PRACTICAL AND SCIENTIFIC BREEDING 
time put on his chickens yield him an immediate income. 
Fanciers and Experiment Stations can well afford to use trap- 
nests and must, indeed, use them both for breeding for egg 
production, and also for determining the hen that laid the 
egg when full pedigrees are desired in other breeding work. 
A scheme that has sometimes been used in the place of 
trap-nests, is a system of small compartments, in each of 
which one hen is kept. Such a scheme does not seem feasi- 
ble on a large scale, but for breeders wishing to keep the 
records of a small number of hens, it is all right. Because 
of its cost, this system is wholly out of the question, except 
for a man following breeding as a hobby and who cannot de- 
vote himself during the day to the care of trap-nests. 
Having determined the best layers, it remains to breed 
from these and from their descendants. The tests of pbllets 
hatched from hens are better signs of the hen’s value as a 
breeder than is her own record. It has been surmised that a 
hen which lays heavily will not lay eggs containing vigorous 
germs. So far as the writer’s experience has gone, the laying 
of infertile eggs is a family or individual trait not particularly 
related to the number of eggs laid. 
When we have bred from the best layers and have raised 
our average egg yielder to a higher level, the question arises 
as to whether the strain will permanently maintain the high 
yield or drop back to the former rate of production. Theory 
says that it will not drop back. As a matter of fact it will 
not do so, for the heavier production will be more trying on 
the hen’s constitution, and naturally selection will gradually 
cause the egg record to dwindle. Hence the necessity of con- 
tinued selection or the infusion of new blood from other 
selected strains. 
Whatever may be the change desired in a strain of chick- 
ens, specimens showing the trait to be selected should be 
used as breeders. Those characteristics readily visible to the 
eye have long been the subjects of the breeder’s efforts. But 
traits not directly visible can likewise be changed by breeding. 
The number of eggs, size and color of eggs, rapid growth, 
ready fattening powers, quality of meat and general charac- 
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