THE MILK SITUATION IN THE DISTRICT OF COLUMBIA. 151 



ing all cattle in the District of Columbia 321 reacting animals were slaughtered 

 and lesions of tuberculosis were found on post-mortem examination in all but 

 5, the percentage of accuracy being 98.44. Laboratory experiments were made 

 by the Bureau of Animal Industry during the past year in testing by microscopic 

 examination and animal inoculation the glands of cattle which had reacted to 

 the tuberculin test, but in which lesions were not found by ordinary post- 

 mortem examination ; and in more than half of the cases tubercle bacilli were 

 positively identified. This shows that tuberculosis was really present in these 

 carcasses, but in an incipient form, the lesions being too slight for detection 

 by ordinary post-mortem examination. It therefore seems that the percentage 

 of accuracy of the tuberculin test is even higher than is indicated by the 

 figures above given. (Chief Bureau of Animal Industry.) 



I agree with resolution No. 2 of International Commission of American 

 Veterinary Medical Association that " tuberculin properly used is an accurate 

 and reliable diagnostic agent for the detection of active tuberculosis in cattle. 

 (Surgeon General U. S. Army.) 



In 97 per cent of those giving a positive reaction tuberculosis has been found 

 to be present. ( Surgeon General U. S. Navy. ) 



The tuberculin test is a very reliable means of determining active tubercu- 

 losis in cows tested. (Surgeon General Public Health and Marine-Hospital 

 Service.) 



Very reliable when test temperatures taken for 18 hours after injections, and 

 all cattle showing either doubtful or typical reactions are removed. Even 

 slight rises of temperatures which rise and fall gradually are very suspicious, 

 e. g., 101.6, 101.9, 102.2, 102.3, 101.8, 101.7, 101.4. (Dr. William H. Park, New 

 York, N. Y.) 



If the source of the cattle is known and recent tuberculinization has not been 

 made, the tuberculin test is almost infallible in the hands of an expert inspector. 

 (Dr. Henry L. Coit, Newark, N. J.) 



A positive result is of great value. A negative result of less value. (Dr. 

 R. G. Freeman, New York, N. Y.) 



Within 3 per cent. Long series carefully done show better than this. (Dr. 

 M. P. Ravenel, Madison, Wis.) 



Under the following conditions I consider the tuberculin test practically 

 infallible: Use United States Department of Agriculture tuberculin. The 

 animal must show a normal range of temperature preceding the injection of 

 tuberculin and must be kept in a normal, quiet condition during the entire 

 test. It is very important that the animal to be tested has not been tampered 

 with before or during the application of the test, as many unscrupulous owners 

 prepare their animals by the different methods that do defeat the object of the 

 test. A great deal of criticism heard as to the unreliability and absence of 

 uniform results of the tuberculin tests can be attributed to the fact that the 

 animal to be tested has been tampered with prior to the application of the 

 test. The veterinarian applying the test should have had a large experience 

 in animal temperatures. He should have had experience with temperatures 

 and physical symptoms presented by animals that have been tampered with, or 

 in other words, doped. He should be familiar with the high temperature that 

 occasionally appears from causes other than the reaction due to the presence 

 of the tuberculin, which appears at a time he expects a typical tuberculous 

 reaction. This oftimes causes confusion to the veterinarian of little experience. 

 (Dr. T. A. Geddes, Kensington, Md.) 



Practically always. (Health officer Ann Arbor, Mich.) 



I do not know. (Health officer Baltimore, Md.) 



In our application of the test all reacting animals showed tubercular 

 lesions on post-mortem. Statistics compiled by investigators give 98 to 99 

 per cent positive when tests are applied by competent men. (Health officer 

 Birmingham, Ala.) 



Nearly all infected animals react, especially those with active disease. 

 (Health officer Bismarck, N. Dak.) 



Infallible if properly applied with reliable tuberculin. (Health officer Cleve- 

 land, Ohio.) 



Successful and dependable in 97 per cent of cases in experienced hands. 

 (Health officer Columbus, Ohio.) 



Negative except in tubercular cases. (Health officer Detroit, Mich.) 



Yes. (State board of health, Florida.) 



I have not had enough experience with it to say. (Health officer Jackson- 

 ville, Fla.) 



