Effect of a photoperiodic green light programme during incubation on embryo development and hatch process

Abstract

This study was conducted to evaluate the effect of a 12-h light, 12-h dark (12L : 12D) photoperiod of green light during day 1 to day 18 of incubation time, on embryo growth, hormone concentration and the hatch process. In the test group, monochromatic light was provided by a total of 204 green light-emitting diodes (522 nm) mounted in a frame which was placed above the top tray of eggs to give even spread of illumination. No light-dark cycle was used in the control group. Four batches of eggs (n=300/group per batch) from fertile Ross 308 broiler breeders were used in this experiment. The beak length and crown-rump length of embryos incubated under green light were significantly longer than that of control embryos at day 10 and day 12, respectively (P<0.01). Furthermore, green light-exposed embryos had a longer third toe length compared with control embryos at day 10, day 14 and day 17 (P=0.02). At group level (n=4 batches), light stimulation had no effect on chick weight and quality at take-off, the initiation of hatch and hatch window. However, the individual hatching time of the light exposure focal chicks (n=33) was 3.4 h earlier (P=0.49) than the control focal chicks (n=36) probably due to the change in melatonin rhythm of the light group. The results of this study indicate that green light accelerates embryo development and alters hatch-related hormones (thyroid and corticosterone), which may result in earlier hatching.

Exposing broiler eggs to green, red and white light during incubation

“…Factors such as temperature, humidity, turning and even carbon dioxide concentrations during incubation have been the most researched areas. These factors are extremely important, however, there is evidence that exposing embryos to light during incubation can have an effect on hatchability (Cooper, 1972;Shafey, 2004;Mench, 2014a and2014b;Archer, 2015a) and decrease incubation time (Ghatpande et al, 1995;Fairchild and Christensen, 2000;Tong et al, 2015). Light exposure has been seen to improve animal welfare posthatch as well (Archer et al, 2009;Özkan et al, 2012;Mench, 2014a and2014b).…”

Monochromatic Green Light Stimulation During Incubation Shortened the Hatching Time via Pineal Function in White Leghorn Eggs

“…Overall,monochromatic green light stimulation shortened the hatching time. Similarly, Tong et al [9] reported a 3.4 h shortened hatching time in broilers under monochromatic green LED light stimulation. Decreased hatching time was earlier linked to increase in hatching weight, differences in thyroid hormone levels, organ weight and maturity, post-hatching growth, feeding and general behavior [24][25][26].…”

“…Furthermore, providing monochromatic green light was shown to promote the growth of spleen [6] and skeletal muscle [7] in broilers. In addition, some studies have found a phenomenon that light stimulation during embryogenesis shortened the hatching time by using the light emitting diode lights (LED) [8,9]. The stimulating effect of monochromatic green light on skeletal muscle was linked to enhanced circulation levels of insulin-like growth factor 1 (IGF-1) in blood [7,[10][11][12].…”

Monochromatic green light stimulation during incubation shortened the hatching time via pineal function in White Leghorn eggs

“…Overall, monochromatic green light stimulation shortened the hatching time. Similarly, Tong et al [9] reported a 3.4 h shortened hatching time in broilers under monochromatic green LED light stimulation. Decreased hatching time was earlier linked to increase in hatching weight, differences in thyroid hormone levels, organ weight and maturity, post-hatching growth, feeding and general behavior [23,24].…”

“…Furthermore, monochromatic green light was shown to promote the growth of spleen [6] and skeletal muscle [7] in broilers. Additionally, some studies have reported that light stimulation using light emitting diode (LED) during embryogenesis shortened the hatching time [8,9]. The stimulating effect of monochromatic green light on skeletal muscle was linked to enhanced circulation levels of insulin-like growth factor 1 (IGF-1) in blood [7,[10][11][12].…”