The egg weight in the W light group was significantly (P < 0.05) greater than those in the R light group but were not significantly (P> 0.05) different in other light groups from 19 to 52 wk (Table 1).
The egg weight in W light was significantly (P < 0.05) greater than those in B light from 38 to 52 wk. Beginning at the age of 30 wk, the egg weight in W, B, and G light groups was consistently greater than those in the R light group throughout the remaining experimental stage (Figure 1A). These results were similar to the reports of Pyrzak et al. [4] for chicken but different from the reports of
Pyrzak and Siopes [5] for turkeys. The above results show that the R light produces smaller
eggs, whereas theWlight produces larger eggs.
In quail [6], long wavelength light had a stimulatory effect on the rate of egg production
without an adverse effect on egg weight.
In our study, the rate of egg production in B light was significantly higher than those in other light groups, but egg weight in the 4 light treatments was not significantly different from 19 to 37 wk (Table 1).
Inversely, the egg weight in the W light group was significantly greater than those in R light group, but rate of egg production in both light groups was not significantly different from 38 to 52 wk (Table 1).
So, our results support what Pyrzak et al. [4] suggested, that egg weight was affected by the light spectrumbut not by the rate of egg production.