The present study was designed to explore the photoperiodic effect of intermittent lighting on various economic traits as well as egg quality traits initiating from post peak egg production in quails. This study was conducted at Avian Research and Training (ART) Centre, Ferozpur Road Lahore with both local and imported quails maintained under different continuous and intermittent lighting regimes. The experimental quails were subjected to 05 different lighting regimes viz., A (16L: 8D), B (8L: 6D: 2L: 8D), C (8L: 7D: IL: 8D), D (8L :7.5D: 0.5L: 8D) and E (8L: 16D) from 23 -34 weeks of age. The group E (8L: 16D) served as a negative control and group A (16L: 8D) was a positive control, while, the three intermittent lighting regimes used as experimental treatments were named as B, C and D. From 15th to 221I1 week the quails were maintained on a long day lighting schedule of (16L: 8D) in order to create uniformity among birds. The effect of these above mentioned lighting schedules on early productive performance of this flock of quails was examined in another study. In this trial the same act of treatments was used to investigate its lighting effect on post peak production (from 23 to 34 weeks). The experiment was conducted on 240 adult quails (23 weeks old) under factorial arrangements of 5 lighting regimes x 4 purebred strains x 3 replicates having 4 quails (1 male: 3 female) each. The experimental quails were maintained in a 5 tier quail battery (each tier had 6 decks). The study was conducted under the same manage mental conditions. The weekly data on body weight, egg production, FCR (for egg production and egg weight), egg quality traits (egg weight, shell weight, shell thickness, haugh unit and yolk index were recorded. The data thus collected were statistically analysed using analysis of variance technique and comparison of means was made using DMR test.

The results of the present study show that mean body weight under light regimes A, B, C, D and E was recorded as 268.81 (+5.09), 280.70 (+12.3), 267.96 (+2.99), 274.10 (+12.3) and 271.20 (+10.3)gm, respectively. A significant (p<0.Ol) effect of light treatments on body weight was observed. The highest body weight (280.70+12.3gm) was recorded under treatment B (8L: 6D: 2L: 8D)which was found to be significantly better than recorded under other treatments, however, A and C and D and E differed non- significantly from each other. Breed differences in body weight were observed to be significant (p<0.Ol). Significantly (p
The mean egg production of quails under lighting regimes A (16L: 8D), B (8L: 6D: 2L: 8D), C (8L: 7D: 1L: 8D), D (8L: 7V2D: V2L: 8D) and E (8L: 16D) during the experimental period was recorded as 79.49, 74.65, 75.99, 76.33, 75.64 percent, respectively. The effect of lighting treatment was found to be significant (p more eggs when compared with birds on experimental treatments. The results indicated that light treatments of quails during growing period significantly (p 2L: 8D) produced significantly (p The results of the study in respect of other egg quality traits such as Haugh unit, egg shell weight, yolk diameter and albumen height showed non-significant effect ofdifferent lighting regimes applied during experimental period. The effect of breed and light into breed interaction was found to be non-significant.