College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China.
College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi, 712100, P.R. China.
Poult Sci. 2019 Dec 1;98(12):6751-6760. doi: 10.3382/ps/pez391.
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.
本研究旨在探讨包被精油和有机酸（EOA）对 21 至 30 周龄产蛋鸡生长性能、蛋品质、肠道形态和功能以及微生物数量的影响。将 504 只 21 周龄蛋鸡随机分为 4 组，每组 7 个重复，每个重复 18 只鸡。鸡群分别饲喂基础日粮（CON）或添加 150、300 和 450 mg/kg EOA 的日粮。与 CON 组相比，从第 21 周到第 25 周，添加 150 mg/kg EOA 显著提高了母鸡的产蛋率（P<0.05）。在第 30 周，随着 EOA 添加量从 150 至 300 mg/kg 的线性增加（线性，P<0.01），产蛋鸡的回肠绒毛高度也随之增加。在第 25 周，与 CON 组相比，添加 300 mg/kg EOA 显著提高（P<0.05）了十二指肠中肠碱性氨基酸肽酶、钠-葡萄糖协同转运蛋白 1 和非依赖钠的中性氨基酸转运体以及空肠葡萄糖转运体 2 的 mRNA 相对表达水平。同时，随着日粮中 EOA 浓度的增加，空肠葡萄糖转运体 2 mRNA 的相对表达水平呈线性上调（线性，P<0.05）。与 CON 组相比，添加 300 mg/kg EOA 的母鸡回肠中黏蛋白-2 的 mRNA 相对表达水平更高（P<0.05）。此外，回肠分泌型免疫球蛋白 A 呈线性下降（线性，P<0.01），随着 EOA 添加量的增加而下降。在第 25 和 30 周，日粮中添加 EOA 可使盲肠内容物中双歧杆菌的数量呈线性增加（线性，P<0.01）。综上所述，日粮中添加 EOA 可能维持肠道形态，促进消化吸收能力和屏障功能，尤其是在 300 mg/kg 时效果更为显著。本研究为 EOA 作为潜在的蛋鸡饲料添加剂提供了依据。
