430 DISEASES OF CATTLE. 



oa tuberculin injection I reported two cases in which acute miliary tuberculosis 

 was proved in two high-grade tuberculous cows several weeks after the tuber- 

 culin injection. I then stated my suspicion that perhaps the tuberculin injec- 

 tion had some connection with this, just as is often supposed to be the case 

 in human practice. With my present very large amount of material for obser- 

 vation at hand I may express the following opinion : Such an acute develop- 

 ment of tuberculosis as a result of tuberculin injection is to be feared only 

 exceptionally, and then in cases of advanced tuberculosis. It must iwt be for- 

 gotten that acute miliary tubei-culosis by no means rarely accompanies an 

 advanced tuberculosis of long standing. It is therefore impossible to offer 

 strict proof of the causal connection with the injection, and only oft-repeated 

 observation could mal^e this probable. In support of my view I offer the 

 following: In the course of the last three years I have made careful post- 

 mortem examinations of 83 tuberculous animals, which have been removed 

 from my experiment farm, Thurebylille. Among these were 18 (or, strictly 

 speaking, 23) high-grade tuberculous animals. I have been able to prove 

 miliary tuberculosis in only 4 of these. Among the others, which showed less 

 developed tuberculosis, I have never found miliary tuberculosis, and with 

 very many I have never found any sign of a more rapid development of the 

 process. On the contrary, it has been proved that the disease was restricted 

 locally, often for years, in spite of yearly rei^eated injections. Dissections were 

 made at very different periods after the injections — in 17 cases from 4 to 12 

 days after the last test. In all of these cases earlier tests had been made 

 months or years before. In 28 cases the injection took place from 19 days 

 to 2 months before the butchering; in 3 of these cases earlier injections had 

 been made. In 38 cases from two and one-half months to one year intervened 

 between the last injection and the dissection. Dissection gives the best expla- 

 nation of this question, but a clinical observation, continued for years, of a herd 

 tested with tuberculin can render very essential aid. If Hess's opinion is cor- 

 rect, it is to be assumed that tuberculosis must take an unusually vicious 

 course in such herds, but this I have been unable to prove. At Thurebylille 

 there has existed for three years a reacting division, consisting originally of 

 131 head and now of 69. Although these animals are yearly tested, and 

 although most of them react every year, the division certainly appears to be 

 made up of healthy animals, and the farm inspector has expressed the decided 

 opinion that the tuberculosis in this division is no more developed than at the 

 beginning of the experiment. The testimony of many owners of large herds 

 of cattle which have long ago been injected is to the same effect. I will 

 adduce statements from several. A farm tenant whose cattle were injected 

 20 months previously, when 82 per cent of the grown animals reactetl, wrote 

 me recently as follows : " Only 2 cows from the division of 100 head had been 

 sold as decidedly tuberculous. The majority appeared afterwards, just as 

 before, entirely healthy. The fat animals which had been slaughtered had 

 been pronounced healthy by the butchers." Another farm tenant with a herd 

 injected in 1894 had not been obliged to remove a single animal from the tuber- 

 culosis division, numbering 70 head. A large farm owner in Jutland stated 

 in September that he had traced no undesirable result from the injection. His 

 herd of 350 had been injected in February and about 75 per cent reacted. 

 Similar answers have been given by other owners and veterinarians. 



A veterinarian who had injected 600 animals, among them a herd of a large 

 farm, 18 months previously, expressed the belief that the injection had pro- 

 duced in no single case an unusually rapid or vicious course of tuberculosis. 

 In spite of a demand made months ago, I have received thus far no report from 

 any veterinarian of an undesirable result. 



