PRINCIPLES OF POULTRY BREEDING 83 



departed from. If uniformity of excellence in laying is 

 desired, the object will be quickest secured by using each 

 year a male that has a good pedigree in that respect. 

 Changing the breed or type of male each year will result in 

 getting nowhere. The failure to make the most of grading 

 has been due to the occasional or frequent use of grade 

 males. 



A grade may have apparently all the characteristics of 

 the pure-bred ; he may look so attractive that the breeder is 

 tempted to take a chance and use him for breeding, with 

 the result that improvement is likely to go backward. The 

 grade may himself have all the characteristics, but he has 

 not the ancestry or blood lines behind him to insure the 

 transmission of those qualities, and instead of grading up, 

 the process is liable to become mongrelizing. It should also 

 be clearly understood that the male should not only be pure- 

 bred, but he should have that purity of breeding that ex- 

 tends to egg-laying; in other words*, he should be from a 

 strain that is known to consist of good layers. 



Prepotency. The reason a grade male may not transmit 

 his characteristics has been ascribed to a lajck of what is 

 called prepotency. Prepotency, therefore, is the ability of 

 the parent to fix his characteristics in the offspring. All 

 parents have not this power in the same degree. This is the 

 significant fact for the breeder. It is not enough to know 

 that a certain male or female has a long pedigree, or that 

 the blood lines have been carefully preserved for years. 

 Prepotency does not always follow blood lines. Later knowl- 

 edge has given a modified meaning to prepotency, and the 

 fact has been proved that one individual may be prepotent 

 and another of the same blood lines, possibly of the same 

 parentage, is not. It is true that the individual having been 

 bred pure to a certain type for a great many generations is 

 more likely to transmit his characteristics than would a 



