Abstract The study was conducted to evaluate the effects of increasing inclusion levels of the mixture of Bacillus subtilis and essential oils (BSEO) on production, hatching performance, egg quality, serum antioxidant capacity, immune response, and hormone levels of laying hens. A total of 768 24-wk-old layers were randomly allotted into 4 treatments with 6 replicates of 32 birds each replicate. The experiment lasted for 84 d, and the birds were fed a basal diet (CON) or diets with BSEO at 300 (BSEO-1), 600 (BSEO-2), and 900 mg/kg (BSEO-3) in the other 3 groups, respectively. As the BSEO level increased, egg production (linear, p < .05), yolk index (linear, p < .01), glutathione peroxidase activity (linear, p < .01), total antioxidant capacity (linear, p < .01), oestradiol level (linear, p < .01), the value luteinizing hormone/follicle-stimulating hormone (linear, p < .05) increased in a linear manner. Hatchability (linear and quadratic, p < .01), hatchability of fertile of eggs (linear and quadratic, p < .05), avian influenza virus antibody level (linear, p < .01; quadratic, p < .05), parathyroid hormone level (linear and quadratic, p < .01) in the serum increased linearly and quadratically. Taken together, dietary with BSEO in laying hens could significantly improve egg production, hatchability, and hatchability of fertile eggs, which were associated with an enhancement of antioxidant capacity and the level of AIV-Ab in the serum. This study provided evidence of using BSEO as a potential feed additive for laying hens. Highlights Dietary supplementation of BSEO decreased the feed conversion ratio and eggshell thickness of laying hens. Dietary supplementation of BSEO improved the egg weight, fertility, hatchability, hatchability of fertile eggs, and yolk index of laying hens. Dietary supplementation of BSEO enhanced the antioxidant capacity and the level of AIV-Ab in the serum.

中文翻译：

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使用包封的枯草芽孢杆菌和精油改善血液的抗氧化和免疫状态以及蛋鸡的生产和孵化性能

摘要 本研究旨在评估增加枯草芽孢杆菌和精油 (BSEO) 混合物的添加水平对蛋鸡的生产、孵化性能、蛋质量、血清抗氧化能力、免疫反应和激素水平的影响。总共768个24周龄的蛋鸡被随机分配到4个处理中，6个重复，每个重复32只鸡。实验持续 84 天，鸡只饲喂基础日粮 (CON) 或 BSEO 为 300 (BSEO-1)、600 (BSEO-2) 和 900 mg/kg (BSEO-3) 的日粮。分别3组。随着 BSEO 水平的增加，产蛋量（线性，p < .05）、蛋黄指数（线性，p < .01）、谷胱甘肽过氧化物酶活性（线性，p < .01）、总抗氧化能力（线性，p < .01） )，雌二醇水平（线性，p < .01），促黄体激素/促卵泡激素值（线性，p < .05）以线性方式增加。孵化率（线性和二次方，p < .01），受精蛋孵化率（线性和二次方，p < .05），禽流感病毒抗体水平（线性，p < .01；二次方，p < .05），甲状旁腺血清中的激素水平（线性和二次方，p < .01）呈线性和二次方增加。总之，蛋鸡日粮中添加 BSEO 可以显着提高产蛋率、孵化率和受精蛋的孵化率，这与抗氧化能力和血清中 AIV-Ab 水平的增强有关。该研究提供了使用 BSEO 作为蛋鸡的潜在饲料添加剂的证据。亮点 日粮中添加 BSEO 降低了蛋鸡的饲料转化率和蛋壳厚度。日粮中添加 BSEO 提高了蛋鸡的蛋重、繁殖力、孵化率、受精蛋的孵化率和蛋黄指数。膳食补充剂 BSEO 增强了抗氧化能力和血清中 AIV-Ab 的水平。