530 BUREAU OF ANIMAL INDUSTRY. 



summer, the virus ma}' be inhaled and be absorbed from the lining of 

 the lungs. If contained in harness leather, it needs but an abrasion 

 of the skin, as the harness rubs it, to transfer the spore from the 

 leather to the circulation of the animal. 



The wi"iter saw a case of anthrax occur in a groom from thg use of a 

 new horse-brush. The strap which passes over the back of the hand 

 inoculated an abrasion on the knuckle of the first fingei", and in twelve 

 hours a "pustule" had formed and the arm had become infected. 



Symptoms. — The S3^mptoms of anthrax usuall}" develop with extreme 

 rapidity. The horse is dejected and falls into a state of profound 

 stupor, attended by great muscular weakness. The feeble, indolent 

 animal, if forced to move, drags its legs. There are severe chills, 

 agitation of the muscles, sjanptoms of vertigo, and at times colicky 

 pains. The mucous membranes turn a deep ocher or bluish red color. 

 The body temperature is rapidly elevated to 104'^ or lOo'^ F. The 

 breathing is increased to thirty or fort}' respirations in the minute 

 and the pulse is greatly accelerated, but while the arteries arc soft and 

 almost imperceptible, the heart beats can be felt and heard, violent and 

 tumultuous. In some cases, when inoculation is through the skin, 

 large subcutaneous swellings appear; these may involve a leg, a shoul- 

 der, one side of the body, or the neck or head. The swelling is at 

 first hot and painful, but afterwards it becomes necrotic and sensation 

 is lost. The symptoms last but two, three, or four days at most, when 

 the case usually terminates fatally. An examination of the blood 

 shows a dark fluid which will not clot, and which remains black after 

 exposure to the air. After death the bodies putrify rapidly and bloat 

 up; the tissues are filled with gases, and a bloody foam exudes from 

 the mouth, nostrils, and anus, and frequently the mucous membranes 

 of the rectum protrude from the latter. The haii-s detach from the 

 skin. Congestion of all the organs and tissues is found, with intersti- 

 tial hemorrhages. The muscles are frial)le and are covered with 

 ecchymotic spots. This is specially marked in the heart. 



The black, uncoagulated, and incoagulable blood shows an iridescent 

 scum on its surface, which is due to the fat of the animal dissolved by 

 the ammonia produced by the decomposed tissues. The serum oozes 

 out of every tissue and contains broken-down blood, which, when 

 examined microscopically, is found to have the red globules crenated 

 and the leucocytes granular. A ligh power of the microscope also 

 reveals the bacteria in the shape of little rod-like bodies of homoge- 

 neous texture with their brilliant spores. 



The lymphatic ganglia are increased four, five, six, or ten times their 

 natural size, enlarged by the engorgement of blood. The spleen shows 

 nodulated black spots containing a muddy blood, which is found teem- 

 ing with the virus. This organ is nmch enlarged and is quite friable. 

 The mucous membranes of the intestines are congested and reddish 



