YUMURTA TAVUKLARINDA KULUÇKA DÖNEMİ FOTOPERİYODİK AYDINLATMANIN HİPOTALAMUSTA IŞIĞIN ALGILANIŞI (VA OPSİN) SEROTONİN TRANSPORTER SİSTEMİ (5-HTT) VE STRES (CRH)İLE İLİŞKİLİ GEN EKSPRESYONUNA VE KEMİK BİLEŞİMİNE ETKİSİ
Project no. 901 · Status: Kapanmış · 2018
Summary
In this study, the effect of cyclic lighting (16 h light 8 h dark, 16L:8D) during the incubation using WHITE and GREEN LED lamps on expression of VA opsin which is known to be involved in extra retinal photoreception and reproduction, serotonin transporter (5-HTT) and stress specific CRH genes have been investigated in egg type chickens at hatching day, before egg production (16th week), and during the egg production (40th week). At the same ages, tibia bones have been collected for to measure bone growth (length, width) bone strength and bone composition (dry matter, ash, Ca and P%). DARK incubation condition has been used as control group. Incubation lighting affected 5-HTT and CRH expression at hatch (P<0.05) and 5-HTT expression in chicks from GREEN was significantly higher than WHITE but was similar to the DARK. WHITE group had higher CRH expression level than that of DARK and GREEN groups P<0.05). VA opsin expression did not differ with incubation lighting at hatch. Before the egg production, at 16th wk, there was no significant effect of incubation lighting on gene expression. During the egg production VA Opsin expression was significantly higher in WHITE group as compared with the other two groups. Expression of CRH which mediates stress response of body reduced in GREEN group as compared to DARK and WHITE groups (P<0.05). Incubation lighting did not affected bone traits except with the bone dry matter at egg production period. Hens from GREEN had higher dry matter content in tibia bone (P<0.05). Results from this study supplied first evidences of that incubation lighting and color of light might have long lasting effects on stress and serotonin systems and extra retinal light perception. GREEN group had higher 5-HTT but reduced CRH expressions at hatch while WHITE group had higher CRH expression both at hatch and egg production period. WHITE group also had higher VA opsin expression at 40th wk, These findings are shown first time in egg type chickens and may indicate possible relations among the lighted incubation and stress response, serotonin system and feather pecking behavior. Key Words: Lighted incubation, laying hen, VA opsin, 5-HTT, CRH, tibia