BREEDING 113 



BREEDING METHODS. 



In general, breeding is carried on in the hope of securing 

 improvement in one of three ways: (1) by transferring the 

 valuable characteristics of an improved breed to common 

 stock; (2) by impressing the excellencies of superior indi- 

 viduals on other families within the breed, so as to produce 

 a higher average excellence in them than on the average is 

 possessed by the breed itself; (3) by securing a new associa- 

 tion of characteristics, that is, producing a new breed. The 

 first is the way of the producer and the method is grading. 

 The second is that of the breeder and the method is "line 

 breeding." With the third, the method is cross-breeding. 



Grading. — By grading is meant the practice of mating 

 standard-bred males with mongrel or relatively unimproved 

 females. Technically speaking, the reciprocal cross is also 

 grading, but, practically, it need not be considered. 



Grading is the method of the producer because it lends 

 itself most readily to his purpose of securing "as many off- 

 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 rapid improvement. For market 

 purposes, grades are often the equal of standard-breds. 

 For breeding purposes, grade males are usually worthless. 



The rapidity with which the characteristics of an improved 

 breed are transmitted to its progeny from the mongrels is 

 illustrated in the accompanying chart. The percentages 

 given in each generation represent the hereditary constitu- 

 tion of that generation with reference to the "blood" of 

 both the standard-bred bhd 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. 



It should be distinctly 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 

 the percentage given in the table directly represent anything 

 of the hereditary constitution of the individual. After that 

 there will be great variability in the characteristics trans- 

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