The study was conducted concurrently with the
North Carolina Layer Performance and Management
Test (NCLP&MT), which evaluates the major commercial
layer strains used in the United States (Anderson,
2009). Four strains were selected from the
NCLP&MT at 101 wk of age. During the laying phase
from 17 through 101 wk of age, the hens were maintained
in accordance with the NCLP&MT housing
and phase feeding program (Anderson, 2009)