HEALTH AND DISEASE OF POULTRY 601 



windows should be opened (if possible from the outside in order to 

 avoid entering the room and inhaling the pungent, irritating fumes 

 of formaldehyde gas) and the room well aired for several hours. 



It may sometimes become necessary to disinfect a single in- 

 cubator or brooder. The following suggestions are offered for 

 those who desire to use at such times the permanganate-diluted 

 formalin method. Keeping in mind the impossibility of making 

 these machines absolutely air tight, the following procedure and 

 adaption of the ratio mentioned above in the disinfection of an 

 ordinary 240-egg incubator is recommended. Start the lamp, so 

 that the incubator shall be thoroughly warmed. Cover the slat 

 bottom of the incubator with a few layers of newspaper, tacking 

 or pasting (preferably the latter) the four sides. Plug all cracks 

 and openings except the door space. Whenever possible, soiled 

 diaphragms should be replaced with new felt or burlap, as the case 

 may be. If it is not feasible to do this, wash off all dirt and tilt the 

 diaphragms inside the incubator so that they may not interfere 

 with the free progress of the gas. Put out the lamp. Place in 

 the center of the newspaper-covered floor of the incubator a saucer 

 containing 1 leveled teaspoonful of crystals of permanganate of 

 potash. Mix 2 teaspoonfuls of formalin (38 to 40 per cent formal- 

 dehyde) with 2 teaspoonfuls of water and pour upon the perman- 

 ganate of potash. Quickly close the incubator door, making the 

 cracks as tight as possible by means of wet newspaper. After four 

 or five hours open and air the incubator for a few hours. The pun- 

 gent, irritating formaldehyde-laden atmosphere that sometimes 

 lurks about the incubator after this treatment may be neutralized 

 by placing in the incubator a saucer containing a very small quan- 

 tity of weak ammonia water. 



Clean Breeding. This is accomplished by breeding from the 

 youngest females consistent with good breeding. 



REASONS FOR APPLYING THE MAXIMS. 



The reasons connected with the application of each of the 

 maxims are as follows: 



Clean Out With Epsom Salt. For the same reason that a 

 chicken uses the dust bath, it is given the Epsom salt, namely, to 

 get rid of or to diminish tne number of parasites. The dust bath 

 assists in removing the ectoparasites (outside parasites). The Epsom 

 salt cleans out the endoparasites (inside parasites). Some of these 

 may be large enough to be seen with the unaided eye, as, for 

 instance, the various intestinal worms, whereas others may be min- 

 ute enough to require high powers of the microscope for detection, 

 or even be so infinitesimal as to belong to the class of ultramicro- 

 scopic germs. 



It is customary to regard the presence of intestinal worms as a 

 more or less normal condition and not deserving of any anxiety. 

 But it may well be pointed out that the intestinal parasites of 

 chickens, be they worms, molds, bacteria, or protozoa, are certainly 

 not beneficial to the chicken. On the other hand, any one of 

 them, no matter how apparently harmless, may produce disease 



