Abstract
Light is one of the important environmental factors affecting the growth, reproduction, and performance of poultry. It stimulates retinal photoreceptor cells to form visual imaging, enabling animals to adapt to external environments. Light also regulates non-visual physiological responses such as circadian rhythms, pupillary reflex, sleep regulation, and melatonin secretion. During the incubation, the photoreceptive functions of avian embryo have developed, and light stimulation at this stage affects embryo development and post-hatch performance. This paper mainly reviews the effects of light-emitting diode (LED) light exposure during incubation (light incubation) on embryo development, hatching performance, and post-hatch performance, along with the related mechanisms to provide insights for the research and practical application of light in poultry production.