The effect of two different green lighting schedules during embryogenesis on myogenesis in broiler chickens

Abstract

Abstract Light is one of the factors that interfere with avian development as early as during embryogenesis. The aim of this study was to determine the effect of monochromatic green light on hatchability, body weight and breast muscle myogenesis in broiler chickens, as expressed by breast muscle weight, muscle fibre thickness and number of satellite cells (Pax7 +) on d 1, 4 and 8 of life. Lighting programmes investigated were two different light cycles of 30 minutes of light and 30 minutes of darkness (L1 30/30), 12Â h of light and 12Â h of darkness (L2 12/12) and one control group (C) of continuous darkness applied throughout embryogenesis until day 18 of incubation. Green light was found to have a positive effect, resulting in significantly greater body weight of the exposed chickens (group: L2 12/12 – on d 4 of age; group L1 30/30 – on d 8 of age), and highly significantly greater fibre thickness in breast muscle in group L1 on d 8 of age. Photo-stimulation exerted a significant effect on the number of Pax7 + cells per unit of muscle cross-sectional area in broiler chickens on d 4 of life. However, higher body weight tended to be accompanied by a decrease in the number of Pax7 + satellite cells, calculated per unit of muscle area. This indicates the fusion of satellite cells with existing muscle fibres, which leads to an increase in their diameter. Based on the obtained results, we conclude that there is a potential opportunity to regulate the growth and development of chicken skeletal muscle by light during embryogenesis. This may further increase the effectiveness of chicken meat production. However, more research is needed in order to find the most optimal lighting treatment.