The Effect of an Essential Oil Blend on Growth Performance, Intestinal Health, and Microbiota in Early-Weaned Piglets

Abstract

Essential oils (EO) are promising feed additives for their antibacterial, antioxidant, and immune-enhancing abilities with low toxicity. Carvacrol, thymol, and cinnamaldehyde are commonly used to synthesize EO. However, few studies focus on combining these three EO in early-weaned piglets. In the present study, 24 piglets weaned at 21 d of age were randomly divided into 2 groups (6 replicate pens per group, 2 piglets per pen). The piglets were fed a basal diet (the control group) and a basal diet supplemented with 400 mg/kg EO (a blend consisting of carvacrol, thymol, and cinnamaldehyde, the EO group) for 28 days. At the end of the experiment, one piglet per pen was randomly chosen to be sacrificed. Growth performance, hematology, plasma biochemical indices, antioxidant capacity, intestinal epithelial development and immunity, colonic volatile fatty acids (VFA), and microbiota were determined. The results indicated that the diet supplemented with EO significantly improved average daily feed intake (ADFI, p < 0.01) and average daily gain (ADG, p < 0.05) in the day 0 to 28 period. EO supplementation led to a significant decrease in plasma lysozyme (p < 0.05) and cortisol levels (p < 0.01). Additionally, EO significantly promoted jejunal goblet cells in the villus, jejunal mucosa ZO-1 mRNA expression, ileal villus height, and ileal villus height/crypt depth ratio in piglets (p < 0.05). The ileal mucosal TLR4 and NFκB p-p65/p65 protein expression were significantly inhibited in the EO group (p < 0.05). Colonic digesta microbiota analysis revealed that bacteria involving the Erysipelotrichaceae family, Holdemanella genus, Phascolarctobacterium genus, and Vibrio genus were enriched in the EO group. In conclusion, these findings indicate that the EO blend improves ADG and ADFI in the day 0 to 28 period, as well as intestinal epithelial development and intestinal immunity in early-weaned piglets, which provides a theoretical basis for the combined use of EO in weaned piglets.

Effects of the Supplementation of Essential Oil Mixtures on Growth Performance, Nutrient Digestibility, Immune Status and Microbial Community in Weaned Piglets

“…However, no significant difference or trend was observed in the later stage of this animal trial across all groups regarding the content of short-chain fatty acids. In previous studies, dietary supplementation with 400 mg/kg essential oil mixtures (carvacrol, thymol and cinnamaldehyde) had no significant effects on volatile fatty acid concentrations in colon of piglets, and analysis of microbial α-diversity and β-diversity showed little difference [49]. In this study, although short-chain fatty acids concentrations were not affected, microbial diversity was changed.…”

Responses of intestinal morphology, immunity, antioxidant status and cecal microbiota to the mixture of glycerol monolaurate and cinnamaldehyde in laying hens

“… Kong et al (2023) reported that GML had a protective effect on intestinal morphology by improving the VH of the small intestine in challenged chicken embryos. Shao et al (2023) reported that the essential oil containing 13.8% cinnamaldehyde can significantly increase the VH and the VH/CD in the ileum of piglets, thus promoting the development of intestinal epithelium. In the current study, it was observed that the combination of GML and cinnamaldehyde in the diet of laying hens significantly increased the VH, the VH/CD of small intestine, and the duodenal villus area, decreased the duodenal and jejunal CD, and thus improved the digestibility and absorption rate of feed.…”

Essential oils in pig production: an alternative approach to health and welfare

“…However, a study by Kroismayr and co-workers [58,59] showed a tendency for essential oils to reduce villus length in the jejunum and ileum, whereas other previous reports showed no change in pigs [81]. The effects of dietary supplementation with a mixture of EOs, including thyme oil, were investigated in weaned piglets [82]. The study reported that piglets receiving the EO blend had improved growth performance.…”

“…The study reported that piglets receiving the EO blend had improved growth performance. This may be related to the beneficial effects of thyme EO on the gut environment, nutrient absorption and general health [82].…”