PRAIRIE FARMER'S POULTRY BOOK 



9. Do not cool the eggs until after the seventh day. Watch 

 the hen. She sits close during the first week, hardly leaving 

 the nest for food. Beginning with the eighth day, cool the 

 eggs once a day up to the 18th day. Many chicks are ruined 

 by too much cooling. If we are so careful that the tender, 

 baby chick shall not become chilled, why should we not con- 

 sider the tender embryo in the shell? Cool the eggs grad- 

 ually. When they feel slightly cool when applied to the eye- 

 lids, then is the time to return the trays to the incubator. 

 Keep the incubator closed while the eggs are cooling. 



10. Keep the bulb of the thermometer on a level with the 

 top of the eggs, but it should not touch any egg. It will then 

 register the temperature of the air in the brood chamber. 

 Every thermometer should be tested for accuracy. 



11. Keep the room temperature at 60 degrees. You cannot 

 maintain the proper temperature in the incubator if the room 

 temperature goes below 50 degrees or above 70 degrees. 



12. Provide an abundance of pure air. A crowded, ill- 

 ventilated living room is not the best place for an incubator. 



Why do Chicks Die in the Shell? 



Many chicks die in the shell because the germ is weak. 

 They develop until the hatching period and then have not the 

 vital energy to get out of the shell. Many are infected with 

 disease germs to which they succumb before they are able to 

 pip the shell. Some are drowned because of too much moist- 

 ure. The air cell should be watched to make sure that the 

 eggs are properly dried out at hatching time. Some die for 

 want of moisture. The membrane surrounding the chick be- 

 comes dried to the outer membrane, and the chick is unable 

 to turn in the shell. Some die because overheated. The al- 

 bumen of their blood becomes coagulated by the excessive 

 heat and death ensues. Some become chilled, which means a 

 loss of vitality. Some perish on account of rough handling. 

 The vitelline membrane becomes ruptured or the shell be- 

 comes cracked, and in either event death ensues. 



What is the Cause of Cripples? 



A very common cause is excessive heat in the incubator. 

 It is a very rare thing for a hen to hatch a cripple. She does 

 not permit the temperature to rise above 107 degrees. Cripples 



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