Abstract
Two substances, toxic for rabbits, were produced in cultures of a strain of Friedlander's bacillus, originally isolated from an epidemic of pneumonia among guinea pigs.
The organism is highly pathogenic for guinea pigs and rabbits by any route of injection. Mice are also readily infected by intraperitoneal injection; a dilution of 1:10 billion of a 24-hour old broth culture (5-20 bacteria) produces the characteristic sticky mucoid exudate. Culturally, the organism forms acid but no gas in glucose, lactose, saccharose, maltose, mannite, and salicin, but not dulcite. It also reduces nitrates to nitrites, and gives a negative methyl red and Voges-Proskauer reaction.
Toxic Substance A. Procedure: The organism was grown in Huntoon's hormone broth containing 2 per cent peptone, in shallow layers in pint bottles, 20 cc. to a bottle giving a depth of 3/8 inch. The bottles were shaken once a day. The cultures were finally filtered through Berkefeld (N) candles. The pH and M.L.D. of the toxin for rabbits were determined at regular intervals.
As shown in Clzart 1, the toxicity of the broth filtrate begins to rise after the growth curve has exhibited a tendency to descend, and after the pH has risen above 7.0. In several experiments, the peak of the toxin curve was reached when the pH was between 8.0 and 8.6, then the toxicity remained constant for several days.
Rabbits inoculated intravenously appeared sick within 2 to 6 hours. The animals were weak and depressed; the breathing was labored and rapid, and there was profuse watering of the eyes. The dyspnea increased until the respiration showed marked wheezing and evidence of much moisture in the lungs and trachea. As a rule the animals died in from5 to 24 hours.
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