Bovine Tuberculosis 689 



coming from animals that are diseased. The extermination of 

 bovine tuberculosis, therefore, becomes imperative, and the utmost 

 efforts should be made to bring it about. Several separate meas- 

 ures must be considered: 



1. Improvement in the methods of diagnosis, by which the 

 recognition of the disease is made possible before its ravages are 

 great. This is rapidly coming about with increasing information 

 regarding the use and abuse of tuberculin, etc. 



2. Means by which infected animals shall be destroyed. Here 

 the municipal and state governments furnish inadequate funds to 

 make possible the destruction of diseased cattle without adequate 

 compensation — an injustice to the unfortunate owner. 



3. Means of preventing the infection of healthy animals. In 

 many places this is being achieved with brilliant success by sep- 

 aration of the herd, healthy and newly born animals constitut- 

 ing one part, suspicious animals the other. By these means valuable 

 breeding animals can be kept for a time, at least, in usefulness. A 

 second and less successful means of preventing infection is by means 

 of prophylactic vaccination of the healthy animals with dead 

 cultures, modified living cultures, or by bacterio toxins made by 

 comminuting them. 



Experiments of this kind have been conducted by McFadyen,* 

 on a large scale by von Behring.f by Pearson and Gilliland,t Cal- 

 mette and Guerin,§ and by Theobald Smith, || all of whom think 

 distinct resisting power against infection by the tubercle bacillus 

 can thus be brought about. 



Tuberculin Test for Tuberculosis of Cattle. — The febrile reac- 

 tion caused by the injection of tuberculin into tuberculous animals 

 is an important adjunct to our means of diagnosticating the disease. 

 For the recognition of tuberculosis in cattle it is easily carried out. 



To make a satisfactory diagnostic test the temperature of the 

 animal should be taken every few hours for a day or two before the 

 tuberculin is administered, in order that the normal diurnal and 

 nocturnal variations of temperature shall be known. The tuber- 

 culin is then administered by hypodermic injection into the shoulder 

 or flank, and the temperature subsequently taken every two hours 

 for the next twenty-four hours. A reaction of two degrees beyond 

 that normal to the individual animal is positive of tuberculosis. After 

 one reaction of this kind the animal will not again react to an equal 

 dose of tuberculin for a number of weeks. 



* "Jour. Comp. Path, and Therap.," June, 190 1. 



f'Beitrage zur experimentellen Therapie," igo2, Hft. 5. 



t"Jour. of Comp. Med. Vet. Archiv," Nov., 1902, "Univ. of Penna. Med. 

 BuU.," April, 1905. 



§"Ann. de I'Inst. Pasteur.," Oct., 1905, May, 1906, and July, 1907; and 

 "International Congress on Tuberculosis," Washington, igo8. 



II "Journal of Medical Research," June, 1908, xviii, No. 3, p. 451. 



