FORTY-FIRST ANNUAL CONVENTION 291 



ter of all exposed herds. It was then decided that the law re- 

 quired the Department to comply with the request of the Chicago 

 Serum Company for a test of the serum in order that if it were 

 found safe, it might be placed upon the market. The National 

 Serum Law gives the Department no authority to refuse to per- 

 mit the sale of a serum unless it is contaminated, dangerous, or 

 worthless. 



Arrangements were accordingly made by the Chicago Serum 

 Company for a test under the supervision of the Department. 

 Forty-one thousand cubic centimeters of the serum were thor- 

 oughly mixed and rebottled, and on June 30 samples were in- 

 jected into eight small hogs. Two check-hogs were also includ- 

 ed in the test. Although injections as large as 40 cubic centimet- 

 ers were used, it is certain that none of these hogs developed foot- 

 and-mouth disease. The test being thus absolutely negative — that 

 is to say no indications of the disease resulted from it — the com- 

 pany was informed that it could ship out the serum to its cus- 

 tomers. 



On August 8 the inspector in charge of field inspection at 

 Chicago telephoned to Washington that a case of foot-and- 

 mouth disease had been discovered in a herd which had been in- 

 oculated with this serum in Cook County, Illinois. Pending in^ 

 vestigation, all shipments of serum produced in Chicago were 

 at once prohibited. As a result of the investigation it was found 

 that serum from the Chicago Serum Company had been used on 

 eleven herds of hogs, eight of which were in Illinois and one 

 each in Minnesota, Michigan and Indiana. Inspection showed 

 that eight of these herds were infected with foot-and-mouth dis- 

 ease, although only a very small percentage of the hogs in them 

 manifested symptoms of the disease. All the animals were, how- 

 ever, slaughtered at once. The three herds in which no disease 

 was found were also slaughtered without waiting to see whether 

 they would subsequently develop the disease or not. This meas- 

 ure was necessary on account of the risk that the disease might 

 be spread by the animals while in the incubative stage. As a re- 

 sult of the precaution no further cases have been reported from 

 Michigan, Minnesota or Indiana. 



