ANTHRAX IN ANIMALS 341 



vulsive movements ; and progressive weakness, with cyanosis, 

 is followed by death in from twelve to forty-eight hours. In 

 the more prolonged cases widespread oedema and extensive 

 enlargement of lymphatic glands are marked features ; and in 

 the glands, especially about the neck, actual necrosis with 

 ulceration may occur, constituting the so-called anthrax car- 

 buncles. Such subacute conditions are especially found among 

 horses, which are by nature not so susceptible to the disease as 

 cattle and sheep. Occasionally even in susceptible animals 

 recovery takes place. 



On post-mortem examination of an ox dead of anthrax, the 

 most noticeable feature — one which has given the name "splenic 

 fever " to the disease — is the enlargement of the spleen, which 

 may be two or three times its natural size. It is of dark-red 

 colour, and on section the pulp is very soft and friable, sometimes 

 almost diffluent. A film made from the spleen and stained with 

 watery methylene-blue will be found to contain enormous 

 numbers of bacilli mixed with red corpuscles and leucocytes, 

 chiefly lymphocytes and the large mononucleated variety (Fig. 

 102). Paraffin sections stained by Gram's method show that 

 the structure of the pulp is considerably disintegrated, whilst the 

 bacilli swarm throughout the organ, lying irregularly amongst 

 the cellular elements. The liver is enlarged and congested, and 

 may be in a state of acute cloudy swelling. The bacilli are 

 present in the capillaries throughout the organ, but are not so 

 numerous as in the spleen. The kidney is in a similar condition, 

 and here the bacilli are chiefly found in the capillaries of the 

 glomeruli, which often appear as if injected with them. The 

 lungs are congested and may show catarrh, whilst bacilli are 

 present in large numbers throughout the capillaries, and may 

 also be found in the air cells, probably as the result of rupture 

 of the capillaries. The blood throughout the body is usually 

 fluid and of dark colour. 



The lymphatic system generally is much affected. The 

 glands, especially the mediastinal, mesenteric, and cervical 

 glands, are enlarged and surrounded by cedematous tissue, the 

 lymphatic vessels are swollen, and both glands and vessels may 

 contain numberless bacilli. The heart-muscle may be in a state 

 of cloudy swelling, and the blood in its cavities contains bacilli, 

 though in smaller numbers than that in the capillaries. The 

 intestines are enormously congested, the epithelium more or less 

 desquamated, and the lumen filled with a bloody fluid. From 

 all the organs the bacilli can be easily isolated by stroke, cultures 

 on agar, 



