Anatomical Changes. 545 



In horses, especially in young animals, the mesenteric and 

 retropharyngeal lymph glands are most frequently affected 

 (phthisis mesaraica). The affected glands may be white and 

 moist on section and resemble lymphosarcomata or their in- 

 terior may consist of a soft muco-caseous mass. In exceptional 

 cases there is calcification. They may represent masses of 

 tumors firmly enclosing large vessels (e. g. the posterior vena 

 cava and portal vein) ; they may involve the vessel walls or 

 have grown into their lumen producing thrombi (Lustig), or 

 leading to generalized tuberculosis. Cheesy lymph glands may 

 communicate with the interior of the large intestine (Lothes). 

 In some cases the intestinal mucous membrane contains numer- 

 ous nodules of the size of a hazelnut, some of them ulcerated 

 on the crest, also irregular ulcers with smooth or ragged 

 borders, ranging in size up to that of the palm of a hand ; their 

 base may extend to the submucosa and contain small tubercles., 

 The large intestines and the rectum alone may be thus affected 

 (Eatz; Darmagnac observed a case of perforation of a rectal 

 ulcer producing acute peritonitis). The liver may contain 

 similar lesions but they are rare in the spleen. The former 

 may reach three times its normal size and the latter has been 

 observed to weigh 13 kg. (Schulz) or, according to A. Marcus, 

 dimensions of 74 by 581/2 cm. (According to MacFadyean, 

 Johne and Kitt tumors of this sort formerly described as 

 lymphadenomata, which occasionally are almost tendinous in 

 consistency are usually tuberculous in nature.) 



The disease of the lungs is usually miliary in nature. Less 

 frequent are tumors as large as a nut or larger, which section 

 appear homogeneous, like a turnip, or with soft centers con- 

 taining a dirty gray or yellow purulent or caseo-purulent mass ; 

 in some cases they are enclosed in a connective tissue capsule. 

 The intervening connective tissue is either normal or exces- 

 sively proliferated. Changes indicating acute inflammation, as 

 are observed in glanders, do not occur in tuberculosis. The 

 peribronchial lymph glands are usually considerably enlarged 

 and contain yellowish tubercles. The mucous membranes of 

 the respiratory tract may also show ulcers. 



Tuberculosis of the serous membranes (peritoneum, pleura 

 and pericardium) usually occurs in the form of typical pearl 

 disease (Bang, Nocard, Felisch, Foelger, Eatz). Occasionally 

 there is an accumulation of much sero-fibrinous exudate in the 

 pleural cavity and the pericardium (Aubry). Tuberculous 

 lesions may occur also ; in the pharyngeal and cervical glands 

 (Froehner), in the vertebrae and ribs (Wolff, Haendel, Town 

 & Hobday), in the heart-muscle (Foelger), in the subcutaneous 

 connective tissue and in the muscles (Cadiot, Fally). Enders 

 described the rare occurrence of complete calcification of the 

 thoracic aorta where it lies adjacent to the dorsal vertebrae. 

 Hansenkamp describes tuberculous lesions in the marrow of 

 the lumbar vertebrae and in the adjacent membranes. Behr 

 Vol. 1-35 



