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Lighting in poultry production holds notable importance with the advancement and modernization of the industry, as it plays a significant role in the physiology and growth of broiler chickens. Increasing attention has been paid to the impacts of lighting management on growth performance, immune status, and welfare of meat-type chickens. It is essential to have an appropriate lighting regimen that includes the light source, intensity, duration, and wavelength of light to improve broilers' growth and behavior. By manipulating various physiological, immunological, and behavioral activities, altering the color of light has been acknowledged as a potent managerial strategy capable of mitigating an array of stressors in broiler chickens. Assessing animal welfare is necessary for animal behavior and product quality perspectives. Birds have a unique visual system, and their behavior is primarily mediated by vision. Different monochromatic light regimes can affect feed conversion ratio, modulating broiler chickens' systematic immune response and aggressive behavior. With the advancement of lighting technology, new possibilities have emerged to enhance traditional lighting programs in poultry houses. This review integrates recent findings on the use of monochromatic light and its impact on broilers' welfare, growth, and physiological response. [ABSTRACT FROM AUTHOR]

Lead (Pb), a heavy metal environmental pollutant, poses a threat to the health of humans and birds. Inflammation is one of the most common pathological phenomena in the case of illness and poisoning. However, the underlying mechanisms of inflammation remain unclear. The cerebellum and the thalamus are important parts of the nervous system. To date, there have been no reports of Pb inducing inflammation in animal cerebellums or thalami. Selenium (Se) can relieve Pb poisoning. Therefore, we aimed to explore the mechanism by which Se alleviates Pb toxicity to the cerebellums and thalami of chickens by establishing a chicken Pb or/and Se treatment model. Our results demonstrated that exposure to Pb caused inflammatory damage in cerebellums and thalami, evidenced by the characteristics of inflammation, the decrease in anti-inflammatory factors (interleukin (IL)-2 and interferon-γ (INF-γ)), and the increase in pro-inflammatory factors (IL-4, IL-6, IL-12β, IL-17, and nitric oxide (NO)). Moreover, we found that the IL-2/IL-17–NO pathway took part in Pb-caused inflammatory injury. The above findings were reversed by the supplementation of dietary Se, meaning that Se relieved inflammatory damage caused by Pb via the IL-2/IL-17–NO pathway. In addition, an up-regulated oxidative index malondialdehyde (MDA) and two down-regulated antioxidant indices (glutathione (GSH) and total antioxidant capacity (TAC)) were recorded after the chickens received Pb stimulation, indicating that excess Pb caused an oxidant/antioxidant imbalance and oxidative stress, and the oxidative stress mediated inflammatory damage via the GSH–IL-2 axis. Interestingly, exposure to Pb inhibited four glutathione peroxidase (GPx) family members (GPx1, GPx2, GPx3, and GPx4), three deiodinase (Dio) family members (Dio1, Dio2, and Dio3), and fifteen other selenoproteins (selenophosphate synthetase 2 (SPS2), selenoprotein (Sel)H, SelI, SelK, SelM, SelO, SelP1, SelPb, SelS, SelT, SelU, and selenoprotein (Sep)n1, Sepw1, Sepx1, and Sep15), suggesting that Pb reduced antioxidant capacity and resulted in oxidative stress involving the SPS2–GPx1–GSH pathway. Se supplementation, as expected, reversed the changes mentioned above, indicating that Se supplementation improved antioxidant capacity and mitigated oxidative stress in chickens. For the first time, we discovered that the SPS2–GPx1–GSH–IL-2/IL-17–NO pathway is involved in the complex inflammatory damage mechanism caused by Pb in chickens. In conclusion, this study demonstrated that Se relieved Pb-induced oxidative stress and inflammatory damage via the SPS2–GPx1–GSH–IL-2/IL-17–NO pathway in the chicken nervous system. This study offers novel insights into environmental pollutant-caused animal poisoning and provides a novel theoretical basis for the detoxification effect of Se against oxidative stress and inflammation caused by toxic pollutants. [ABSTRACT FROM AUTHOR]

Lead (Pb), a toxic environmental pollutant, is hazardous to the health of humans and birds. Bursa of Fabricius (BF) is a unique organ of birds. Toxic substances can attack BF and induce proteotoxicity. Increased heat shock proteins (HSPs) can induce oxidative damage. Selenium (Se) can alleviate harmful substance-caused oxidative damage. This study aimed to investigate whether Pb can cause oxidative damage and proteotoxicity, as well as Se reverse Pb-caused chicken BF toxicity. A model of chickens treated with Se and Pb alone and in combination was established. BFs were collected on days 30, 60, and 90. H&E and qRT-PCR were performed to observe the microstructure and to detect HSP27, HSP40, HSP60, HSP70, and HSP90 mRNA levels, respectively, in BFs. Multivariate correlation analysis and principal component analysis were conducted to explore the correlation among the five HSPs. In our results, Pb caused BF damage and up-regulated the five HSPs at three time points, causing oxidative damage and proteotoxicity via HSP27–HSP40–HSP70–HSP90 pathway. Furthermore, Pb caused time-dependent stress on HSP27, HSP40, HSP60, and HSP70. In addition, Se relieved Pb-caused damage and up-regulation of HSPs. Taken together, we concluded that Se alleviated Pb-caused oxidative injury and proteotoxicity in chicken BFs via the HSP27–HSP40–HSP70–HSP90 pathway. [ABSTRACT FROM AUTHOR]