Statistical Analysis
Data were analyzed by one-way ANOVA as a completely
randomized design using the GLM procedure of
SAS Institute (2003). Cage was used as an experimental
unit for analyzing the performance data, whereas
each bird selected was used as the statistical unit for
analyzing the data of lymphocyte subpopulations and
gene expression in the intestine. Differences among
means were tested by the least significant difference
method, and P < 0.05 was considered to be statistically
significant.