856 CYCLOPEDIA OF LIVE STOCK AND COMPLETE STOCK DOCTOR. 



icated from the herd, a clean herd established, and the danger of its 

 spread to man removed. Tuberculin may, therefore, be considered a 

 most beneficial discovery for the stock raiser. Strange to say, many of 

 these men have been incredulous, antagonistic, or prejudi-ced against 

 the tuberculin test by misinterpreting published statements, by incor- 

 rect, unsubstantiated, or exaggerated reports, and by alleged injurious 

 effects to healthy cattle. 



Law has clearly stated the question when he says: 



Many stock owners still entertain an ignorant and unwarranted dread 

 of the tuberculin test. It is true that when recklessly used by ignorant 

 and careless people it may be made a root of evil, yet as employed by the in- 

 telligent and careful expert it is not only perfectly safe, but it is the only 

 known means of ascertaining approximately the actual number affected 

 in- a given herd. In most infected herds, living under what are in other 

 respects good hygienic conditions, two-thirds or three-fourths are not to 

 be detected without its aid, so that in clearing a herd from tuberculosis, 

 and placing both herd and products above suspicion, the test becomes 

 essential. 



********* 



In skilled hands the tuberculin test will show at least nine-tenths of 

 all cases of tuberculosis when other methods of diagnosis will not detect 

 one-tenth. 



It is perfectly natural that there should be objection to its use among 

 those who are not acquainted with its method of preparation or its prop- 

 erties; but it. is difficult to explain the antagonism of farmers who are 

 familiar with the facts connected with the manufacture and use of 

 tuberculin. Probably the most popular objection to tuberculin is that 

 it is too searching, since it discovers cases in which the lesions are small 

 and obscure. While this fact is admitted, it should also be borne in mind 

 that such a small lesion to-day may break down and become widely dis- 

 seminated in a relatively short period. Therefore any cow affected with 

 tuberculosis, even to a slight degree, must be considered as probably 

 dangerous not only to the other animals in the herd, but also to the 

 consumer of her products. 



V. The Harmlessness of Tuberculin. 



Furthermore, tuberculin must be considered as harmless for healthy 

 animals in view of the results revealed by numerous tests covering vast 

 numbers of animals. And it has also been clearly demonstrated that 

 tuberculin interferes in no way with the milking function in healthy 

 cattle; neither in the quantity of milk nor in butterfat value has any 

 variation been detected. 



Nocard and Leclainche state: 



