BACILLUS OF GASTROMYCOSIS OVIS 265 



from the intestines and may be carried to a contused place which 

 furnishes a favorable location for multiplication. Kitt has reported 

 cases in which it appears that sheep may contract a malignant edema 

 of the lungs by inhalation. 



In natural infection the bacilli are found in the serous or watery 

 exudates. They occur in enormous numbers in the connective tissue 

 of the affected part, in more moderate numbers in the superficial 

 portions of the muscles and very scantily in its deeper substance. 



Artificial Inoculation. Equines, guinea-pigs, rabbits, rodents, cattle, 

 chickens, and pigeons are susceptible to artificial inoculation; dogs 

 and cats only very slightly. 



Protective Inoculation. Leclainche and Valee have shown that 

 animals may be protected against malignant edema infection by 

 inoculation of spore-containing material which has been heated for 

 seven hours at 92 C. Animals repeatedly treated with such vaccines 

 also develop an immune serum which will produce passive immunity 

 in other animals. All these tests are still in an experimental stage, and 

 neither protective virus inoculation nor passive immunization has 

 ever been used in practice. 



BACILLUS OF GASTROMYCOSIS OVIS. 



Occurrence. In the northern parts of Europe, Iceland, Norway, 

 the Faroe Islands, Scotland, Denmark, and also in North Germany, 

 a disease of sheep occurs which is known as bradsot, braasod, brada- 

 pestina, bradasottina, bradafarid, braxy, or technically, as gastro- 

 mycosis ovis. The disease runs a very rapid course. A sheep appar- 

 ently well in the evening may be dead the following morning. The 

 disease was described as early as about the middle of the eighteenth 

 century. The first bacteriologic examinations were made by Kingberg, 

 and the first description of the bacillus of bradsot was published by 

 Nielsen, whose findings were confirmed and extended by Jensen. 



Pathologic Changes. Jensen describes these as follows : The mucosa 

 of the stomach and small intestine exhibits a serous hemorrhagic 

 infiltration, likewise the abdominal connective tissue, which may also 

 show infiltration with gas. The mucosa of the "lab" stomach (rennet) 

 is sometimes necrotic, and upon microscopic examination the tissues 

 here show enormous numbers of bradsot bacilli. When the disease 

 is produced by the experimental subcutaneous inoculation the 

 animals develop hemorrhagic infiltrations of the deeper muscles, 

 often with gas infiltration, and the pathological picture very much 

 resembles symptomatic anthrax. Jensen failed to produce bradsot 

 in sheep by feeding them with hard material, including thistles 

 which had been contaminated with cultures of the bacilli. 



Morphology. The bacillus of gastromycosis ovis is a large rod, 2 

 to 6 micra long, 1 micron wide. It has rounded ends, and is found 



