Dietary supplementation with a microencapsulated complex of thymol, carvacrol, and cinnamaldehyde improves intestinal barrier function in weaning piglets

Abstract BACKGROUND The authors previously prepared a microencapsulated complex of thymol, carvacrol, and cinnamaldehyde (MEEO). This study aimed to evaluate the effect of MEEO on the intestinal mucosal barrier and homeostasis in weaning piglets. A comparison of the effect of MEEO versus chlortetracycline (CTC) was performed in this study. RESULTS Piglets were divided into three groups – control (Con), MEEO, and CTC groups – and raised for 28 days. The results showed that MEEO significantly elevated the ratio of the villus height and the crypt depth in the jejunum and decreased the crypt depth in the ileum compared with the other groups ( P < 0.05); it also upregulated the messenger ribonucleic acid (mRNA) expression of tight junction protein in the small intestine. Compared with the Con group, MEEO increased the concentration of secretory immunoglobulin A (sIgA), cathelicidin antimicrobial peptides (CAMP), and interleukin 10 (IL‐10), while decreasing the interleukin 1 beta (IL‐1 β ) concentration in both jejunal and ileal mucosa ( P < 0.05). The mRNA expression of jejunal mucosal MUC1 and ileal mucosal MUC2 was increased in the MEEO group compared with the other groups ( P < 0.05). Intestinal microbial analysis showed that dietary treatment had little impact on the ileal microbial structure. A significant rise in the genus Lactobacillus was, however, found in the MEEO group. There is a positive correlation between the Lactobacillus and sIgA, and between the Lactobacillus and CAMP, indicating that an improvement in the mucosal barrier function by the addition of MEEO may be associated with the proliferation of Lactobacillus. CONCLUSION Dietary supplementation with MEEO improves intestinal barrier function in weaning piglets, the effect of which was superior to CTC. © 2022 Society of Chemical Industry.