YO ANNUAL REPORTS OF DEPARTMENT OE AGRICULTURE. 



anti-hog-cholera serum. Representatives of the department visited 

 a total of 15,560 farms for the purpose of making investigations, 

 diagnosing disease, and giving advice regarding control and eradica- 

 tion. Two thousand and fifty-six meetings were held, at which 

 100,190 farmers and others were present to receive information con- 

 cerning regulations, quarantine, and measures necessary to combat 

 cholera successfully. Two thousand two hundred and thirty-six 

 farms on which the disease was found were either cleaned and dis- 

 infected or measures were taken to prevent the infection from reach- 

 ing neighboring premises. 



A special feature of the work of the year has been the successful 

 efforts in enlisting the support and cooperation of practicing veteri- 

 narians in the control and suppression of hog cholera, resulting in 

 uniform methods of treatmxent and moderate charges to farmers for 

 professional services in this line of work. 



State-wide educational and demonstrational work against hog 

 cholera has been conducted in cooperation with the extension divi- 

 sions of agricultural colleges in Alabama, Arkansas, California, 

 Florida, Maryland, and Tennessee. In these States the activities of 

 bureau veterinarians have been limited to lectures, demonstrations in 

 the use of serum, general instructions to county agents, farmers, and 

 swine growers on the subject of hog cholera, and taking part in cam- 

 paigns arranged by the colleges to bring to the attention of farmers 

 the possibility of reducing losses by the proper administration of 

 serum. In some of these States work of this character has progressed 

 to the point of action being taken to substitute intensive activities, 

 supported by the regulatory authorities, for the control of the disease 

 in restricted areas. 



VIRUS-SERUM CONTROL. 



The preparation and importation of viruses, serums, toxins, etc., 

 for the treatment of domestic animals are supervised and regulated 

 under the law of 1913. At the close of the fiscal year there were 89 

 firms licensed by the Secretary of Agriculture to maintain establish- 

 ments for the preparation of such products for sale in interstate com- 

 merce, and 2 firms held permits for the importation of products pre- 

 pared in 8 foreign laboratories. These licenses covered 135 different 

 products. One license was suspended and two were revoked during 

 the year. 



Virus and serum for use in the prevention of hog cholera form a 

 large part in volume of the products supervised. The anti-hog- 

 cholera serum produced by licensed establishments during the year 

 amounted to 238,861,279 cubic centimeters of which 5,036,875 cubic 

 centimeters was destroyed by direction of bureau inspectors as be- 

 ing unfit for use. There was also prepared 68,813,983 cubic centime- 

 ters of hog-cholera virus for use in hyperimmunization of pigs for 

 the production of serum and 8,847,196 cubic centimeters for use in 

 conjunction with serum in preventive treatment. Of the former, 

 3,262,756 cubic centimeters was destroyed as being unsuitable for use, 

 while 1,183,271 cubic centimeters of the latter was withheld from the 

 market by the inspectors. To determine the purity of these products 

 1,064 tests of the virus and 2,167 tests of the serum were made on 

 calves, and to determine the potency of the serum 3,642 tests were 



