Comparison of Lighting Regimens During Growth on Subsequent Seasonal Reproductive Performance of Broiler Breeders

The effects of daylight vs. incandescent lighting regimens during growth on responsiveness to seasonal light effects during lay were examined in three experiments. Broiler breeders were reared on an 8-h photoperiod from 1 to 20 wk of age. The photoperiod was produced by daylight supplemented with incandescent light (800 lx) or by using incandescent light only (20 lx). Birds were subsequently placed in curtain-sided breeder houses during autumn or spring. Birds grown with those of Experiment 1 were also housed in a total light control cage facility where constant or seasonal light environments could be simulated using computer-driven daily changes. Birds grown in incandescent light had greater egg production when lay started in autumn or in constant light environments than birds grown in daylight. Increased rate of lay was exhibited by birds grown in daylight when lay started in the simulated spring light environment. Egg specific gravity was significantly higher for birds grown in daylight than in incandescent light in both in-season and out-of-season experiments. Lighting regimens during rearing that improve laying performance of flocks commencing lay during autumn did not improve performance under spring conditions. These data suggest that the use of low intensity (20 lx) incandescent light during rearing increases the sensitivity of broiler breeders to fall and winter laying conditions.