ABSTRACT

1. Plant extracts and oils are supplemented in diets for chickens due to their antimicrobial capacities; however, little information exists whether they influence intestinal motility and barrier function.

2. The present study aimed to determine the effect of increasing levels of cinnamon bark oil (CBO; 0%, 0.038%, 0.076% and 0.151%) and coconut oil emulsions prepared with soy and sunflower lecithin on the contractile function of enteric wall muscles in the jejunum and ileum and jejunal barrier function in laying hens.

3. For testing muscle contraction, mid-jejunal and ileal segments (n = 4 each per hen) from four laying hens were placed in a longitudinal orientation into isolated organ baths filled with Krebs buffer and fastened to force transducers. Muscle segments were induced to contract with acetylcholine and the effects of the oil emulsions on contraction were measured.

4. For barrier function, distal jejunal pieces were stripped of serosa before mounting into Ussing chambers and recording changes in short-circuit current (I_SC) and transepithelial tissue conductivity (G_T) before and after addition of the respective emulsion.

5. The CBO decreased the muscle tone, representing a relaxation of on average 36.2% and 42.6% for the jejunum and ileum, respectively, compared to before the addition (P < 0.001). Moreover, CBO linearly decreased the I_SC and G_T of the jejunal mucosa, indicating a greater absorption of anions and increased barrier function (P < 0.001). Only the coconut oil-sunflower lecithin emulsion relaxed the muscles, whereas both coconut oil-lecithin emulsions increased the I_SC but reduced the G_T of the jejunal mucosa, which suggested an increased cation absorption and decreased paracellular permeability, respectively (P < 0.05).

6. In conclusion, CBO and coconut oil-lecithin emulsions showed the potential to increase jejunal barrier function, whereas CBO may be more efficacious to slow down digesta passage in the small intestine.

摘要

1.由于鸡的抗菌能力强，因此在鸡的日粮中补充了植物提取物和油脂；然而，关于它们是否影响肠蠕动和屏障功能的信息很少。

2.本研究旨在确定用大豆和葵花卵磷脂制备的肉桂皮油（CBO； 0％，0.038％，0.076％和0.151％）和椰子油乳液的含量增加对肠壁肌肉收缩功能的影响在空肠和回肠以及空肠中产蛋鸡的屏障功能。

3.为了测试肌肉收缩，将四只产蛋母鸡的空肠和回肠中段（每只母鸡n = 4）纵向放置在装有Krebs缓冲液的独立器官浴中，并固定以迫使换能器。诱导肌肉节段与乙酰胆碱收缩，并测量油乳剂对收缩的影响。

4.为了屏障功能，在安装到使用室中之前将空肠远端的浆膜剥离，并记录在添加相应乳剂之前和之后的短路电流（I _SC）和跨上皮组织电导率（G _T）的变化。

5. CBO降低了肌肉张力，与添加前相比，空肠和回肠的平均松弛分别为36.2％和42.6％（P <0.001）。此外，CBO线性降低了空肠黏膜的I _SC和G _T，表明阴离子吸收更大，屏障功能增强（P <0.001）。只有椰子油-葵花卵磷脂乳剂使肌肉放松，而两种椰子油-卵磷脂乳剂均增加了空肠黏膜的I _SC但降低了空肠黏膜的G _T，这分别表明增加了阳离子吸收和降低了细胞旁通透性（P <0.05） 。

6.总之，CBO和椰子油-卵磷脂乳液显示出增加空肠屏障功能的潜力，而CBO可能更有效地减缓小肠消化道的通过。