40 MISCELLANEOUS PAPEKS ON APICULTURE. 



Just how the bacteria are carried from a dead larva to a healthy 

 one we do not know. It is not uncommon, in examining the brood, to 

 find only a portion of a larva in a cell, the bees having removed a 

 part of it. When the body wall of a larva is broken in examining 

 for foul brood, bees readily suck up the contents which flow out. 

 This is true when the larva which is punctured is healthy, or when 

 it is sick with disease, or after it has been dead a few days. The 

 larva? at these stages of the disease contain a very large number of 

 the disease-producing bacteria. These observations would indicate 

 that in this way, in part at least, the infectious material might be 

 carried to healthy larvae. Actual contact of the appendages of the 

 bee with the foul-brood material, and the subsequent contact of the 

 same appendages with the food of the larva?, may be a method by 

 which the disease-producing bacteria are spread. We do know that 

 in foul brood it is possible to obtain Bacillus larvce from the honey, 

 and we do know that when bees are fed the spores of Bacillus larvce 

 in honey American foul brood will appear in the apiary. 



The spores of this bacillus are very resistant to heat and other 

 disinfectants. They resist the boiling temperature of water for 

 fifteen minutes. In 5 per cent carbolic acid the} 7 were not killed in 

 two months' time. This was demonstrated by obtaining growth in 

 cultures after the spores had remained in this disinfectant for that 

 length of time. Likewise it has been demonstrated that the spores 

 of Bacillus larvce, when taken from the scales of American foul brood, 

 resist the action of mercuric chloride (corrosive sublimate), 1:1,000 

 aqueous solution, for two months. Having such facts before us, we 

 can better judge the methods for treatment. 



In treating this disease we must bear in mind the preventive and 

 curative measures. In the preventive treatment many of the condi- 

 tions you can control; others may be difficult. You can at least be 

 sure that you import no bees or used supplies which might have been 

 in an infected apiary. Use no old combs and feed no honey of 

 which you do not know the history. In this way the bacillus which 

 causes the disease in a large measure can be kept out of the apiary. 

 There are conditions which are difficult to control. Should a near-by 

 apiary be diseased and some of the colonies become weak or die out, 

 it might be difficult for you, in a dearth of nectar, to keep your bees 

 from robbing the diseased apiary and in this way bringing these 

 disease-producing germs to your health} 7 colonies. 



Some preliminary experiments have been made, but the results do 

 not indicate that drugs, in the treatment of this disease, have the 

 value advocated by some English writers. 



