234 POULTRY BREEDING 
“The fifth and sixth generations, as shown in the chart, 
indicate only a few of the possible groups that may be 
obtained from various matings. Thus if the original sire 
and dam cannot be used for breeding purposes beyond 
the fourth generation their blood may be maintained in 
13/17 of its intensity by choosing parents from groups 
4 and 6, or 5 and 7, to produce groups 8 and 10 respec- 
tively. Then parents chosen from groups 8 and 10 will 
produce group 13, which is again mathematically 14 the 
blood of the original pair, and the original offspring again 
reproduced as far as blood lines are concerned. By 
choosing parents from 6 and 8 the male line contains in 
group 12, 27/32 of the blood of the original sire and 5/32 
of the blood of the original dam. By choosing parents 
from 7 and 10, 27/32 of the blood of the original dam, and 
5/32 of the original sire is produced in group 14. If it is 
deemed advisable to vary the proportions of the bloods 
of either side in any mating, groups 11 and 15 show that 
by selecting parents from 8 and 9, or 10 and 9, 21/32 of 
the blood of either line and 11/32 of the other may be 
obtained. Many other proportions may be worked out 
by combining different groups. 
“Tf it is advisable at any time to introduce new blood, 
it may be done satisfactorily by adding a female to any 
mating desired and distributing the new blood through 
her progeny. Thus by mating a female of outside blood 
(N) to male from group 8, there is produced group 16 
in which the offspring contains 1% new blood, 13/32 orig- 
inal sire blood and 3/32 blood of the original dam. It is 
a safer course to add new blood through a female than 
a male, as there is less danger of an entire mating being 
rendered worthless in case the blood does not combine 
to good advantage. 
