RESULTS
Live Performance, Sexual Maturation,
and Egg Production Traits
The effects of the lighting treatments on BW, feed
intake, and mortality rate are presented in Table 2.
There were no significant differences in initial BW, fi-
nal BW, feed consumption, or mortality rate among
the treatment groups. Table 3 shows the effects of the
light treatments on sexual maturation and egg produc-tion. The DF treatment significantly delayed the onset
of egg laying from that observed in the R and DR treat-
ments. The R and DR birds started to lay at 3.2 and
4.7 d following photostimulation, respectively, where-
as DF birds commenced laying at 8.7 d (P = 0.029).
However, no significant difference was observed in the
weight of the first egg among the treatment groups.
The number of eggs produced per hen during the first 8
wk of photostimulation was significantly greater for the
R treatment group (25.9 eggs) as compared with that
of the DF (19.5) and DR (20.9) treatment groups (P =
0.030). There were no significant differences in total egg
production during the 26-wk egg-laying period among
the treatments, although the number of eggs produced
by the DF hens (65.8 eggs/hen) was numerically less
than that of the DR (76.5) and R (76.2) birds.
Means of egg weight, yolk weight, yolk color, albumen
weight, albumen height, shell weight, shell thickness,
and egg specific gravity over the experimental period
are summarized in Table 4. No effect of lighting treat-
ment was found within the hen performance criteria
of egg weight, egg and eggshell quality, or egg specific
gravity among the treatment groups.