BREEDING SYSTEMS 



249 



tions of weak birds may be used, and this will speedily ruin all 

 past and future results. Line breeding is one of the best systems 

 for improvement if understood and correctly managed. The 

 chart (Fig. 126) will enable the poultryman to understand the 

 system, so that he may proceed in safety and get sure results. 



J^AJLE LINE 



FEMALE LINE 

 BREEDING CHART y ) /^^ 



2nd 



3rd 



Ve -fth 



Fig. 120. — Line-breeding chart. In this chart the black and white' circles and seg- 

 ments represent the blood Unas, black standing for the male line and white for the female 

 line. The solid black hnes represent that a male has been chosen from the group from which 

 they start and the dotted hnes that a female has been chosen. The cross-Hned circle at 

 the left shows what takes place when out-crossing or the bringing in of new blood lines is 

 practised. (After I. K. Felch.) 



Out-crossing, as generally practised, is the use of a male bird 

 of unrelated blood with females of the same breed which have 

 been in-bred or line-bred for a number of generations. It does 

 not mean the introduction of blood of a different breed, but of 



