98 INCUBATION 



the vitality of the germs or the egg be lacking, but the 

 latter obviously cannot be present without the former. 

 Chicks that are not strong and of abundant vitality 

 when hatched should never be raised for breeders, but 

 such fowls may be used for market poultry. 



There is a marked difference between the production 

 of fowls for exhibition or for beauty and the production 

 of those fitted for egg yielding and for table meat. 

 Where exhibition fowls are desired, the producing stock 

 must be yarded to avoid the mixing of breeds or 

 varieties. This is necessary only during the breeding 

 season. At other times the old and young stock may 

 have free range. Where egg producers and market poul- 

 try are desired, it is best to give the breeding stock all 

 possible liberty. It is best to keep only one variety, 

 and the flock should have free range if possible. 



The records of artificial incubation are derived from 

 experiments with different makes of incubators. 



The hatch from hens ranged as high as 83.3% and as 

 low as 50%, and that of the incubator from 77.1% to 

 32.5%. 



Selection of Eggs for Incubation. Eggs for hatching 

 in an incubator should all be of one kind, size, and 

 color; for only when eggs of such character are incu- 

 bated together can uniform hatching be secured. 



Eggs from Leghorns and Brahmas do not hatch -well 

 if both are together in the same incubator, for the eggs 

 of the Leghorns usually hatch during the twentieth day, 

 and the hatching of the Brahma eggs may be delayed 

 to the end of the twenty-first day. If eggs from Leg- 

 horns, Plymouth Rocks, Wyandottes, and Brahmas are 

 all together in the one incubator the hatch is irregular. 

 Eggs but 1 da. old hatch a day sooner than eggs that 

 are 2 wk. old. Leghorn eggs placed in an incubator on 

 the day they are laid may hatch in 480 hr. ; eggs of 

 Asiatic fowls placed in the same incubator when 2 wk. 

 old may hatch for 516 hr., a difference in time that makes 

 poor results inevitable if the eggs of both breeds are 

 incubated together. The eggs of ducks and of chickens 



