14 Anthrax. 



very marked and confined to smaller areas, particularly those 

 corresponding to the Peyer 's patches and solitary follicles, thus 

 causing the mucous membrane to project into the lumen of the 

 intestine in the form of spherical protuberances (carbuncles), 

 or as elongated, thick pads. On the protuberances or pads the 

 mucous membrane appears necrotic, which sometimes affects 

 only the superficial layers, although its entire thickness may be 

 involved, giving it the appearance of a pale yellow pulpy de- 

 posit. The inner surface of the abdominal wall may also show 

 various sized ulcers with greatly swollen blackish-red borders, 

 their bases being covered with necrotic tissue shreds. Around 

 the nodules and ulcers the mucous membrane and subserous 

 connective tissue usually manifests a marked gelatinous infiltra- 

 tion and permeation with hemorrhages. 



The lungs are highly congested, and edematously infiltrated. 

 The respiratory mucous membrane is hyperemic, catarrhal and 

 swollen, particularly at the opening of the larynx, and contains 

 numerous ecchymoses. The brain and meninges are also 

 hyperemic, and between the latter sometimes extensive flat 

 blood coagula are present (apoplexia intermeningialis). 

 Hemorrhages may also occur exceptionally in the brain sub- 

 stance. The body cavities of the carcass frequently, especially 

 in warm weather, contain a reddish fluid. The internal lymph 

 glands show a condition similar to that seen in the external 

 glands except that the condition is more marked, particularly 

 in the mesenteric glands. 



The blood is dark to blackish-red in color, contains only 

 a few loose fibrin coagula, and clears up only slowly in the air. 

 On microscopic examination the leucocytes appear greatly in- 

 creased (hyperleucocytosis). 



Anthrax bacilli are usually present in great numbers in 

 the blood, spleen, lymph glands and parenchymatous organs. 

 Occasionally, however, but few are present, especially in the 

 rapid, apoplectic form of the disease. 



The pathological changes described are the more distinctly developed, the 

 more slowly the disease had progressed. Their distribution depends in the first 

 place upon the nature of the infection as the edema and hemorrhages are most 

 pronounced at the point of infection. However, superficial edemas may also develop 

 after infections through the intestines, whereas the described intensive changes in 

 the intestinal mucous membrane develop almost exclusively in this mode of infec- 

 tion, although they are not invariably present in such a conspicuous form in all 

 cases. 



The manifestations of the changes in hogs differ inasmuch 

 as in most cases the lesions are principally confined to the 

 pharyngeal region. In addition to a marked gelatinous-hemor- 

 rhagic infiltration of the pharyngeal connective tissue and the 

 retropharyngeal lymph glands, the tonsils are covered by 

 strongly adherent pale-yellow, pseudomembranes, and are sur- 

 rounded by the greatly swollen mucous membrane. The tissue 

 of the tonsils under the pseudomembranes appears yellowish- 

 gray, lusterless and several millimeters in thickness. The in- 



