NATURAL AND ARTIFICIAL INCUBATION 



89 



Figure 89. — Fertile egg at the end of 14 

 days incubation, showing the develop- 

 ment of the embryo. 



pleted, remove the egg tray 

 and open the ventilators ac- 

 cording to the directions fur- 

 nished with the machine and 

 retain the chicks in the in- 

 cubator from 24 to 36 hours 

 after the hatch is over before 

 removing them to the brood- 

 ers. Chicks that pip the 

 shell but are unable to get out 

 through their own efforts 

 rarely amount to much if 

 helped out. 



Disinfecting and storing 

 the incubators. When the hatching season is over, clean 

 and disinfect the incubators. Empty and clean the lamps 

 and store these parts in the machine. The incubator may 

 be disinfected once a year or oftener, especially if any 

 disease is present in the flock. Some poultrymen disinfect 

 their machines before and after each hatch, as a preventive 

 measure against disease. A ten per cent solution of a 

 reliable coal-tar disinfectant and water may be used to 



wash out the machine and 

 to disinfect the egg trays 

 and nursery drawer. A 5 

 per cent solution of crude 

 carbolic acid and water 

 will also be found effective 

 for disinfecting the incu- 

 bator. If the burlap on 

 the bottom of the incuba- 

 tor becomes dirty, it is ad- 

 Pigure 90.— An infertile egg at the end visable to rencw it rather 



of 14 days. Such an egg appears some- tU„„ f„ nloan if 

 what clear before the egg tester tud,u uo ciedU 10. 



