Influence of LED light spectra and photoperiods on performance, bone characteristics and related genes expression in broiler breeders.

1. Lighting is a crucial environmental factor in poultry production. This study evaluated the effects of light-emitting diodes (LED) on performance and several bone characteristics, including bone mineralisation, morphometry, histology and selected gene expression in broiler breeders.2. A total of 800 one-d-old female broiler breeder chickens (Ross 308) were randomly allocated to one of 20 light-proof pens and reared under green (GL) or white (WL) LED light for two photophases (8 or 12 h) in a 2 × 2 factorial experiment and compared to a control group (incandescent lamp at 8 L:16D duration; CON). Weight gain, feed consumption and feed conversion ratio (FCR) were calculated. Femoral and tibial characteristics were measured.3. The LED colour affected feed intake during the rearing period, being higher for birds under white compared to green light. Tibial calcium (Ca) concentration in WL birds was lower than for green LED lighting regimens but not different from the CON group ( ≤ 0.05). Birds under 12 h lighting had greater tibia bone dry matter and trabecular separation (mm) than those in the 8 h groups. However, bone volume fraction and trabecular number per mm in 8 h birds were higher than in 12 h groups ( ≤ 0.01). There was greater expression of the gene under WL compared with CON. expression in WL8 was 4.63 times greater than in the CON group ( ≤ 0.05). The gene expression in WL12 was higher than in the CON group ( ≤ 0.05).4. Exposure to white and green LED spectra enhanced bone gene expression and mineralisation, respectively, without adverse effects on bird performance. Thus, LED light may be beneficial to broiler breeder bone traits.