no 



POULTRY PRODUCTION 



spring as possible, as good as possible, and at the least cost. 

 It is not only the easiest and cheapest form of breeding, but 

 also produces the most rai)id improvement. For market 

 purposes, grades are often the etjual of standanl-ljrcds. 

 For breeding purposes, grade males are usually worthless. 



The theoretical rapidity with wliicli the chanicteristics 

 of an improved breed are transmitted to ]3rogeny out of 

 the mongrels is illustrated in Figure 4.'). I'he percentages 

 given in each generation represent the hereditary constitu- 



FiQ. 45 



GRADING CHART 



tion of that generation with reference to the "l)lood" of 

 both the standard-bred bird and the mongrel. Of course, 

 the word " blood" does not imply the real blood of the animal, 

 but is a term used by the breeder to designate the sum total 

 of the hereditary characteristics. The actual results are 

 shown in h'igures 4(') to 49, and in Table X\'. 



It should be clearly understood that only when the male 

 is of a breed distinctly different from any represented in the 

 females and only in the first generation of the cross, does 



