BROODING 



439 



a hover, which is supplied heat by means of a heating appa- 

 ratus, with either hot air or hot water. The hover should be 



"*■!«)* 



Fig. 164. — The mother and her brood. (Iowa Experiment Station.) 



provided with a thermoregulator. It is essential to provide 

 sufficient ventilation to allow fresh air, so the chicks have the 



Fig. 165. — A colony brooder house. The hover is in the center of the house. 



proper amount of oxygen and to allow the escape of polluted 

 air containing carbon dioxid given off from the body of the 



