164 CONTAGIOUS DISEASES OF DOMESTICATED ANIMALS. 



Lafosse, Villeniin, Diipont, and Zaugger, in support of this, and ad- 

 vances the following- proposition : 



The morbific principle cau enter the system either by the respirator}- or digestive 

 apparatus. The inspired air and the forages and drinks can act as vehicles ; it may 

 also be transplanted by way of the generative, organs (coitus), or by wounds, accidental 

 or experimental. 



Instances of infection by cohabitation are (pioted from Stahl (to i 

 stud bulls by a newly bought tuberculous one of different blood); Ken- 

 iier (to cow and calf from tuberculous cow of different blood); Fischer 

 (heifer from tuberculous cow and 3 cows and o.\ from tuberculous cow 

 of alien blood) ; and Jaum (11 cows from a new tuberculous one); Ross 

 (4 cows from a new tuberculous one) ; and others by Viseu, Zundel, 

 Grad, Haushatter, Leutz, Huzard, Tessier, D'Arboval, Remj^, and 

 Hugues. Cases of infection through food are quoted from Jessen (calves 

 sucking si(;k cows, died in six to twelve months) ; Volkers, Lehnert'(2 

 pigs of healthy parents in one moutli after feeding unboiled inilk of sick 

 cows); Bromley, Walley, Fleming, Zippilius (calf sucking tuberculous 

 dam died of diarrhea with circular, belt like ulcers of small intestine) ; 

 Gerlach (many calves and pigs infected by milk of sick cows), &c. 



Transmission by coition is less detinite, but is inferred from the oc- 

 currence of tubercidosis in the womb. Fallopian tubes, and ovary of the 

 female (Adam), and the testicles of the male (Schlotterer), also from 

 the abortions in tuberculous herds. 



Of transmission hy raw surfaces, all the cases of experimental inocula- 

 tion are instances. Lydtin took lymph from lung affected with tuber- 

 cle and lung phigue, but carefully avoided any point where tubercle 

 could be detected, and avoided also the blood as far as possible. With 

 this he inoculated 10 cattle, 5 of which, when killed twenty-three days 

 later, showed numerous distinct miliary tubercles in the inoculative 

 swelling, and one tubercle in the right lung ; the remaining four showed 

 tubercles of older date in the lungs. 



Toussaint inoculated a tuberculous cow with cow-])ox, furnished by a 

 healthy heifer, and eight days later from the residtiiig cow-pox vesicles 

 inoculated four rabbits and a pig. All of the rabbits became tubercu- 

 lous in two months. 



In the field of the experimental transmission of tubercle, the work 

 has now been extensive and the results most convincing. Villemin, 

 Gerlach, Chauveau, Colin, Soujou and Court Paul, Giinther and 

 Harms, Eivolta and Peroneito, Bagge, Bollinger, Kohue, Semmer, l>ifti 

 and Verga, Bouley, Peuch, Aufricht, Toussaint, and others have con- 

 tributed in varying degrees to the solution of the question, and the 

 gran<l result attests indubitably the communicability of the disease. 



Giinther and Harms conveyed the disease to 5 rabbits by making 

 them breathe the expired air from tuberculous cows. Tappeiner con- 

 veyed it to dogs by diffusing the tuberculous si)Uta of man in spray in 

 the air thev breathed. 



