Neda Nasirzadeh - Department of Animal Science, School of Agriculture, Shiraz University,۷۱۴۴۱-۶۵۱۸۶ Shiraz, Iran
Mohammad Javad Zamiri - Shiraz University۱Department of Animal Science, School of Agriculture, Shiraz University, ۷۱۴۴۱-۶۵۱۸۶ Shiraz, Iran
Amir Akhlaghi - ۱Department of Animal Science, School of Agriculture, Shiraz University, ۷۱۴۴۱-۶۵۱۸۶ Shiraz, Iran
Shahrokh Ghovvati - Department of Animal Science, Faculty of Agriculture, University of Guilan, ۴۱۶۳۵-۱۳۱۴, Rasht, Guilan, Iran.
Shahryar Kargar - Department of Animal Science, School of Agriculture, Shiraz University, ۷۱۴۴۱-۶۵۱۸۶ Shiraz, Iran.
Javad Amini - Senior Technical Advisor (Consultant) to Deputy Head of Livestock Production Improvement, Agricultural Organization, ۴۱۹۳۷-۱۳۷۳۱ Rasht, Iran.

Lighting is one of the important management factors affecting the health and welfare of birds. The objective of this study was to assess the effects of light-emitting diodes (LEDs) on production, reproduction, blood metabolites, immunology, and hepatic sterol regulatory element binding protein-۱ (SREBP۱) gene expression in broiler breeders. One-day-old Ross ۳۰۸ female breeder chicks (n=۱۰۰) were randomly assigned to ۲۰ light-proof pens and reared under five lighting regimens, including green (GL) or white (WL) LED at two exposure photophases (۸ or ۱۲ hours) as a ۲ ´ ۲ factorial experiment plus a control group (incandescent lamp at ۸L:۱۶D duration; CON). The LED color affected the feed intake during the rearing period, being higher in white than in green light; however, green light resulted in more medium and large white follicles on the ovaries, higher mean corpuscular hemoglobin concentration, and plasma cholesterol level. In WL۸ lighting, the relative weight of the bursa of Fabricius was higher (P≤۰.۰۵) than in CON birds. Plasma cholesterol level in GL۱۲ was higher compared to CON. Conventional and WL۱۲ regimens resulted in lower plasma alkaline phosphatase activity. Twelve hours of GL lighting resulted in higher eggshell weight and strength while it caused a small but significant decrease in egg shape index. Greater numbers of medium white (MWF) and large white (LWF) follicles were recorded in GL۱۲ birds, and there were more small white follicles (SWF) in GL۸ group (P≤۰.۰۵). The GL۱۲ and CON lighting resulted in higher concentrations of WBC and Hb compared with WL. Hepatic expression of SREBP۱ was higher in WL۸ birds. The results indicated that green LED improved egg quality while white LED caused higher relative weight of bursa and hepatic SREBP۱ expression, indicating the LED light may be beneficial to broiler breeder productivity. However, more studies are required to substantiate these findings.

LED light, egg quality, endocrinology, follicles, broiler breeder