312 PRINCIPLES AND PRACTICE OF MILK HYGIENE 



48. A second tuberculin test shall follow each primary test 

 after an interval of six months, and shall be applied in accord- 

 ance with the rules and regulations mentioned. Thereafter, 

 tuberculin tests shall be reapplied annually, but it is recom- 

 mended that the retests be applied semi-annually. 



49. Identification of Cows. Each dairy cow in each of the 

 certified herds shall be labeled or tagged with a number or mark 

 which will permanently identify her. 



50. Herd-book Record. Each cow in the herd shall be 

 registered in a herd book, which register shall be accurately 

 kept so that her entrance and departure from the herd and her 

 tuberculin testing can be identified. 



51. A copy of this herd-book record shall be kept in the 

 hands of the veterinarian of the medical milk commission under 

 which the dairy farm is operating, and the veterinarian shall 

 be made responsible for the accuracy of this record. 



52. Dates of Tuberculin Tests. The dates of the annual 

 tuberculin tests shall be definitely arranged by the medical milk 

 commission, and all of the results of such tests shall be recorded 

 by the veterinarian and regularly reported to the secretary of 

 the medical milk commission issuing the certificate. 



53. The results of all tuberculin tests shall be kept on file by 

 each medical milk commission, and a copy of all such tests shall 

 be made available to the American Association of Medical Milk 

 Commissions for statistical purposes. 



54. The proper designated officers of the American Associa- 

 tion of Medical Milk Commissions should receive copies of 

 reports of all of the annual, semiannual, and other official tuber- 

 culin tests which are made, and keep copies of the same on file 

 and compile them annually for the use of the association. 



55. Disposition of Cows Sick with Diseases Other Than 

 Tuberculosis. Cows having rheumatism, leucorrhaa, inflamma- 

 tion of the uterus, severe diarrhoea, or disease of the udder, or 

 cows that from any other cause may be a menace to the herd, 

 shall be removed from the herd, placed in a building separate 

 from that which may be used for the isolation of cows with 

 tuberculosis, unless such building has been properly disinfected 

 since it was last used for this purpose. The milk from such cows 



