122 Bulletin No. 208. 



the animals originally afflicted on this farm. On February 26th, 

 1917, the animal was moribund and was destroyed. Autopsy 

 was not conducted. The serum-treated animal, No. 5, continued 

 to receive the ensilage each day, exclusive of other feed, for a 

 period of 30 days and remained apparently healthy. The re- 

 maining ensilage was then fed daily to cattle, without notice- 

 able effect, thus concurring to a degree, in this instance, with 

 the general observation that cattle are less susceptible to so- 

 called ensilage poisoning than horses and mules. 



An Anaerobic Organism from the Ensilage. 



An anaerobic, spore-forming organism isolated from the 

 oat hay previously referred to proved pathogenic for guinea 

 pigs and horses. 2 cc. of the broth culture of the organism in 

 question, disguised in wholesome oats, proved capable of en- 

 gendering clinical manifestations and anatomic alterations in 

 horses and mules similar to those recognized in afflicted ani- 

 mals as the result of feeding the original oat hay or water in 

 which the oat hay was immersed. 



Representative samples of the corn, the oat hay and the 

 ensilage being fed on the Gaines farm at the time the outbreak 

 occurred in December, 1916, were sent to the Experiment Sta- 

 tion for examination. These samples were kept in Mason fruit 

 jars at 42 F. until the conclusion of the preliminary feeding 

 tests. From the sample of ensilage in question, an anaerobic, 

 sporulating, Gram-positive, rod-shaped organism, 0.8 micron to 

 1 micron wide and 2y 2 microns to 6 microns long was isolated 

 which resembled B. botulinus morphologically and culturally as 

 propagated in alkaline pork broth (Figs. 1 and 2). Broth cul- 

 tures of this anaerobe proved fatal to guinea pigs (250 to 300 

 grams), introduced by the mouth in amounts of 0.02 cc., in 45 to 

 50 hours. 0.01 cc. broth culture by the mouth resulted fatally to 

 a 250 gm. guinea pig in 5 days. The filtered broth culture 

 administered by the mouth proved fatal to guinea pig,s 2 horses 

 and a mule. Horse No. 120 was given 2 cc. of the filtrate dis- 

 guised in 1000 gms. of wholesome oats at 9 a. m., May 31st, 1917, 

 and succumbed in 22 hours, without premonitory symptoms 



