Studies in Forage Poisoning VI. 121 



to eat the oat hay and ear corn, respectively, for a period of 30 

 days, at the end of which time they were released. No manifest 

 symptoms were observed in these two animals. The prelimi- 

 nary feeding test, as described above, indicated that the etio- 

 logic factor of the disease, as observed in this outbreak, was pos- 

 sibly contained in the ensilage, further supported by the fact 

 that the oat hay and ear corn being fed at the time the outbreak 

 occurred were released after the feeding test and fed with ap- 

 parent safety to the remaining mule stock. 



The Relation of Botulism Antitoxin to the Etiologic 

 Factor in the Ensilage. 



In previous studies an oat hay 4 from a remote outbreak 

 was proved to incorporate the etiologic factor of forage poison- 

 ing, by feeding tests with horses, and was later found to be 

 contaminated with an organism resembling B. botulinus. In 

 conducting further studies upon the ensilage in question, an 

 effort was made to determine the relation of botulism antitoxin 

 to the etiologic factor contained in the ensilage. Apparently 

 healthy horses, Nos. 4, 5 and 6, were placed in a stable adjoin- 

 ing the silo. All three animals were to be given daily rations 

 of the ensilage exclusively; horses Nos. 4 and 5 were given sub- 

 cutaneous injections of serum from a goat immune to B. botu- 

 linus on February 13th, 1917. The control, No. 6, received no 

 treatment. The injection in horse No. 4 was followed by a 

 marked reaction (syncope) and the animal was in a moribund 

 condition in twenty-four hours. The cause of death is not ex- 

 plained unless it falls within the category of anaphylactic phe- 

 nomena. It is to be noted that this animal received no silage-.. 



Horses No. 5 and No. 6 appeared normal on February 

 14th, and received direct from the silo daily maintenance ra- 

 tions of the ensilage. Horse No. 5 received weekly subcutaneous 

 injections of botulism antitoxin. On the 24th of February the 

 control horse, No. 6, appeared depressed, with drawn flank. 

 The following day the animal was permanently decumbent, 

 presenting clinical manifestations similar to those observed in 



Bulletin No. 207, Ky. Exp. Sta., 1917. 



