CHAPTER XIX 

 BREEDING 



THE fundamental purpose of the breeder is to improve 

 his stock. There are two ways of doing this : first, through 

 better methods of care and feeding ; and second, through 

 the use of breeding animals which possess improved 

 "blood" or breeding. In this chapter the breeding side 

 only will be considered ; first, briefly the facts of reproduc- 

 tion and heredity as now understood, and second, the 

 application and bearing which these facts have on the 

 methods and practices of the breeder. 



THE LAW OF HEREDITY 



The process of reproduction. 



Every pig has his origin in the union of two germ-cells, 

 one produced by the sire and one by the dam. When these 

 two germ-cells, male and female, unite, a new individual 

 is born. This process is called fertilization, the successful 

 completion of which marks the real birth of the individual. 



The female germ-cell is called the egg or ovum (plural, 

 ova), and the male germ-cell the sperm or spermatozoon 

 (plural, spermatozoa). About every three weeks during 

 the breeding seasons the sow, if vigorous and in breeding 

 condition, produces and ripens a number of eggs, usually 

 from five to twelve. These are produced or secreted by 

 special organs, called ovaries, situated in the region of the 



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