120 POULTRY PRODUCTION 



cannot be done in the case of a correspondingly unusual 

 bird. The nearest tliat the poultry breeder can approach 

 this is by niatino; such a bird to its own progeny and founding 

 a family whose blood lines carry a preponderance of its influ- 

 ence. 



The purpose of line breeding is to purify and render per- 

 manent in the breed some highly desirable C|uality or quali- 

 ties of an individual or family. 



In somewhat the same way that the continued use of 

 standard-bred males raises the average quality of a flock 

 of mixed breeding by fixing standard-bred qualities, the 

 continued mating of an unusually excellent breeder with 

 offspring of his or her own get, or even a more indirect 

 introduction of that individual's blood, tends to raise the 

 quality of further ofl'spring to as high grade of excellence 

 as either of the original parents, by fixing the characters 

 of the parent whose blood is most desired. 



Felch's Breeding System. — A well-known practice in poul- 

 try breeding is that represented in the very excellent chart 

 adapted by J'ierce from one worked out by Telch, a veteran 

 Light Brahma breeder, and shown in k'igure 53. 



In this chart the breeding operations are represented as 

 beginning with a pair of unrelated birds which are indicated 

 by the circles "A" and " B." Throughout the diagram, 

 solid black indicates the average proportion of blood of the 

 original male A . In the same manner, \\hite always indicates 

 the average proportion of blood from the original female B. 



Thus the members of group C, which are offspring of the 

 original pair, will on the average receive half of their inheri - 

 tance from each parent. If a pullet from group C is now 

 mated with her sire A, the resultant offspring represented 

 at D will, on the average, carry 75 per cent of the character- 

 istics of the original male. If now a pidlct from group ]) is 

 mated with the original sire A, the progeny represented at 

 /'' will, on the average, carry 87.5 per cent of the character- 

 istics of the original male and but 12.5 per cent of those of 

 the original female. 



In exactly the same way males from groups C and E n)a\' 

 be mated back to the original female B with correspond- 

 ing results. 



