. An effort was made to 

 trace the source of infection of each diseased herd and the informa- 

 tion obtained has been classified. The principal means of transmis- 

 sion was the shipment of animals directly from public stockyards 

 (707 out of a total of 3,021 herds investigated) . Neighborhood visit- 

 ing caused infection of the next largest number (509) ; direct contact 

 with neighboring animals, of 346 ; animals brought from infected 

 stables or lots, of 285 ; creameries, of 269 ; and dogs, poultr}^, and 

 birds, of 146. 



The National Dairy Show herd. — The cattle exhibited at the 

 National Dairy Show in Chicago, October 22-31, 1914, consti- 

 tuted a special problem. Before its opening the local inspector 

 of the Bureau of Animal Industry warned the manager of the 

 danger of holding it because of the recent discovery of foot-and- 

 mouth disease. At the close of the show the department, as a pre- 

 cautionary measure, requested the State veterinarian- to detain the 

 cattle for a few days to determine whether they had become in- 

 fected. On November 1 one of the cows developed the disease, and 

 the herd immediately was placed under close quarantine by the State. 



This herd consisted of over 700 head of very valuable pure-bred 

 cattle. Their slaughter would have been a misfortune. The condi- 

 tions under which the animals were held made it possible to main- 

 tain a quarantine, and it was decided to try to save them. They 

 were confined in a brick building, where it was practicable to estab- 

 lish hospital conditions and to prevent ingress and egress of persons 

 and animals except under absolute coatroL All persons were pro- 



22814°— AGB 1915 2 



