58 POULTRY DISEASES 



the disinfectant used must be applied to them as carefully 

 as to other parts of the building. 



The floor and roosts should next be scraped, and they and 

 the walls and ceiling carefully and vigorously s\vei)t. All 

 parts of the interior of the building must then be thoroughly 

 scrubbed with water, to which lye has been added, and a 

 broom or stiff brush and then Hushed out, using plenty ot 

 water. The building is then, and not till then, ready for 

 the use of the disinfectant. 



There are three different classes of agents that may be 

 successfully used in disinfection. The disinfectant may be 

 applied (1) in gaseous form, (2) as a liquid, or (3) heat 

 may be utilized. 



A gas may be used in disinfecting only when the building 

 can be closed tightly enough to prevent its ready escape. 

 This excludes the great majority of poultry houses; but in 

 such as it can be employed, all doors, windows and other 

 openings nuist be tightly closed and sealed for several hours. 

 After disinfecting a building with gas the interior should be 

 sprayed, as directed under the use of liquid disinfectants. 



Of the gases that may be used, only three need to be con- 

 sidered here — hydrocyanic acid, formaldehyd and sulphur 

 dioxid. 



Hydrocyanic acid gas is extremely poisonous, a single 

 breath of it sometimes sufficing to kill a man. It possesses 

 the advantage of requiring but a few minutes to effectively 

 disinfect a building and of killing all living organisms in 

 it, bacteria, molds, parasites and even roaches and other ver- 

 min, and rodents. It will also destroy the eggs of parasites. 

 It is extremely dangerous, however, except ni professional 

 hands and its use nuist not be attempted by the poultry man. 



Excluding hydrocyanic acid on account of the hazard at- 

 tending its use, formaldehyd is the gaseous disinfectant of 

 choice. It may be procured in a forty per cent watery solu- 

 tion known as formalin, from which the gas may be readily 

 generated. 



After hermetically sealing all openings into the ])uilding 

 except one door, place in an earthen or metal vessel two 

 quarts of formalin for each 1. 000 cubic feet of space in the 

 l)uilding, place this vessel in a much larger one and set on 

 the floor, then empty into the formalin one-half pound of 

 potassium permanganate for each f|uart of formalin and re- 

 treat from the building at once and close the door. 



The temperatui'c of the room, during the disinfection, 

 should be above ."iO degrees Fahreidieit, and the more it is 



