76 ROBERT GRAHAM AND HERMAN R. SCHWARZE 



sumed that the older animals consumed more of the silage. 

 The owner noted that trough space prevented the small animals 

 from getting as liberal a portion of the feed as the older animals 

 secured. Simultaneously with the marked illness and death of 

 the animals, feeding of silage was discontinued and the herd 

 improved. After an interval of three weeks the cattle were 

 again allowed to eat of the silage in small quantities and illness 

 again appeared in some animals of the herd. The symptoms 

 were analagous to the manifestations noted in the original out- 

 break, but the silage was promptly eliminated from the daily 

 ration and the affected animals improved and made a complete 

 recovery. This experience suggested to the owner that the 

 silage could not be safely used for feeding purposes, and oppor- 

 tunity to observe the effect of the continuous feeding of the silage 

 in this herd or to other cattle or horses was not provided. 



The clinical illness in these cattle on two separate occasions 

 was at marked variance with experiments in feeding rations 

 spontaneously contaminated with botulinus toxin to horses and 

 mules, in that the character of the disease in cattle was chronic 

 and slowly fatal. Furthermore, the manifest symptoms reported 

 in this herd had not been noted in feeding B. botulinus contami- 

 nated silage to cattle, yet the anamnesis appeared somewhat in 

 keeping with other spontaneous outbreaks of a disease of unknown 

 etiology occurring in cattle throughout the corn belt states. 



While clinical deductions might have suggested the presence 

 of a poisonous substance in the silage, there appeared two impor- 

 tant possibilities for consideration in this assumption, (a) 

 The poisonous substance in the silage was not overcome by the 

 natural resistance of the animals, or (b) the illness was induced 

 by bacterial agents, chemicals, et cetera, unassociated with the 

 silage and not mentioned b}^ the owner. No feeding experi- 

 ments were conducted to incriminate the silage further, but a 

 bacteriologic examination of this feed was made. 



BACTERIOLOGICAL FINDINGS 



A sample of silage (50 grams) received for examination w^as 

 immersed in sterile water and allowed to macerate in a dark 

 place twenty-four hours at a temperature of 22 °C. The sample 



