Oregano essential oil showed limited effects on pigs' carcass quality and haematology whereas a transcriptome analysis revealed significant modulations in the jejunum and the ileum

Abstract

Pig production depends on a health and performance balance. An approach to improve intestinal health is the oregano essential oil (OEO) supplementation within a conventional diet. Intestinal integrity regulating effects, for example gene expression, of some feed ingredients are important key factors for that balance. We hypothesized that OEO affects the expression of genes associated with pigs’ intestinal integrity. In four trials, a total of 86 pigs have been used. From weaning, the ‘treated’ group (n = 42) was additionally fed an oregano flavour additive [1500 mg/kg (7.5% pure OEO)] within the basal diet. The ‘control’ group (n = 44) was kept under identical environmental conditions, except the OEO. At age of 6 months, pigs were slaughtered with an average weight of 111.1 ± 10.9 kg. In addition to automatically generated ‘Fat‐o‐Meter’ (AutoFOM) data, carcass quality factors have been measured manually. Valuable cuts of meat, such as ham and belly, were significantly reduced in the OEO group. Effects of OEO on pigs' haematologic parameters were very limited. For transcriptome analysis, the most interesting microarray expression results have been listed in a table (topTable). Selected genes were technically validated by qPCR. As a result, few significant differences in animal development and meat quality have been found between the OEO treated and the control group. Depending on OEO supplementation, we found 93 differently regulated genes in the jejunal tissue (70 up, 23 down) and 60 in the ileal tissue (48 up, 12 down). Just three genes (GRIN3B [glutamate ionotropic receptor NMDA type subunit 3B], TJP1/ZO‐1 [tight junction protein ZO‐1] and one uncharacterized gene) were affected by OEO both in jejunum and ileum. qPCR validation revealed AKT serine/threonine kinase 3 (AKT3), Interferon (IFN) ‐ε, ‐ω, tight junction protein (TJP1)/ZO‐1 (ZO‐1) to be upregulated in the jejunum and C‐C motif chemokine ligand 21 (CCL21) was upregulated in the ileum of pigs that were supplemented with OEO. OEO supplementation had limited effects on pigs’ performance traits. However, we were able to demonstrate that OEO alters the expression of genes associated with adaptive immune response in pigs’ small intestine. These findings help to explain OEOs’ beneficial impact on pigs’ intestinal integrity.

Effects of dietary essential oil supplementation on growth performance, carcass yield, meat quality, and intestinal tight junctions of broilers with or without Eimeria challenge

“…Oregano oil supplementation upregulated the mRNA expression of intestinal barrier gene ZO-1 and Claudin-1 in the duodenum and Claudin-1 in the ileum of Eimeria -challenged broilers, which was consistent with the findings from Ruan et al (2021) . The upregulation of tight junction in the epithelial barrier was also reported in colorectal cancer mice model ( Leong et al, 2022 ), female pigs ( Hofmann et al, 2022 ), Escherichia coli -challenged mice ( Zhao et al, 2022 ), and colitis mice ( Raka et al, 2023 ). It is remarkable how essential oil interacts with the monolayer of enterocytes, probably due to their antioxidant capacity ( Toschi et al, 2022 ).…”

Identification of candidate genomic regions for thermogelled egg yolk traits based on a genome-wide association study

“…PTBP1 (polypyrimidine tract binding protein 1) is an RNA-binding protein, a specific inhibitor of mRNA splicing in the mammalian nervous system ( Medina et al, 2011 ). CFD promotes adipocyte differentiation and promotes adipogenesis ( Song et al, 2016 ), and GRIN3B affects beef quality ( Hofmann et al, 2022 ).…”

Alternatives to antibiotics in pig production: looking through the lens of immunophysiology

“…In addition to improve serum antibody reaction, tea tree oil is shown to increases liver IL-10 and decreases the IL-1β and TNF-α concentrations (Wang et al 2021b ). Hofmann et al ( 2022 ) have demonstrated that oregano essential oil can increase expressions of TJP1 (encoding tight junction protein ZO-1), Akt3, interferon signaling and CCL21 in the porcine small intestine (Hofmann et al 2022 ). Capsicum oleoresin or turmeric oleoresin supplement up-regulates the gene signature of immune activation ( C1QA, C5, CCL25, CD46, CFB, and FCN2 ), cell membrane integrity, and tight junctions in the porcine ileum mucosa; while garlic extract increases the expression of genes involved in fatty acid biosynthesis, defense response, and oxidation reduction in pigs (Liu et al 2014c ).…”