Poultry Farm Lighting: Characteristics of Lighting for Poultry Farm
Directory:
1. Spectrum of Poultry Farm Lighting
2. Light Intensity of Poultry Farm Lighting
3. Light Cycle of Poultry Farm Lighting
In poultry farming, various factors influence the growth of birds, which can be categorized into physical and chemical factors. Physical factors include temperature, humidity, light, dust, and the internal environment, while chemical factors encompass carbon dioxide levels and harmful gases like ammonia and hydrogen sulfide. Since poultry growth is an irreversible process, it is essential to conduct extensive research to understand the impact of these factors, with light being particularly crucial. Proper light management plays a vital role in poultry development.
Poultry have a more advanced visual system than humans due to their unique eye structure, making them more sensitive to light than mammals. Three key aspects of light control in poultry farming are the spectrum, light intensity, and light cycle. These elements significantly affect the growth performance and behavior of poultry. An effective and standardized lighting system for poultry farming should generate a composite light spectrum that supports their growth and accurately regulate light intensity and cycles based on their developmental needs.
1. Spectrum of Poultry Farm Lighting
Numerous researchers, both domestically and internationally, have demonstrated through extensive experiments that various light spectra have distinct impacts on poultry growth, with blue and green light spectra showing particularly pronounced effects.
Rozenboim and colleagues found that broilers raised under green and blue light conditions outperformed those under traditional lighting without specific spectra. Professor Chen Yaoxing conducted experiments using LED lights, comparing a control group with a spectrum of 400-760nm to an experimental group with spectra of 660nm, 560nm, and 480nm. The results indicated that lighting with 480nm or 560nm spectra promotes early growth and development in broilers while also improving the feed-to-meat conversion ratio; notably, 480nm lighting significantly enhances later growth as well.
Additionally, Cao et al. suggested that green and blue light boost serum testosterone levels, aiding the growth of commercial broilers. Xie et al. found that broilers exposed to blue light exhibited better feed efficiency, while Halevy et al. observed that green light stimulation during the embryonic stage significantly increased the number of satellite cells in the muscles of broilers within 1-3 days post-hatching. Under green light, the breast muscle fibers of broilers were more uniformly sized, exhibited stronger differentiation synchronization, and demonstrated greater developmental potential. Prayitno et al. investigated the effects of 30 different light colors, including blue, green, red, and white, on broilers and concluded that blue and green light are more beneficial for their growth compared to red and white light, with blue-green light particularly effective in keeping birds calm.
2. Light Intensity of Poultry Farm Lighting
In poultry farming, light intensity is typically measured in lux, which indicates the amount of light received per unit area. Adequate light intensity is essential for the healthy development of poultry. Some farmers may opt to lower light intensity to accelerate fat accumulation in birds. However, excessively low light levels can have adverse effects, such as decreased water and feed intake, leading to stunted growth.
Research has shown that the behavior of broilers is influenced by light intensity; higher light levels tend to increase their activity, while lower levels can help control aggressive behaviors like fighting and feather pecking. Nonetheless, if the light intensity drops below 1 lux, it can significantly hinder chicken activity and normal growth.
A modern lighting system developed by Liu and colleagues suggests maintaining a light intensity of 20 lux for the first six days of broiler growth, followed by 5 lux from day seven until the end of the growth period. This study also indicated that broilers perform better under intermittent lighting compared to continuous lighting. Ahmad et al. found that light levels above 50 lux in later stages enhance hens' sexual maturity, while Deep et al. determined that 5 lux is the minimum effective light intensity based on a comprehensive assessment of broiler production performance, breast muscle yield, and welfare.
3. Light Cycle of Poultry Farm Lighting
Various light cycles impact poultry differently. While numerous studies have been conducted on this topic, there is no standardized light cycle for poultry farming, either domestically or internationally. Poultry farming typically employs continuous and intermittent lighting; however, excessively long periods of continuous light can lead to negative effects, such as increased nervousness and lethargy in broilers, which can hinder their essential behaviors and overall growth. Reducing continuous light duration can enhance broiler growth and support their healthy development. Intermittent lighting is more prevalent globally.
Aviagen recommends the Ross x Ross 308 photoperiod for broiler farming as follows: the first week (23 hours of darkness and 1 hour of light), the second to fourth weeks (20 hours of darkness and 4 hours of light), and from the fourth week onward (23 hours of darkness and 1 hour of light). Here, "D" indicates the dark period when the lights are off, allowing broilers to rest, while "L" signifies the light period when the lights are on, enabling broilers to eat and engage in normal activities. Research by Bayram et al. found that using a restrictive lighting scheme of 16 hours of light and 8 hours of darkness, or a repeated intermittent lighting pattern of 1 hour of light and 3 hours of darkness, can enhance breast muscle weight, promote growth, and improve feed conversion efficiency in broilers.
The influence of the spectrum on poultry is mainly concentrated near the wavelengths of 460nm and 560nm, that is, the blue-green light spectrum, but the spectrum of other wavelengths will also have a certain impact on the growth of poultry, indicating that the spectrum that affects the growth of poultry is a composite spectrum. The effect of light intensity on poultry growth is generally that the light intensity is relatively strong in the early stage, gradually weakens in the later stage, and finally decreases to the minimum. The minimum light intensity is generally 5lux. Although there is no clear conclusion on the effect of light cycle on poultry growth, it is certain that restricted light or repeated intermittent light can promote poultry growth, and different users can determine a relatively reasonable light cycle table based on experience. The control of light intensity and light cycle is relatively easy to achieve. This article focuses on the effect of spectrum on poultry growth, further analyzes and studies the light sensitivity curve of poultry eyes, and designs a composite spectrum based on the synthesis of multiple monochromatic LEDs on this basis.