DISEASES, &o. 187 



336. Chilled Brood.— " Chilled Brood" is the name given to 

 the condition of larvae which have died through lack of the heat 

 necessary to their life and development. It is frequently found 

 after any sudden decrease of temperature out of doorSj and in 

 the apiaries of careless, or ill-informed bee-keepers. 



337. Symfious. — Chilled brood is sometimes mistaken for 

 foul brood (349), but, examination of the contents of affected 

 cells will show the larvae, in the case of chilled brood, grey in 

 the initial stages, and subsequently black, whereas brown is 

 the colour assumed by foul brood (350). 



338. Cause. — Chilled brood may be caused in spring, when 

 the brood nest has been extended, by a sudden return of cold 

 weather forcing the bees to cluster in the centre of the brood 

 nest, and to leave the outer patches of brood uncovered : it may 

 result from premature or excessive " spreading of the brood " 

 (193): or from undue exposure of the brood combs during 

 manipulations. (185b). 



339. Prevention. — To avoid the danger of chilled brood, 

 hives should be kept warm during spring and late autumn 

 breeding : spreading the brood should be practised with much 

 discretion, full account being taken of the prevailing weather 

 and of the risk of a sudden drop in the temperature at night : 

 manipulations of the brood nest on cold days should be 

 avoided as much as possible : and, at no time should combs 

 containing brood be exposed to chill winds. 



340. Treatment. — When time permits, the chilled brood may 

 be picked out of the cells with a pin, and be buried. Failing 

 this, and where a large number of stocks have to be dealt with, 

 the cappings of cells containing chilled brood may be broken, 

 when, the bees will carry out the dead. 



341. Black Brool. — In America, this disease is now identified with 

 "European Foul Brood," which is the name there given to tlie 

 disease investigated by Cheshire (351) and attributed by him to 

 Bacillus alvei. It is now ascribed to the germ Bacillus pluton. It 

 is highly infectious in larvffi, but not in adult bees (359b), 



342. Symptoms. — The brood is usually attacked in the early 

 larval stages, and death generally occurs before the cells have 

 been sealed. A yellow, pin-head spot on the larva, is the first 

 sign, and death resulting, the larva becomes brown in colour, 

 and finally almost black. But, whereas the rotten masses in 

 foul brood become sticky, and ropy, in black brood they ttirn 

 into a granular, liquid condition, not adhering to the cell-waUs, 

 and having a sour smell quite unlike that given off by loul 

 brood. 



