CHAPTER II 

 PRINCIPLES OF SWINE BREEDING 



Swine breeding. While swine breeding is a science in 

 so far as it concerns biological functions and processes 

 and evolution, it is an art in practice. The practice of 

 swine breeding consists in the development of those 

 characteristics which are of value to man. In order to 

 accomplish this, the characteristics must be possessed by 

 the animal to start with. Our improved breeds of swine 

 would never have attained their present degree of per- 

 fection had not the high capacity for feed utilization been 

 inherent. This capacity has been cultivated and 

 developed. 



Selection. Progress in swine breeding has been made 

 by artificial and methodical selection based on utility. In 

 this selection both individuality and pedigree have been 

 considered. This selection has enabled the breeder to 

 favor and propagate desirable variations and to avoid the 

 more undesirable ones. Natural selection has also played 

 an important part in the development of breeds of swine. 

 The application of the law of "the survival of the fittest" 

 proceeds in the domesticated as well as in the wild state, 

 but in the domestic state it comes nearer being "the sur- 

 vival of the best," since our efforts at artificial selection 

 are toward the favoring and fixing of those tendencies 

 of special value to man. Thus the progress in breeding 

 swine is dependent on the making of those selections of 

 value to man, depending upon heredity to fix the selected 

 qualities or characteristics. 



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