The objective of this study was to investigate the effect of encapsulated essential oils and organic acids (EOA) on the growth performance, egg quality, intestinal morphology and functions, and microbial count of laying hens from week 21 to 30. A total of five hundred and four 21-wk-old layers were randomly allotted into 4 groups consisting of 7 replicates with 18 birds per replicate. The birds were fed a basic diet (CON) or diets with EOA at 150 mg/kg, 300 mg/kg, and 450 mg/kg in the other 3 groups, respectively. Compared to the CON group, the addition of 150 mg/kg EOA significantly increased laying rate (P < 0.05) of hens from week 21 to 25. A linear increasing (linear, P < 0.01) in ileal villus height of laying hens fed EOA from 150 to 300 mg/kg was observed at week 30. At week 25, the supplementation of 300 mg/kg EOA significantly increased (P < 0.05) mRNA relative expression of aminopeptidase, sodium-glucose cotransporter 1, and Na+-independent neutral amino acid transporter in duodenum and glucose transporter 2 in jejunum of laying hens compared to the CON groups. Meanwhile, the relative expression of glucose transporter 2 mRNA in the jejunum was upregulated with increasing concentration of EOA in diets (linear, P < 0.05). Hens in EOA 300 group had higher mRNA relative expression of mucin-2 in ileum (P < 0.05) than hens in CON group. Additionally, the secretory immunoglobulin in ileum A were linear decreased (linear, P < 0.01) with the increasing supplement of EOA. Dietary supplementation with EOA tended to increase (P = 0.083) the counts of Bifidobacterium in cecal digesta at week 25 and 30. In conclusion, dietary with EOA may maintain intestinal tract morphology and promote digestive and absorptive capacities and barrier function, especially at 300 mg/kg. This study provided evidence of using EOA as a potential feed additive for laying hens.

中文翻译：

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包封精油和有机酸对蛋鸡产蛋早期产蛋性能、蛋品质、肠道形态、屏障功能和微生物群落数量的影响。

本研究的目的是研究封装的精油和有机酸 (EOA) 对 21 至 30 周的蛋鸡生长性能、蛋品质、肠道形态和功能以及微生物数量的影响。总共 500将 4 个 21 周龄的蛋鸡随机分成 4 组，每组 7 个重复，每个重复 18 只鸡。在其他 3 组中，这些鸟分别被饲喂基本饮食 (CON) 或含有 150 mg/kg、300 mg/kg 和 450 mg/kg 的 EOA 饮食。与 CON 组相比，添加 150 mg/kg EOA 从第 21 周到第 25 周显着提高了母鸡的产蛋率（P < 0.05）。饲喂 EOA 的蛋鸡回肠绒毛高度呈线性增加（线性，P < 0.01）在第 30 周观察到 150 至 300 mg/kg。在第 25 周，与 CON 相比，添加 300 mg/kg EOA 显着增加（P < 0.05）蛋鸡十二指肠中氨基肽酶、钠-葡萄糖协同转运蛋白 1 和 Na+非依赖性中性氨基酸转运蛋白和空肠中葡萄糖转运蛋白 2 的 mRNA 相对表达量（P < 0.05）团体。同时，随着日粮中EOA浓度的增加，空肠中葡萄糖转运蛋白2 mRNA的相对表达上调（线性，P < 0.05）。EOA 300组母鸡回肠黏蛋白2的mRNA相对表达高于CON组（P < 0.05）。此外，随着EOA的增加，回肠A中分泌的免疫球蛋白呈线性下降（线性，P <0.01）。在第 25 周和第 30 周，添加 EOA 的膳食补充剂倾向于增加（P = 0.083）盲肠食糜中双歧杆菌的数量。总之，含有 EOA 的膳食可维持肠道形态并促进消化和吸收能力以及屏障功能，尤其是在 300 mg/kg 时。该研究提供了使用 EOA 作为蛋鸡潜在饲料添加剂的证据。