74 ROBEKT GRAHAM AND HERMAN R. SCHWARZE 



sumed ten to twenty lethal equine doses of botulinus toxin 

 (type B) at one time in wholesome feed without inducing notice- 

 able symptoms. In fact our observations indicate that a mature 

 ruminant may possess marked resistance to botulinus toxin 

 (type B) in the feed. 



Information relative to B. botulinus-\ike organisms and their 

 relation to forage poisoning in cattle, if any, has been eagerly 

 sought in natural outbreaks, yet the degree of tolerance experi- 

 mentally observed in mature, healthy experimental cattle to 

 botulinus toxin (type B) suggested the possibility of an inde- 

 pendent factor in this disease of bovines, and until recently the 

 spontaneous occurrence of forage poisoning in cattle, wherein 

 the rations proved to be contaminated with B. botulinus-like 

 organisms, was in our observations without convincing bacterio- 

 logical and immunological evidence, 



SILAGE CONTAMINATED WITH B. BOTULINUS 



In January, 1920, a sample of silage (Laboratory index 126), 

 was received from Mr. L. W. Wise of Iroquois County, Illinois. 

 It was stated that the sample in question was representative of 

 feed which had apparently proven injurious to a herd of forty- 

 seven pure bred cattle of all ages. Upon physical examination 

 the silage did not show noticeable indications of spoilage. There 

 were scant circumscribed colonies of wild yeast (Monilia Can- 

 dida Bon) on some of the leaves, which was identified in pure 

 cultures by Professor H. W. Anderson, Assistant Professor of 

 Pomology, University of Illinois. The colonies of yeast were 

 visible only on close examination and the specimen could not be 

 regarded as mouldy in the general sense that some feeds harbor 

 organisms of this class. Indefinite evidence which pointed to 

 the disease producing properties of the silage consisted of symp- 

 toms of illness observed in several (18) cattle, and as described 

 by the owner, included inappetance, marked emaciation, con- 

 stipation and general unthrift, with some transitory nervous 

 manifestations (see fig. 1). Four animals chronically affected 

 died. The younger animals of the herd were apparently not as 

 susceptible as the mature full grown animals, or it may be pre- 



