AMERICAN FOULBROOD. 



31 



RESISTANCE OF AMERICAN FOULBROOD SPORES TO FERMENTATION 



A few preliminary experiments relative to the effect of fermenta- 

 tive processes on the spores of American foulbrood were made. The 

 processes involved concern chiefly the sugar splitting and the proteo- 

 lytic enzymes. In experiments relative to the former, the scale 

 material was suspended in a 20 per cent aqueous solution of honey 

 and, in those relative to the latter, it was suspended in a 1 per cent 

 aqueous solution of peptone. In each case a small bit of soil was 

 added to inoculate the suspending solution still further. These 

 suspensions, respectively, were distributed in test tubes and allowed 

 to undergo fermentation. Observations were made at incubator and 

 outdoor temperatures. The outdoor temperature was that which 

 obtained in an empty hive body covered, and standing in the apiary 

 at the time of the year shown by the dates of the experiments. After 

 intervals reckoned in days colonies free from disease were inoculated, 

 each with a suspension from a single tube. The experiments are 

 summarized in Table X: 



Table X. — Resistance of the spores of Bacillus larvae to fermentation 



Date of 

 experi- 

 ment. 



Nature of the 

 suspension. 



Period. 



Temperature. 



Results of inoculations. 



1916. 

 Aug. 14.. 



Honey 



Days. 

 26 

 53 

 24 

 53 

 26 

 53 

 24 

 53 



Outdoors 



American foulbrood produced. 

 Do. 



Sept. 9... 

 Aug. 11.. 

 Sept. 9.. 

 Aug. 14.. 

 Sept. 9.. 

 Aug. 11.. 

 Sept. ... 



do 



do 



do 



Incubator 



Do. 



do 



do 



Do. 



Peptone 



do 



Outdoors 



Do. 



do 



Do. 



do 



Incubator.. . 



Do- 



do 



do 



Do. 









From Table X it will be seen that in the presence of fermentative 

 processes in the honey solution and in the peptone solution the spores 

 were alive and virulent after 53 days at incubator and at outdoor 

 temperatures. It is quite probable that they would have remained 

 so for a very much longer period. 



RESISTANCE OF AMERICAN FOULBROOD SPORES TO CHEMICAL 

 DISINFECTANTS 



While a mass of data was obtained relative to the effect of chemical 

 agents on the spores of American foulbrood, the results are still 

 considered as being preliminary in nature. In conducting the 

 experiments a suspension of disease material in an aqueous solution of 

 the disinfectant was used. This was drawn into capsules x (fig. 9) 



1 The ampules used are made from glass tubing of small bore by heating and drawing it into three bulbs. 

 The two intermediate constricted portions are wrapped with cotton. After being sterilized the ampules 

 are filled with the spore-containing suspension sealed and placed at different temperatures. Incubator, 

 room , and outdoor temperatures were employed. At the time of making the cultures the ampule is broken 

 at the two intermediate constrictions and the spore-containing suspension used in making the inocu- 

 lations is obtained from the intermediate bulb. By this method an immersion of the spores in the solution 

 for the entire period is assured. 



