528 Tuberculosis. 



Bartel, Fontes and others), can more easily give rise to the 

 pathological process, on account of their great numbers, than 

 is i^ossible in other organs. 



The great predisposition of tlie lungs for tuberculosis is further 

 emphasized by the fact that aerogenic infection results exclusively in 

 pulmonary ali'eetion. According to Neumann & Wittgenstein this pre- 

 disposition is explained by the absence of certain ferments which have 

 tlie power of splitting or reducing fat molecules. Baumgarten observed 

 the development of pulmonary tul)erculosis after the introduction of 

 small quantities of bacilli into the bladder of rabbits. Bartel saw pul- 

 monary tuberculosis develop after intraperitoneal infection. Schroeder 

 & Cotton produced pulmonary tuberculosis in cattle and swine by sub- 

 cutaneous infection at the tip of the tail. Vallee got the same result 

 after injection of a culture into the milk cistern of a cow's teat. In 

 the latter case not only the lungs but also the supramammary, the 

 abdominal and the broncho-mediastinal glands became involved. It is 

 important to note that intravenous or peritoneal infection of goats and 

 rabbits causes the development of isolated pulmonary tuberculosis with 

 the formation of cavities, especially when the susceptibility of these 

 animals was previously reduced. 



"VVeleminsky attempts to explain the frequent primary affeotion of tlie bronchial 

 lymph glands by the intimate relationship existing between these glands and the 

 entire lymphatic system. These glands constitute a sort of ' ' heart ' ' into which 

 lymph vessels from all directions pour their contents which are then carried through 

 the l>roneho-mediastinal trunk into the siTbclavian vein. The correctness of this 

 view has never been demonstrated as far as guinea pigs are concerned and, aa 

 to other animals, it is at best questionable. However, these glands are also readily 

 infected following intravenous or intraarterial injections of virus (Baumgarten). 

 It has been observed that in calves infection by these methods usually results in 

 the development of pronounced lesions of these glands as well as of the lungs 

 proper. 



In regard to the transportation of tubercle bacilli from Waldeyer's 

 ring Behring is of the opinion that they give rise to the first lesions 

 in the superior cervical glafids and then travel through the lymph ves- 

 sels to the bronchial glands and the lungs. In opposition to this view, 

 Bongert, Beitzke and Devrient point out that the lymphatic system of 

 the head and neck is entirely separate from that of the lungs and its 

 glands and that the bacilli from the diseased subparotideal and sub- 

 maxillary lymph glands pass from the great lympathic trunk into the 

 vena cava, thence, with the blood, to the lungs and the bronchial glands 

 (especially common in swine). The tonsils play no important role in 

 this process, especially not in cattle. With their abundant supply of 

 lymphoid cells they M'ould rather act as a protection. However, should 

 the bacilli successfully pass through them they would cause changes in 

 the retropharyngeal glands (Devrient). 



Isolated tuberculosis of the lungs and of the broncho-mediastinal glands in 

 cattle is frequently observed in abattoirs. Thus, in the abattoir of Budapest in 

 the years 1898-1901, of 46,092 cases of tuberculosis in cattle, 40,306 showed affection 

 of the lungs only, including the peribronchial and mediastinal glands. In about 

 one-third of the cases the lymph glands only were aflfectod ; tonsils and retro- 

 pharyngeal lymphatic glands in only 102 cases. Bongert found the latter glands 

 affected in 3 out of 1,200 cases, Devrient in 2 out of 1,400 cases. Rasmussen found 

 the tonsils affected in 52 out of 4,708 cases (1.1%) and the retropharyngeal 

 glands in 228 cases (4.8%). 



