Gut complex carbohydrates and intestinal microflora in broiler chickens fed with oregano (Origanum vulgareL.) aqueous extract and vitamin E

Vitamin E Regulates the Collagen Contents in the Body Wall of Sea Cucumber (Apostichopus japonicus) via Its Antioxidant Effects and the TGF-β/Smads Pathway

A 70-day feeding experiment was performed to investigate the effects of dietary vitamin E at different addition levels (0, 100, 200, and 400 mg/kg) on the growth, collagen content, antioxidant capacity, and expressions of genes related to the transforming growth factor beta (TGF-β)/Sma- and Mad-related protein (SMAD) signaling pathway in sea cucumbers (Apostichopus japonicus). The results showed that the A. japonicus in the group with 200 mg/kg vitamin E exhibited significantly higher growth rates, hydroxyproline (Hyp) and type III collagen contents, and superoxide dismutase (SOD) activity, as well as the upregulation of genes related to Tenascin, SMAD1, and TGF-β. Additionally, the A. japonicus in the group with 100 mg/kg vitamin E exhibited significantly higher body-wall indexes, denser collagen arrangements, improved texture quality, higher activities of glutathione peroxidase (GSH-Px) and peroxidase (POD), as well as the upregulation of genes related to collagen type I alpha 2 chain (COL1A2), collagen type III alpha 1 chain (COL3A1), and Sp-Smad2/3 (SMAD2/3). In contrast, the A. japonicus in the group with 400 mg/kg vitamin E showed a decrease in the growth rates, reduced Hyp contents, increased type I collagen contents, collagen fiber aggregation and a harder texture, along with the downregulation of genes related to the TGF-β/SMAD signaling pathway. Furthermore, the A. japonicus in the group with 400 mg/kg exhibited oxidative stress, reflected by the lower activities of SOD, GSH-Px, and POD. These results indicated that A. japonicus fed diets with the addition of 100-200 mg/kg vitamin E had improved collagen retention and texture quality by increasing the activities of antioxidant enzymes and the expressions of genes in the TGF-β/SMAD signaling pathway. However, the excessive addition of vitamin E (400 mg/kg) induced oxidative stress, which could increase the collagen degradation and fibrosis and pose a threat to the growth and texture quality of A. japonicus.

Systematic review on microbiome-related nutritional interventions interfering with the colonization of foodborne pathogens in broiler gut to prevent contamination of poultry meat

This systematic review aimed to compile the available body of knowledge about microbiome-related nutritional interventions contributing to improve the chicken health and having an impact on the reduction of colonization by foodborne pathogens in the gut. Original research articles published between 2012 and 2022 were systematically searched in Scopus and PubMed. A total of 1,948 articles were retrieved and 140 fulfilled the inclusion criteria. Overall, 73 papers described 99 interventions against colonization by Escherichia coli and related organisms; 10 papers described 15 interventions against Campylobacter spp.; 36 papers described 54 interventions against Salmonella; 40 papers described 54 interventions against Clostridium perfringens. A total of 197 microbiome-related interventions were identified as effective against one or more of the listed pathogens and included probiotics (n = 80), prebiotics (n = 23), phytobiotics (n = 25), synbiotics (n = 12), organic acids (n = 12), enzymes (n = 4), essential oils (n = 14) and combination of these (n = 27). The identified interventions were mostly administered in the feed (173/197) or through oral gavage (11/197), in the drinking water (7/197), in ovo (2/197), intra amniotic (2/197), in fresh or reused litter (1/197) or both in the feed and water (1/197). The interventions enhanced the beneficial microbial communities in the broiler gut as Lactic acid bacteria, mostly Lactobacillus spp., or modulated multiple microbial populations. The mechanisms promoting the fighting against colonization by foodborne pathogens included competitive exclusion, production of short chain fatty acids, decrease of gut pH, restoration of the microbiome after dysbiosis events, promotion of a more stable microbial ecology, expression of genes improving the integrity of intestinal mucosa, enhancing of mucin production and improvement of host immune response. All the studies extracted from the literature described in vivo trials but performed on a limited number of animals under experimental settings. Moreover, they detailed the effect of the intervention on the chicken gut without details on further impact on poultry meat safety.

Dietary oregano aqueous extract improves growth performance and intestinal health of broilers through modulating gut microbial compositions

BACKGROUND

Intestinal health plays a pivotal role in broiler chicken growth. Oregano aqueous extract (OAE) effectively exerts anti-inflammatory and antibacterial effects. However, the protective effects of OAE on intestinal health in broilers and the underlying mechanism remain unclear. This study aimed to investigate the potential effects of OAE on growth performance, the gut microbiota and intestinal health. A total of 840 1-d-old male and female broilers (Arbor Acres) were randomly allocated into 6 groups as follows: basal diet (Con), Con + antibiotics (Anti, colistin sulfate 7 g/kg, roxarsone 35 g/kg), Con + 400, 500, 600 and 700 mg/kg OAE (OAE400, OAE500, OAE600 and OAE700). Subsequently, fermentation in vitro together with oral administration trials were carried out to further assess the function of OAE on intestinal health of broilers.

RESULTS

Dietary 700 mg/kg OAE supplementation resulted in an increase (P < 0.05) in body weight and a decrease (P < 0.05) in feed conversion ratio when compared with the control during d 22 to 42 of the trial. OAE addition resulted in lower (P < 0.05) jejunal crypt depth and mRNA expression of IL-4 and IL-10 at d 42. In addition, dietary OAE addition increased the abundance of Firmicutes (P = 0.087) and Lactobacillus (P < 0.05) in the cecum, and increased (P < 0.05) the content of acetic acid and butyric acid. In the in vitro fermentation test, OAE significantly increased (P < 0.05) the abundance of Lactobacillus, decreased (P < 0.05) the abundance of unspecified_Enterobacteriaceae, and increased the content of acetic acid (P < 0.05). In the oral administration trial, higher (P < 0.05) IL-4 expression was found in broilers when oral inoculation with oregano fermentation microorganisms at d 42. And SIgA content in the ileum was significantly increased (P = 0.073) when giving OAE fermentation supernatant.

CONCLUSIONS

Dietary OAE addition could maintain intestinal health and improve growth performance through enhancing intestinal mucosal immunity and barrier function mediated by gut microbiota changes.

Effects of Major Families of Modulators on Performances and Gastrointestinal Microbiota of Poultry, Pigs and Ruminants: A Systematic Approach

Considering the ban on the use of antibiotics as growth stimulators in the livestock industry, the use of microbiota modulators appears to be an alternative solution to improve animal performance. This review aims to describe the effect of different families of modulators on the gastrointestinal microbiota of poultry, pigs and ruminants and their consequences on host physiology. To this end, 65, 32 and 4 controlled trials or systematic reviews were selected from PubMed for poultry, pigs and ruminants, respectively. Microorganisms and their derivatives were the most studied modulator family in poultry, while in pigs, the micronutrient family was the most investigated. With only four controlled trials selected for ruminants, it was difficult to conclude on the modulators of interest for this species. For some modulators, most studies showed a beneficial effect on both the phenotype and the microbiota. This was the case for probiotics and plants in poultry and minerals and probiotics in pigs. These modulators seem to be a good way for improving animal performance.

Potency of Origanum vulgare and Andrographis paniculata extracts on growth performance in poultry

The objective of this study was to investigate the effect of phytobiotics combination of Origanum vulgare and Andrographis paniculata water extracts (FOA) mixed into the feed of broiler and specific-pathogen-free chickens as an alternative to Antibiotics Growth Promoter (AGP). Performance, intestinal bacteria characteristic, and oocysts of Eimeria spp. in feces were measured and compared with the AGP-added group. The first experiment in broiler chickens compared FOA, Zinc Bacitracin (ZB, as an AGP group), and negative control. On day 28, FOA group and ZB group showed significantly higher body weight than the control group (P < 0.05). The FCR of ZB group was better than FOA group. However, FOA group displayed better microbiota profile than ZB group and negative control, with more Lactobacillus spp. and Bacillus spp., and less Escherichia coli and Salmonella spp. isolated from intestines. The second experiment in specific-pathogen-free chickens showed the anticoccidial effect of FOA addition to reduce the number of oocysts per gram (OPG) from live coccidia vaccine. FOA group and Amprolium group showed OPG reduction (82.53% and 92.02%, respectively) after 7 days of treatment. In conclusion, the combination of Origanum vulgare and Andrographis paniculata extract can function as an AGP replacement in feed.

Medicinal Plants for Prophylaxis and Therapy of Common Infectious Diseases In Poultry-A Systematic Review of In Vivo Studies

Medicinal plants for prophylaxis and therapy of common infectious diseases in poultry have been studied for several years. The goal of this review was to systematically identify plant species and evaluate their potential in prophylaxis and therapy of common diseases in poultry caused by bacteria and gastrointestinal protozoa. The procedure followed the recommendations of the PRISMA statement and the AMSTAR measurement tool. The PICOS scheme was used to design the research questions. Two databases were consulted, and publications were manually selected, according to predefined in- and exclusion criteria. A scoring system was established to evaluate the remaining publications. Initially, 4197 identified publications were found, and 77 publications remained after manual sorting, including 38 publications with 70 experiments on bacterial infections and 39 publications with 78 experiments on gastrointestinal protozoa. In total, 83 plant species from 42 families were identified. Asteraceae and Lamiaceae were the most frequently found families with Artemisia annua being the most frequently found plant, followed by Origanum vulgare. As compared to placebo and positive or negative control groups, antimicrobial effects were found in 46 experiments, prebiotic effects in 19 experiments, and antiprotozoal effects in 47 experiments. In summary, a total of 274 positive effects predominated over 241 zero effects and 37 negative effects. Data indicate that O. vulgare, Coriandrum sativum, A. annua, and Bidens pilosa are promising plant species for prophylaxis and therapy of bacterial and protozoal diseases in poultry.

Plant Feed Additives as Natural Alternatives to the Use of Synthetic Antioxidant Vitamins on Poultry Performances, Health, and Oxidative Status: A Review of the Literature in the Last 20 Years

Plant feed additives (PFA) such as essential oils, extracts, and by-products from plant processing can be included in poultry diets. A total of 39 peer-reviewed articles were selected from the literature published in the last 20 years (2000–2020) comparing PFA antioxidant effects with synthetic antioxidant vitamins (mainly vitamin E) in poultry nutrition. The PFA can be used as an effective nutritional strategy to face poultry’s oxidative stress with positive impact also on their productivity and efficiency. They can partially or completely replace antioxidant synthetic vitamins (the latter administered at doses between 150 and 500 mg/kg) in animal diets, sometimes affecting important physiological functions or expressing synergistic effect with the synthetic antioxidants. It is crucial to take into consideration the issues related to the absorption and the metabolism of these additives and their interaction with gut microbiota. However, some form- and dose-dependent negative effects on growth performances are observed.

Effects of Maternal and Progeny Dietary Vitamin E on Growth Performance and Antioxidant Status of Progeny Chicks before and after Egg Storage

Simple Summary

Prolonged egg storage duration has been indicated to decrease the quality of hatchlings and the growth performance of offspring. Maternal nutrition plays a vital role in growth of chicks post-hatch. However, no work has been performed to evaluate whether or not maternal nutrition could improve the growth performance of offspring hatched from stored eggs. Here, we aimed to investigate the effects of maternal and progeny dietary vitamin E supplementation on the growth performance and antioxidant status of offspring before and after egg storage. Our results showed that maternal dietary vitamin E (VE) supplementation of 200 or 400 mg/kg could improve the growth performance and antioxidant status of offspring hatched from stored eggs, but not for that of offspring hatched from unstored eggs. These findings suggested that maternal dietary vitamin E was beneficial to improve the quality of long-term storage eggs.

Abstract

Two trials were conducted to investigate the effects of maternal and progeny dietary vitamin E (VE) supplementation on the growth performance and antioxidant status of offspring before and after egg storage. A total of 576 75-week-old Ross 308 breeder hens were assigned to three dietary VE treatments (100, 200, and 400 mg/kg) with 6 replicates of 32 hens for 12 weeks. Two trials were conducted with offspring hatched from eggs laid at weeks 9 and 12 of breeder feeding trial, respectively. Trial 1 was conducted by a 3 × 2 factorial arrangement of treatments with three levels of maternal dietary VE (100, 200, and 400 mg/kg) and two levels of progeny dietary VE (0 and 35 mg/kg). Trial 2 was conducted with three maternal dietary VE treatment (100, 200, and 400 mg/kg), and chicks were hatched from eggs stored for 14 d and received the same progeny diet with no addition of VE. Results showed that in trial 1, maternal (100, 200, and 400 mg/kg) and progeny (0 and 35 mg/kg) dietary VE supplementation did not affect the growth performance of offspring hatched from unstored eggs (p > 0.05). In trial 2, in the case of long-term egg storage, maternal dietary VE supplementation of 200 and 400 mg/kg increased the body weight (BW) of 21- and 42-d-old offspring and the body weight gain (BWG) of offspring from 1 to 21 d (p < 0.05), and decreased the feed conversion ratio (FCR) of offspring from 1 to 21 d (p < 0.05) compared to 100 mg/kg VE. As the maternal dietary VE levels increased, the liver and serum antioxidant status of offspring enhanced (p < 0.05). In conclusion, maternal dietary VE supplementation of 200 or 400 mg/kg could improve the growth performance and anti-oxidant status of offspring hatched from stored eggs, but not for that of offspring hatched from unstored eggs. The suitable VE level for the broiler breeder diet was 400 mg/kg in the case of long-term egg storage.

Effects of dietary Origanum vulgare on gilthead seabream (Sparus aurata L.) immune and antioxidant status

Origanum sp. is a very common genus of aromatic plants worldwide distributed around the Mediterranean area and O. vulgare (oregano) is the most important species of this genus throughout the world. Due the known medicinal properties of oregano, the effect of diets enriched with 0% (control), 0.5% and 1% oregano leaves powder was studied on the growth, immune and antioxidant status of gilthead seabream (Sparus aurata L.). Fish fed with oregano 0.5% and 1% enriched diets improved both humoral (IgM and bactericidal activity in skin mucus and protease activity in serum) and cellular (head kidney leucocytes phagocytic ability) immunity at 15 and 30 days. Furthermore, the addition of oregano did not provoke any significant effect neither in the growth promotion nor in the liver antioxidant enzymes activity studied in the serum and skin mucus. The possibility of using O. vulgare as a functional additive to fish diet is discussed.

Immuno- and glyco-histochemistry as a tool to evaluate the oregano supplemented feed effects in pig gut

Among oregano properties, its antioxidant and antibacterial effects are particularly interesting. Oregano is also able to induce a higher glycoconjugate production in gut, creating a physical barrier against microorganisms. This study evaluated the effects of adding an aqueous extract of oregano (OAE) to the diet of two homogenous groups of pigs during the finisher phase. The diets were as follows: control commercial diet (CTR group) and CTR diet supplemented (2 g/kg) with OAE (O group). Samples of ileum and caecum from the two groups were examined by conventional histochemistry to analyze complex carbohydrates and by immunohistochemistry to detect Bcl-2 Associate X protein (BAX), an indicator of oxidative stress. Glyco-histochemistry showed significant differences between the two groups. Immunohistochemistry revealed a lower presence of BAX in O group. The OAE supplementation improved the production of glycoconjugates, able to enhance in pig the protection of intestinal mucosa by means of direct and indirect defense actions. The reduced BAX immunostaining observed in O group may be an indicator of enhanced antioxidant action promoted by oregano. The results of this study can be used in further research to identify ways to improve endogenous defence ability, with the aim of reducing antibiotic use and preventing antimicrobial resistance.

Oregano Feed Supplementation Affects Glycoconjugates Production in Swine Gut

Simple Summary

The European ban towards antibiotics is increasing the number of studies on the effects of feed additives, such as plant extracts, in order to enhance the health and welfare status of domestic animals intended for human consumption. Origanum vulgare possesses multiple pharmacological characteristics and its antioxidant and antibacterial properties are particularly interesting. Besides, a recent study aimed at evaluating the effects of oregano aqueous extract supplementation in poultry nutrition gave encouraging results regarding the secretion of glycoconjugates in the gut which increases tissue hydration and protects the intestinal mucosa from pathogenic bacteria, viruses, and parasites. Therefore, we investigated the effects of oregano feed supplementation on antioxidant and defense ability of pig gut. Our results showed that there was improved production of glycoconjugates in the duodenum and colon of pigs fed with supplementation of oregano aqueous extract, enhancing protection of the mucosa of these sections of the intestine. Also, we observed an enhanced antioxidant action in the two examined gut tract samples of the group supplemented with oregano. Findings can be used in further research to identify ways to improve endogenous defense ability with to reduce antibiotic use and prevent antimicrobial resistance.

Abstract

This study evaluated the effects of adding oregano aqueous extract (OAE) to the diet of pig slaughtered at finisher stage. Study was performed to identify glycoconjugates and evaluate the oxidative stress levels in the duodenum and colon intestinal tracts. Glycohistochemistry was performed by staining with Periodic acid–Schiff (PAS), Alcian blue (AB) pH 2.5, AB-PAS, AB pH 1, AB pH 0.5, low iron diamine, and high iron diamine. Serial sections were pre-treated with sialidase V before staining with AB pH 2.5 (Sial-AB) preceded or not by saponification. To study oxidative stress, an immunohistochemical analysis was applied to investigate the presence of the oxidative stress target molecule Bcl-2 Associate X protein (BAX). Findings show that oregano aqueous extract supplementation improves the production of the secretion glycoconjugates involved in direct and indirect defense, thus enhancing the protection of the pig intestinal mucosa. Moreover, the reduced BAX protein immunostaining observed in both duodenum and colon of swine of the oregano-supplemented group respect to that observed in the control group suggests an enhanced antioxidant action by oregano adding. Findings could be useful for other studies aiming to reduce antibiotic use and prevent antimicrobial resistance.

Apelin system detection in the reproductive apparatus of ewes grazing on semi-natural pasture

Apelin (APLN) is an adipokine with pleiotropic effects involved in the regulation of metabolic, cardiovascular, immune, and electrolyte balance function. Recent studies demonstrated a pivotal role in the regulation of male and female reproduction. APLN and its receptor (APLNR) were found in the hypothalamic-pituitary-gonad axis tissues, regulating gonadotropin release and steroidogenesis. However, to date, there are no studies that describe APLN system in the reproductive apparatus of the sheep. The study was performed on 10 Comisana x Appenninica adult dry ewes reared in a semi-natural pasture. Organ samples were collected from five animals in the two pasture functional phases: after maximum pasture flowering (Group 1) and after maximum pasture dryness (Group 2). Experiments were devised to characterize the gene expression and protein localization of the APLN/APLNR system in ewe reproductive apparatus; in addition, the concentration of plasma APLN was evaluated during the trial. Through immunohistochemical analysis, a positive staining for APLN was observed in the large luteal cells, in the epithelial cell coat of the ampulla, in the uterus epithelial lining and in the uterine glands. APLNR was observed in the granulosa cells, in the large luteal cells, in the secreting cells of the ampulla, in the uterus epithelial lining and uterine glands. The transcripts for APLN and APLNR were evidenced in all organ tissues examined. The highest level of APLN mRNA was detected in the Group 2 ewes in the luteal phase of the ovarian cycle compared to Group 1 ewes in the anestrous one. The relative content of APLN transcript was respectively twofold higher in the ovary (P < 0.05) and uterus (P < 0.05) and threefold higher in the ampulla (P < 0.05) in the Group 2 vs Group 1. The same trend of APLN transcript was evaluated for APLNR mRNA in uterus (P < 0.05) and ovary (P < 0.05). No difference was evidenced between Group 1 and Group 2 for APLNR mRNA levels. The plasma APLN level was fairly constant during the trial period. In conclusion, the present data suggest that the apelinergic system is involved in the reproduction function of ewes, being differentially distributed and expressed in the organs of the reproductive apparatus of ewes; these variations could be related to the sexual cycle and to the cyclic activity of the reproductive apparatus.

Dietary leonurine hydrochloride supplementation attenuates lipopolysaccharide challenge-induced intestinal inflammation and barrier dysfunction by inhibiting the NF-κB/MAPK signaling pathway in broilers

This study was performed to evaluate the beneficial effects of dietary leonurine hydrochloride (LH) supplementation on intestinal morphology and barrier integrity and further illuminate its underlying antioxidant and immunomodulatory mechanisms in lipopolysaccharide (LPS)-treated broilers. A total of 120 1-d-old male broilers (Ross 308) were assigned to 4 treatment groups with 6 replicates of 5 birds per cage. The experiment was designed in a 2 × 2 factorial arrangement with LH (0 or 120 mg/kg) and LPS (injection of saline or 1.5 mg/kg body weight) as treatments. On days 14, 16, 18, and 20 of the trial, broilers were intraperitoneally injected with LPS or physiological saline. Compared with the control group, LPS-challenged broilers showed impaired growth performance (P < 0.05) from day 15 to day 21 of the trial, increased serum diamine oxidase (DAO) and D-lactic acid (D-LA) levels coupled with reduced glutathione (GSH) content and total superoxide dismutase (T-SOD) activity (duodenal and jejunal mucosa), reduced malondialdehyde (MDA) content (duodenal, jejunal, and ileal mucosa), and compromised morphological structure of the duodenum and jejunum. Additionally, LPS challenge increased (P < 0.05) the mRNA expression of proinflammatory cytokine genes and reduced tight junction (TJ) protein expression in the jejunum. However, dietary LH prevented LPS-induced reductions in average daily gain (ADG) and average daily feed intake (ADFI) in broilers. It also alleviated LPS challenge-induced increases in serum DAO levels, MDA content (duodenal and jejunal mucosa), and jejunal crypt depth (P < 0.05) but reduced villus height, GSH content (jejunal mucosa), and T-SOD activity (duodenal and jejunal mucosa) (P < 0.05). Additionally, LH supplementation significantly downregulated the mRNA expression of nuclear factor (NF)-κB, cyclooxygenase-2 (COX-2), and proinflammatory cytokines (TNF-α, IL-1β, and IL-6) and upregulated the mRNA expression of zonula occludens-1 (ZO-1) and Occludin in the jejunal mucosa induced by LPS (P < 0.05). On the other hand, LH administration prevented LPS-induced activation of the p38, extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) mitogen-activated protein kinases (MAPKs) and attenuated IkB alpha (IκBα) phosphorylation and nuclear translocation of NF-κB (p65) in the jejunal mucosa. In conclusion, dietary LH supplementation attenuates intestinal mucosal disruption mainly by accelerating the expression of TJ proteins and inhibiting activation of the NF-κB/MAPK signaling pathway.

Effects of orange essential oil on intestinal microflora in mice

BACKGROUND

The intestinal microbiota has a wide variety of functions in the host. A positive effect of plant extract on intestinal microbiota in animals has been reported. However, the effect of orange essential oil and its components limonene, linalool and citral on intestinal microflora in mice has seldom been reported. The effects of intragastric administration of orange essential oil and limonene, linalool and citral on intestinal microflora and biochemical indexes in mice were studied.

RESULTS

The effect of essential oil, linalool and citral on immune organ index (spleen and thymus index), IgM and IL-2 was not significant (P > 0.05). A significant increase (P < 0.05) of H⁺ K⁺ -ATPase activity, IgA, IgG, and IL-2 in the limonene group was observed when compared with the control group. Orange essential oil, limonene, linalool and citral could significantly reduce the content of short-chain fatty acids in the cecum and colon of mice. Principal coordinates analysis showed that intestinal bacterial structure of limonene group cecum and colon was apparently separated from other groups. The relative abundance of Lactobacillus in cecum and colon in essential oil, limonene, linalool and citral groups was higher than that in the control group.

CONCLUSIONS

Orange essential oil and limonene, linalool and citral could affect the intestinal microflora of mice, and enhance the relative abundance of Lactobacillus. The intestinal bacterial structure of cecum and colon in the limonene group was quite different from other groups. This indicated a more obvious effect of limonene on intestinal bacteria, also resulting in significant changes in blood immune index and short-chain fatty acids in mice. © 2019 Society of Chemical Industry.

Gene co-expression networks in liver and muscle transcriptome reveal sex-specific gene expression in lambs fed with a mix of essential oils

BACKGROUND

Essential oil (EO) dietary supplementation is a new strategy to improve animal health. EO compounds have antiparasitic, antimicrobial, antiviral, antimycotic, antioxidant and anti-inflammatory proprieties. Nutrigenomics investigations represent innovative approaches in understanding the relation between diet effect and gene expression related to the animal performance. Few nutrigenomics studies have used a high-throughput RNA-Sequencing (RNA-Seq) approach, despite great potential of RNA-Seq data in gene expression quantification and in co-expression network analyses. Our aim is to use the potential of RNA-Sequencing data in order to evaluate the effect of an EO supplementary diet on gene expression in both lamb liver and muscle.

RESULTS

Using a treatment and sex interaction model, 13 and 4 differentially expressed genes were identified in liver and muscle respectively. Sex-specific differentially expressed (DE) genes were identified in both sexes. Using network based analysis, different clusters of co-expressed genes that were highly correlated to the diet were detected in males vs. females, in agreement with DE analysis. A total of five regulatory genes in liver tissue associated to EO diet were identified: DNAJB9, MANF, UFM1, CTNNLA1 and NFX1. Our study reveals a sex-dependent effect of EO diet in both tissues, and an influence on the expression of genes mainly involved in immune, inflammatory and stress pathway.

CONCLUSION

Our analysis suggests a sex-dependent effect of the EO dietary supplementation on the expression profile of both liver and muscle tissues. We hypothesize that the presence of EOs could have beneficial effects on wellness of male lamb and further analyses are needed to understand the biological mechanisms behind the different effect of EO metabolites based on sex. Using lamb as a model for nutrigenomics studies, it could be interesting to investigate the effects of EO diets in other species and in humans.