Led Poultry Lighting: Effect of Light in Poultry Production
Directory:
1. Benefits of Led Poultry Lighting
2. Photosensitive Structure of Poultry
3. The Effects of Various LED Light Colors on Poultry
4. The Effects of LED Light Cycles on Poultry
5. The Effects of Various LED Light Intensities on Poultry
6. The Effects of Various LED Light Color Temperatures on Poultry
As the breeding industry evolves and environmental protection standards become stricter, an increasing number of open farms are transitioning to intensive closed breeding systems. This shift means that essential natural conditions for poultry growth—such as light, air, temperature, and humidity—must now be artificially controlled. To maximize production efficiency, it is crucial to create an optimal breeding environment for poultry, with lighting conditions being a particularly challenging aspect. Farmers often struggle to determine which type of lighting equipment is best suited for poultry farming, given the variety available on the market.
1. Benefits of Led Poultry Lighting
LEDs offer numerous benefits, including:
1.1 Energy Efficiency: LED lighting significantly reduces energy consumption compared to incandescent, fluorescent, or halogen lamps, using ultra-bright, high-power LED sources and efficient power supplies to save over 80% of electricity compared to traditional incandescent bulbs, while providing ten times the brightness at the same power level.
1.2 Flicker-Free Operation: LEDs operate on pure DC power, eliminating the flickering that can cause visual fatigue associated with traditional light sources.
1.3 Reduced Visual Fatigue: Advanced light distribution technology transforms the LED light source into a surface light source, increasing the emitting surface area, reducing glare, and enhancing visual comfort.
1.4 Eco-Friendly: LEDs do not contain harmful substances like lead or mercury, making them environmentally safe.
1.5 No UV or Infrared Radiation: LEDs are harmless to human health as they do not emit ultraviolet or infrared radiation.
1.6 High Luminous Efficiency: With a luminous efficiency of up to 80 lm/W, LEDs offer a range of color temperatures and can emit various colors, including red, yellow, blue, green, cyan, orange, purple, and white, with excellent color rendering properties. These benefits have led to a growing adoption of LEDs in production and breeding.
Environmental factors influencing poultry growth include humidity, temperature, ventilation, and light, with research indicating that light plays a particularly significant role. Poultry are more sensitive to light than humans due to their unique eye structure. Many poultry producers acknowledge the critical role of lighting in enhancing performance. Whether for chickens, turkeys, laying hens, or broilers, all poultry require appropriate light stimulation to promote healthier growth and improved production outcomes. Therefore, it is essential to scientifically and reasonably adjust the lighting environment for poultry.
2. Photosensitive Structure of Poultry
The eye serves as a primary sensory organ for poultry. The retina of poultry is rich in photoreceptor cells, which fall into three categories: rod cells, single cone cells, and double cone cells. Single cone cells are further classified into four types: red, blue, green, and purple cone cells. These cells play a crucial role in enabling poultry to perceive colors and can detect wavelengths ranging from ultraviolet to red. In contrast to humans, who can only perceive visible light wavelengths between 400 and 730 nm, poultry can detect a broader spectrum, including ultraviolet light (320 to 400 nm), which is invisible to humans. The precise functions of the cone cells are not fully understood, but they are believed to help adjust light intensity and detect movement. Given poultry's color perception capabilities, using LED lights that emit various colors can enhance the light stimulation necessary for their growth, development, and reproduction. While humans may not notice flickering in lighting, poultry can perceive it as a potential threat from predators. Reducing or eliminating flicker creates a safer and more comfortable environment for poultry, significantly lowering stress levels. Fluorescent lamps tend to flicker, whereas high-quality LEDs do not. Transitioning from fluorescent to flicker-free LED lighting can greatly alleviate stress in poultry flocks, leading to improved production performance, decreased undesirable behaviors like pecking, and enhanced disease resistance, ultimately reducing mortality rates.
Extraretinal photoreceptors in birds are crucial for regulating their biological clock, which establishes a daily pattern of hormone secretion that influences behavior, physiology, and reproduction. Light stimulation activates photoreceptors in the retina, sending signals to the hypothalamus via the optic nerve, or it can directly stimulate extraretinal photoreceptors through the skull, generating nerve impulses that reach the pineal gland and hypothalamus. When light signals reach the pineal gland, they stimulate it to help regulate daily behavioral cycles. Additionally, light signals to the hypothalamus activate photoreceptors that trigger the release of gonadotropin-releasing hormone (GnRH). GnRH then travels to the anterior and posterior pituitary through the hypophyseal portal vein system, leading to the secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which regulate metabolism and reproduction. This process ultimately impacts poultry behavior and rhythms, enhancing their growth, production performance, reproductive function, and activities. Recent studies suggest that LED lighting, known for its monochromaticity, high efficiency, and low energy consumption, has become the preferred choice for farmers. Utilizing LED lights for controlled light stimulation can significantly improve poultry production performance by maintaining optimal hormone levels.
3. The Effects of Various LED Light Colors on Poultry
The growth and production efficiency of poultry can be influenced by different lighting conditions, primarily because these conditions can alter biochemical markers and nutrient absorption in the birds. Poultry possess a unique photosensitive structure, allowing them to perceive colors differently than humans, with a heightened sensitivity to red and blue wavelengths.
In a study on broiler chickens, Prayitno et al. provided four different light colors—red, blue, green, and white—at an intensity of 30 lx, allowing the chickens to choose their preferred lighting for growth. The findings indicated that chickens favored blue and green lights, exhibiting calmer behavior under these conditions. Similarly, Wang Yue et al. raised Xiaoshan broilers under various colored light environments, including a control group with incandescent light, as well as red (700 nm), yellow (580 nm), green (550 nm), blue (470 nm), purple (420 nm), and white (400-760 nm) LED lights. Their experiment revealed that broilers under yellow LED light had the highest cumulative weight gain and feed conversion rates, while producing the least amount of manure. As research has progressed, studies on monochromatic light have increasingly shifted towards exploring combinations of light colors at different growth stages. For instance, Pan Jinming et al. implemented an intelligent LED poultry lighting system that provided various colors of light to broilers at different developmental stages, demonstrating that specific colors were more effective for broilers at different points in their growth.
In their research on breeding and laying hens, Min et al. discovered that hens exposed to red LED light produced more eggs compared to those under white and blue light. Additionally, the egg production rate and eggshell thickness were enhanced under red light. Kim et al. examined the impact of LED light colors on Hailan brown-shell laying hens and found that those under red light began laying eggs significantly earlier than those under incandescent or blue light, with a notable increase in egg production. Conversely, blue light delayed the onset of laying, suggesting that red light can accelerate sexual maturity and boost egg production in laying hens. Retesa et al. noted that red LED lamps could enhance testicular development in quails during puberty, while the type of lamp did not influence sperm quality or fertility in male quails, indicating that red LED lamps can reduce the time to sexual maturity in quails. Wang Xiaoshuang's study on "Meihuang" breeders revealed that the second-generation breeders performed better when exposed to red and green LED lamps. Red LED light advanced the age of laying, resulting in higher fertilization and hatching rates, as well as increased average weekly egg production, while minimizing the occurrence of deformed and soft-shelled eggs. In contrast, green LED light delayed the age of laying but improved fertilization rates and egg quality metrics such as eggshell thickness, egg weight, and Haugh unit.
Research indicates that poultry exhibit different behaviors under various light colors. Qi Xianli's study found that red and blue light effectively suppressed chickens' pecking behavior, which remained consistent regardless of light intensity changes. Yuan Qingyan et al. illuminated snow mountain chickens with LEDs of different colors and found that those under blue-green LED light had significantly greater crown heights compared to those under warm red and warm yellow light (P<0.05), and the incidence of feather pecking was much lower under blue-green light than the other two colors.
In conclusion, providing meat and breeding poultry with appropriate light color conditions at different stages can significantly enhance their production efficiency.
4. The Effects of LED Light Cycles on Poultry
In the wild, animals' reproductive development is influenced by sunlight and seasonal climate changes. In controlled breeding environments, humans manage the lighting conditions, which can be categorized into two types: intermittent light and continuous light. Intermittent light can be further divided based on various timing patterns, primarily into decreasing and increasing light cycles. Research indicates that intermittent light is more advantageous for poultry growth compared to continuous light, as it can lower both morbidity and mortality rates. For seasonal breeders like geese, studies have shown that adjusting the light cycle can alter their breeding season and extend breeding times. For instance, when the light duration for Xingguo Grey Geese is increased, prolactin (PRL) levels rise while luteinizing hormone (LH) levels drop; conversely, reducing light duration leads to decreased PRL and increased LH.
Comparative studies reveal that a decreasing light cycle can enhance poultry weight to some extent, while an increasing light cycle may hinder growth. Other research indicates that shorter light durations can stimulate reproductive activity in Guangdong Grey Geese, whereas longer durations can suppress it. In one study, Magang geese were provided with 18 hours of supplemental light per day in December, a time when natural light is limited, leading to an early onset of the non-breeding period and molting. By March, the light duration was reduced to 11 hours per day, and after about a month of this shorter light exposure, the mother geese resumed laying eggs.
A comparison of three different light sources—white LED lamps, white mini fluorescent lamps, and yellow incandescent lamps—on the production performance and egg quality of laying hens under identical light cycles showed that the type of light source did not significantly impact the final weight, feed intake, egg production, egg morphology, or protein levels in the hens. Thus, the influence of LED light cycles on laying hens aligns with that of traditional lighting sources.
The light cycle can influence the feeding habits and behavior of poultry. Implementing an appropriate light cycle can effectively regulate feed intake and optimize egg production. Among the various light cycles commonly utilized (12L: 12D, 16L: 8D, and 20L: 4D), the 16L: 8D cycle is the most frequently adopted as a balanced option. Research has indicated that this light cycle can enhance poultry welfare, alleviate psychological stress, boost immune responses, and increase vitality. Intermittent lighting not only lowers lighting expenses but can also maintain or even enhance the egg-laying performance of hens.
In broiler production, the typical light cycle is 23L: 1D. This cycle significantly boosts body weight compared to the limited light duration cycle (12L: 12D), although it also increases the feed consumption to weight gain ratio. Research suggests that different light cycles should be applied at various growth stages of poultry. Notably, the 12L: 12D cycle yields better survival rates, average weights, and feed conversion rates for broilers compared to the 20L: 4D cycle, while intermittent light cycles can help reduce stress in poultry.
Utilizing adjustable lighting to mimic sunrise and sunset creates a more comfortable environment for poultry, facilitating a smoother transition between sleep and wakefulness. Modern LED technology allows for seamless dimming from 0 to 100% of maximum brightness, making it easy to achieve sunrise and sunset effects with LED lights and programmable dimmers.
5. The Effects of Various LED Light Intensities on Poultry
Poultry are highly responsive to different light intensities, which can influence their activity, behavior, immune function, growth rate, and survival. Research has indicated that when observing laying hens at light levels of 5 lx and 50 lx, the incidence of feather pecking and aggressive behaviors was significantly greater at 50 lx, suggesting that high light intensity should be avoided in hen houses. Excessive light can overstimulate poultry, leading to undesirable behaviors such as restlessness, increased activity, pecking, and prolapse. Conversely, low light levels can promote growth in poultry over a short period, but prolonged exposure to very low light can result in inactivity, hindering physical development. Reducing light intensity has a more pronounced positive effect on poultry health. Additionally, variations in LED light intensity can significantly impact poultry feed intake and feed conversion rates. For instance, studies have shown that Beijing ducks under 5 lx light conditions have a higher breast muscle rate compared to those under 40 lx, which enhances feed conversion and improves meat quality in terms of redness and brightness.
For caged broilers and laying hens, optimal production performance and welfare are observed when the average light intensity of LED lamps is between 6 to 25 lx, with 20 lx being particularly beneficial for stacked cage laying hens. In experiments with broilers at light intensities ranging from 9 to 15 lx, the overall production performance was minimally affected. Ye Jietian's research on egg-laying performance at light intensities of 16.4 lx, 10.2 lx, and 6.8 lx revealed that laying hens can maintain normal production levels at 10.2 lx.
6. The Effects of Various LED Light Color Temperatures on Poultry
In addition to light intensity (light/dark conditions), the color temperature of light significantly influences poultry production. Poultry can detect different wavelengths of light, which can enhance the peristalsis in their small intestines, improve food digestion and energy absorption, and enable more efficient feeding and healthier growth. In broiler farming, Riber found that Ross 308 broilers thrive better under cool white light compared to 4100K neutral white and 6065K cool white LED lights. Olanrewaju's research on broilers raised with 2700K warm LED, 5000K cool LED, and 2010K incandescent bulbs indicated that broilers under the 5000K cool LED outperformed those under incandescent lighting in terms of weight, although there were no significant differences in feed intake, feed conversion rates, or mortality. Additionally, the variations in performance indicators between the two LED color temperature groups were not substantial.
Research indicates that a color temperature of 5000K (cool white light) can increase poultry activity and encourage feeding, making it ideal for maximizing growth rates. Conversely, a color temperature of 2700K (warm white, akin to a traditional 60W incandescent bulb) has been shown to optimize egg production. LED lighting can fulfill both requirements.
The longevity of LED products contributes to their cost-effectiveness. High-quality LEDs can last at least five years, leading to energy and maintenance savings. An optimal lighting system should replicate the daylight spectrum, offer smooth dimming to simulate sunrise and sunset, provide a color temperature suitable for the poultry's developmental stage, and minimize flicker. This demonstrates the welfare and performance benefits of LEDs, making them increasingly attractive to breeders.
Since lighting is crucial for poultry production and welfare, it is essential to select a lighting supplier experienced in the poultry sector, capable of delivering high-quality, adaptable LED products and customized lighting designs for each specific operation.