596 Tuberculosis. 



the other diseased, and the artificial rearing of the calves on nurse 

 cows or with sterilized milk is obviated. The herd may then be kept 

 permanently free by replacing the reactors with newly purchased ani- 

 mals that have been subjected to the tuberculin test, and repeating 

 the test annually in order to remove any affected animal that may 

 have gained an entrance to the herd. 



Where the separate maintenance of two herds and the artificial 

 rearing of the calves from the infected dams meets with insurmountable 

 objections a modified form of Bang's method may be applied. Thus, 

 if a herd is so badly infected that it is known in advance that only 

 a comparatively few animals would be found free from disease, the 

 tuberculin test of the adult animals may be dispensed with but applied 

 to the young stock and the calves reared with the same precautions 

 prescribed under the regular Bang method. As the healthy young 

 heifers drop their calves and, come into milk they may be used as a 

 nucleus to build up a new free herd to which nothing but healthy 

 cows are added, while the number of infected animals in the original 

 herd may be correspondingly reduced. 



Ujhelyi provides healthy nurse cows for the newly born calves or, 

 where necessity demands, leaves the calves with their infected dams 

 and subjects them to the tuberculin test when they are weaned, slaughter- 

 ing all reactors. (In this method the loss is somewhat greater than 

 in the former.) In this case the Bang method is strictly adhered to in 

 so far as separation of the herd into a free and an infected group is 

 concerned and in so far as all animals with clinical evidence of disease 

 are removed at once and slaughtered. This modification of Bang's 

 method may be practiced where the rearing of calves with sterilized 

 milk meets with insurmountable difficulties. It has the advantage that 

 calves remain free from diarrhea even when under the care of less 

 careful attendants. 



By means of this method Ujhelyi has succeeded in bringing about a considerable 

 reduction in the percentage of reactions in a number of large herds. Thus on the 

 estates of Ya&l, 8zeiit-Liszl6 and Martonv&sir in March, 1899, of 1,031 adult cattle 

 884 reacted (85.7%) of 626 head of yearlings 333 (53.3%) reacted, while in 

 September, 1903, of 898 adult cattle only 37 or 4.1% and of 710 yearlings only 19 

 or 2.6% reacted to the tuberculin test. On eight -other estates, at the beginning 

 of the campaign (1898-1902), of 1,715 cattle tested 1,011, i. e., 59% reacted while 

 a few years later (1904 and 1905) only 63 head, 3.0%, reacted. 



Method of Ostertag. Ostertag abandons the tuberculin test en- 

 tirely for adult animals and consequently also the separation of the 

 herd into reactors and nonreactors. He lays special stress upon the 

 importance of an early disposition of all cattle with so called open tuber- 

 culosis and the rearing of all calves with milk sterilized at 85° C. or 

 raw milk from cows free from tuberculosis. When the calves are 

 weaned they are subjected to the tuberculin test and the reactors are 

 slaughtered. In order to dispose of all cases of open tuberculosis at 

 the earliest possible opportunity affected herds are subjected every 

 six months to examination by a veterinarian and all suspicious cows 

 are removed at once. In addition to this the milk (of the individual 

 cows as well as the mixed product from the entire herd) is subjected 

 to periodical bacteriological examination as are also any morbid secre- 

 tions that may become evident. 



This method, which has been made obligatory in 182 herds of the East 

 HoUandish-Prussian Herd-Book Association since 1900 , and since then has been 

 introduced into other German districts, can hardly be expected to bring about a 



