Effects of zinc methionine and selenium yeast on growth performance, antioxidant capacity, immune function and intestinal morphology of broiler chickens under heat stress

1. This study evaluated the effects of zinc methionine (Zn-met) and selenium (Se) yeast on growth performance, antioxidant capacity, immune function and intestinal morphology of broiler chickens under heat stress (HS).2. A total of 54, yellow-feather male broilers (35-d old) were randomly allocated to one of three groups; a control group (CON) fed a basal diet and maintained at 26 ± 1°C, a group fed the basal diet with cyclic HS alone or + Zn-met + Se yeast group (HZS) fed a basal diet supplemented with 250 mg/kg Zn-met and 150 mg/kg Se yeast. After the 7-d prep-trial period, the birds in the HS and the HZS groups were exposed to cyclic HS treatment (30 ± 1 to 34 ± 1°C) from d 8 for 2 weeks.3. The HS treated birds had reduced body weight, daily gain, feed intake and feed conversion ratio (p < 0.01) and increased mortality and rectal temperature, whereas the HZS group had a lower mortality rate and rectal temperature. The HS group had higher blood triglyceride (p < 0.01) and lower potassium (0.05) levels than the CON group. Exposure to HS increased the lipopolysaccharide levels (p < 0.05) and decreased the levels of immunoglobulin (Ig) A and IgG (p < 0.05), which were improved in the HZS group. The HZS group reversed the increase in blood catalase activity caused by heat stress and increased glutathione peroxidase levels (p < 0.05). Heat stress decreased villus height in the duodenum and jejunum, increased the crypt depth and decreased the villus height to crypt depth ratio in the small intestine, which were improved in the HZS group (p < 0.05).4. Dietary supplementation with Zn-met and Se yeast was shown to be an effective nutritional regulation strategy for alleviating any negative effects of heat stress in broiler performance.

The potential of pomegranate peel supplementation in Yellow-feathered broilers: effects on growth performance, serum biochemistry, antioxidant capacity, intestinal health, intestinal microbiota, and duodenal mucosal metabolites

This study aimed to investigate the effects of dietary supplementation with pomegranate peel powder (PP) on the growth performance, serum biochemistry, antioxidant capacity, intestinal microbiota, and duodenal mucosal metabolites of yellow-feathered broilers. A total of 360 yellow-feathered broilers were randomly divided into three groups, with their diets supplemented with different levels of PP (0, 1, and 4 g/kg) for 42 days. Dietary supplementation with PP significantly increased the average body weight and average daily gain of yellow-feathered broilers during the periods of 1-21 and 22-42 days, while reducing the feed conversion ratio (p < 0.05). It also decreased the serum levels of aspartate aminotransferase, alanine aminotransferase, creatinine, and uric acid, increased the activities of glutathione peroxidase and superoxide dismutase, and reduced malondialdehyde content in the serum, liver, and intestinal mucosa (p < 0.05). Furthermore, PP supplementation promoted the mRNA expression of farnesoid X receptor, peroxisome proliferator-activated receptor alpha, fatty acid-binding protein 4, epidermal growth factor/epidermal growth factor receptor, and B-cell lymphoma 2, while decreasing the mRNA expression of caspase-1 and interleukin-1 beta (p < 0.05). Regarding mucosal metabolites, PP supplementation increased the contents of polyunsaturated fatty acids (cis-11-eicosenoic acid, cis-13,16-docosadienoic acid, and cis-11,14-eicosadienoic acid), prostaglandin E2/G2, and secondary bile acids (apocholic, hyodeoxycholic, 7-ketodeoxycholic, and omega-muricholic acids) in the mucosa (p < 0.05). In terms of cecal microbiota, PP supplementation increased the β-diversity index (p < 0.05), elevated the relative abundances of Bacteroidota, Alistipes, Bacilli, and Actinobacteriota, and reduced the relative abundances of Clostridia and Gammaproteobacteria (p < 0.05). In conclusion, dietary supplementation of PP can improve intestinal health and growth performance of yellow-feathered broilers by regulating the composition of the gut microbiota.

Green tea polyphenol epigallocatechin-3-gallate mediates an antioxidant response via Nrf2 pathway in heat-stressed poultry: A review

Heat stress is a critical challenge in the poultry industry. It arises when birds are exposed to elevated ambient temperatures beyond their thermoneutral zone, often exacerbated by high humidity and inadequate ventilation. This condition disrupts the birds' ability to maintain thermal homeostasis, leading to physiological and behavioral changes such as increased panting, reduced feed intake, and elevated water consumption. These responses aim to dissipate heat but often result in energy imbalances, oxidative stress, and impaired immune function. Green tea polyphenols (GTPs) mitigate heat stress in poultry birds by modulating oxidative stress pathways, primarily by scavenging reactive oxygen species (ROS) and enhancing antioxidant defense mechanisms. These pathways play a pivotal role in neutralizing ROS generated during oxidative stress, inflammation, and exposure to electrophilic compounds. This action helps restore cellular balance and enhances overall antioxidant defense mechanisms by converting harmful free radicals into less reactive molecules, such as water and oxygen. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) plays a significant character in the activation of the enzymatic antioxidants network. It translocates to the nucleus upon activation, binds to antioxidant response elements (AREs) in the promoter regions of target genes, and upregulates the expression of key antioxidant enzymes. Therefore, the regulation of Nrf2 is considered a critical molecular marker in mitigating the effects of heat stress, as its activation enhances the expression of antioxidant and detoxification enzymes, protecting against oxidative damage and inflammation induced by elevated temperatures. This exploratory review summarizes the antioxidant mechanisms and anti-oxidative stress effects of GTPs in mitigating heat stress in poultry. It highlights the cytoprotective molecular basis of epigallocatechin-3-gallate (EGCG), particularly its role in modulating Nrf2-mediated cellular pathways, which enhance antioxidant defense systems and protect against oxidative damage.

Epigallocatechin Gallate Alleviates Lipopolysaccharide-Induced Intestinal Inflammation in Wenchang Chicken by Inhibiting the TLR4/MyD88/NF-κB Signaling Pathway

Intestinal inflammation significantly compromises broiler health and adversely affects growth performance. Epigallocatechin gallate (EGCG) was found to maintain the gut health of animals. However, the role and mechanism of EGCG in preventing lipopolysaccharide (LPS)-induced intestinal inflammation in chicks have not yet been fully elucidated. In the 35-day study, 140 one-day-old Wenchang chickens were randomly assigned to four treatments: CON (basal diet), LPS (basal diet + 1 mg/kg body weight (BW) LPS), L-EGCG (basal diet + 40 mg/kg BW EGCG + 1 mg/kg BW LPS), and H-EGCG (basal diet + 60 mg/kg BW EGCG + 1 mg/kg BW LPS). On days 31, 33, and 35 of age, broilers in the LPS, L-EGCG, and H-EGCG treatments received intraperitoneal injections of LPS. The LPS reduced jejunal villus height, villus height/crypt depth ratio, Claudin1 mRNA, catalase (CAT) activity, and interleukin-10 (IL-10) levels compared to CON while elevating diamine oxidase (DAO), interleukin-1β (IL-1β), and tumor necrosis factor α (TNF-α). EGCG improved growth performance in LPS-challenged broilers, elevating jejunal villus height and Claudin1/ZO-1 mRNA with reduced serum DAO. It enhanced antioxidant capacity via increased serum total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD), CAT, glutathione peroxidase (GSH-Px) activities, and a decreased malondialdehyde (MDA) concentration. Concurrently, EGCG lowered IL-1β/TNF-α and raised IL-10 in serum/jejunum. Crucially, EGCG suppressed jejunal TLR4/MyD88/NF-κB mRNA and protein expression under LPS. These findings demonstrate EGCG's protective role against LPS-induced intestinal inflammation in Wenchang chickens through TLR4/MyD88/NF-κB pathway inhibition.

Exploring the Link Between Mucin 2 and Weaning Stress-Related Diarrhoea in Piglets

To explore the relationship between intestinal mucin 2 (MUC2) and weaning-induced diarrhoea in piglets, we analysed Min and Landrace piglets. The piglets were divided into a healthy weaned group, a weaned diarrhoea group, and a healthy unweaned control group. Intestinal tissues were collected, and goblet cell numbers, sizes, and degrees of intestinal injury were observed and recorded. Intestinal tissue MUC2 mRNA and protein expression were analysed via quantitative real-time PCR (qRT-PCR) and Western blotting. Min pigs presented significantly lower diarrhoea rates and intestinal injury scores than Landrace pigs (p < 0.01). The intestinal injury scores in the weaned diarrhoea group were significantly greater than those in the unweaned groups (p < 0.05), with Min pigs consistently exhibiting lower injury scores than Landrace pigs. Specifically, unweaned Min pigs presented significantly greater duodenal MUC2 mRNA (p < 0.05), and weaned healthy Min pigs presented notably greater expression in both the duodenum and jejunum (p < 0.01). These findings reveal enhanced intestinal protection against weaning stress and diarrhoea in Min pigs, with elevated MUC2 levels likely contributing to lower injury scores and milder symptoms, thus highlighting the influence of genetic differences.

EGCG Alleviates Skeletal Muscle Oxidative Damage in Heat-Stressed Pigs via Keap1/PGAM5 Complex-Mediated Mitophagy

The heat stress (HS) induced by high temperatures can result in oxidative damage to muscles, thereby compromising both muscle growth and immune function within the organism. Mitophagy serves as a pivotal pathway in alleviating excessive ROS production and subsequent oxidative damage. However, the potential role of epigallocatechin-3-gallate (EGCG), a natural antioxidant found in tea, in mitophagy under HS remains unexplored. Here, we present evidence of EGCG mitigating the oxidative-redox imbalance in porcine skeletal muscles induced by HS involving the antioxidant enzyme system mediated by the Keap1/Nrf2 pathway and mitophagy mediated by the PINK1/Parkin pathway. Importantly, we identified phosphate mutase 5 (PGAM5) for the first time as a key protein modulated by EGCG under HS conditions, regulating mitophagy. Inhibition of PGAM5 significantly attenuated the activation of mitophagy by EGCG. Molecular docking and dynamics simulations further suggested that EGCG directly binds to Keap1, disrupting the Keap1-PGAM5 protein interaction and thus promoting the release of PGAM5 and subsequently activating mitophagy. In summary, this study represents the first discovery of EGCG directly targeting Keap1/PGAM5-mediated mitophagy, which serves as a potential functional supplement for regulating the antioxidant capacity in pigs.

Synergistic impact of Salmonella typhimurium and Eimeria spp. coinfection on turkey poults: Growth performance, salmonella colonization, and ceca microbiota insights

Salmonella contamination in poultry products is a significant concern due to its potential to cause severe economic losses and public health problems. On the other side, coccidiosis is induced by Eimeria (E.) species. involves the destruction of host intestinal epithelial cells and subsequent invasion of pathogens, resulting in performance reduction and enhanced pathogen infection in poultry and economic losses for the poultry industry. A study was conducted to evaluate the impact of Eimeria infection and Salmonella typhimurium (ST) on growth performance, Salmonella colonization, and ceca microbiota in turkey poult. A total of 420 one-day-old male turkey poults were randomly allocated into six treatments, with five replicated cages for each treatment, over a 21-day experimental period. The study followed a 2 × 3 factorial design. Treatments consisted of NC, negative control without any challenge; T1, challenged with 8000 oocysts of E. meleagrimitis and E. adenoeides at d 8; T2, challenged with 16,000 oocysts of E. meleagrimitis and E. adenoeides at d 8; T3, challenged with nalidixic acid-resistant Salmonella typhimurium (ST) at d 0; T4, challenged with ST at d 0 and 8000 oocysts of E. meleagrimitis and E. adenoeides at d 8; T5, challenged with ST at d 0 and 16,000 oocysts of E. meleagrimitis and E. adenoeides at d 8. The Eimeria challenge groups significantly reduced the BW compared to the non-challenge group (P < 0.001). The challenged groups decreased FI during 9-14 days of age (P < 0.01). Salmonella typhimurium did not affect BW entire trial period (P > 0.05). Gut permeability (GP) increased in the challenge groups compared to the NC group (P < 0.001). Both ST and Eimeria significantly decreased superoxide dismutase (SOD) in the liver (P < 0.01). The challenge groups had lower villus height (VH) and higher crypt depth (CD) compared to the NC group, resulting in decreased VH:CD ratio in the duodenum and jejunum (P < 0.01). The groups T1, T2, and T4 had significantly higher fat deposition than the NC group (P < 0.05). The coinfected groups (T4 and T5) had higher salmonella colonization in the spleen compared to the ST-infected group (T3, P < 0.05). The ST challenge significantly decreased alpha diversity, including pielou evenness and Shannon entropy (P < 0.05). The Proteobacteria phylum and Enterobacteriaceae family significantly increased in T5 compared to the NC, T1, T2, and T3 (P < 0.05). In conclusion, Eimeria infection negatively impacted growth, gut health, intestine barrier integrity, and histology, while Salmonella had a milder effect on performance. Coinfection with Salmonella and Eimeria spp. led to changes in gut microbiota and increased liver Salmonella colonization and fat deposition in turkey poults.

Substituting ethoxyquin with tea polyphenols and propyl gallate enhanced feed oxidative stability, broiler hepatic antioxidant capacity and gut health

The safety of ethoxyquin has garnered increasing attention. This study evaluated the effects of partially substituting ethoxyquin with tea polyphenols and propyl gallate on feed oxidative stability, hepatic antioxidant properties, intestinal morphology and barrier functions, as well as the antioxidant and anti-inflammatory profiles of the intestinal mucosa in broilers. A total of 351 one-day-old male Arbor Acres Plus broilers were randomly assigned to 3 groups, each comprising 9 replicates with 13 birds per replicate. The treatments included a control group (CON) fed a basal diet, an ethoxyquin group (EQ) that received the basal diet supplemented with 120 g/t of ethoxyquin, and a substitution group (TP) receiving the basal diet supplemented with 6 g/t of tea polyphenols, 6 g/t of propyl gallate, and 30 g/t of ethoxyquin. In vitro experiments showed that both EQ and TP supplementation significantly reduced the acid value (AV), peroxide value (POV), and total oxidation value (TOV) of the feeds, with the TP group exhibiting lower AV and TOV than the EQ group. In vivo assessments revealed no significant differences in growth performance among the groups. Additionally, the TP group exhibited significantly higher glutathione peroxidase activity, increased glutathione content, and elevated protein expression of Keap1, Nrf2, and NQO1 in the liver compared to the control group (P < 0.05). Moreover, dietary TP significantly increased liver catalase activity, glutathione content, and NQO1 protein levels compared to the EQ group (P < 0.05). Both additives effectively reduced malondialdehyde levels in the intestinal mucosa by approximately 50% (P < 0.05) through the activation of the Nrf2/ARE pathway, as indicated by increased mRNA expression of TXN, CAT, GPX1, and GPX4 (P < 0.05). Furthermore, compared to the control group, the TP group exhibited greater villus height and villus height-to-crypt depth ratio (VCR) in the jejunum, as well as elevated VCR in the ileum (P < 0.05). The TP group also achieved the lowest serum levels of diamine oxidase activity, D-lactate and lipopolysaccharide contents among all groups (P < 0.05). The inclusion of both EQ and TP increased the mRNA expression of Occludin, Claudin-1, Mucin-2, and E-cadherin in the jejunum (P < 0.05). Moreover, the combination of tea polyphenols and propyl gallate effectively mitigated the proinflammatory effect of ethoxyquin, as evidenced by reductions in TNF-α, IL-18, and IFN-γ expression, potentially mediated by inhibition of the TLR-4/MyD88/NF-κB signaling pathway. In conclusion, this study demonstrates that partially replacing ethoxyquin with tea polyphenols and propyl gallate enhances feed oxidative stability, liver antioxidant capacity, and gut health in broilers, suggesting an efficient alternative with a lower dosage requirement.

Assessment of the Impact of Dietary Supplementation with Epigallocatechin Gallate (EGCG) on Antioxidant Status, Immune Response, and Intestinal Microbiota in Post-Weaning Rabbits

This study was conducted to investigate the impact of EGCG on antioxidant stress, immune response, and intestinal microbiota flora in post-weaning rabbits. A total of 144 40 d Ira rabbits (equally divided by sex), were randomly allocated to six treatments. with five groups receiving doses of 200, 400, 600, 800, and 1000 mg/kg of EGCG, while one group served as a control without EGCG. Over 48 days, this study the assessed growth performance, antioxidant capacity, immune system, intestinal morphology, and cecal microbiota in the rabbits. The results showed that EGCG did not affect growth performance; however, significant linear and quadratic correlations were observed between the MDA, T-AOC, and GSH-Px activities in the liver and jejunum (p < 0.05). Quadratic effects were observed for the spleen and thymus indexes and serum IgG levels with increasing EGCG dosages (p < 0.05). Additionally, positive linear and quadratic effects were found on the ileal villus height and the villus height/crypt depth ratio. The relative abundances of Euryarchaeota, Patescibacteria, and Synergistota were significantly enriched in rabbits fed with high dosages (600-1000 mg/kg) of EGCG. Conclusively, the addition of large doses of EGCG (400-800 mg/kg) can effectively suppress oxidative stress and alleviate weaning stress, thereby contributing to the protection of post-weaning rabbits.

Potential benefits of advanced chelate-based trace minerals in improving bone mineralization, antioxidant status, immunity, and gene expression modulation in heat-stressed broilers

Organic sources of trace minerals (TM) in broiler diets are more bioavailable and stable than inorganic sources, making them particularly beneficial during challenging periods such as heat stress (HS) conditions. A 42-d study investigated the effects of using advanced chelate technology-based TM (ACTM) or adding varying amounts of ACTM to broiler diets during HS conditions. The study involved 672 male broiler chickens in 7 treatment groups, including a thermoneutral control (TNC) group and six HS treatments. There were 8 replicate pens per treatment and 12 birds per replicate. The six HS treatments included birds exposed to a cyclic HS environment (34°C) for 8 h and were as follows: HSC, which consisted of the same basal diet with the recommended ITM levels; ACTM50 and ACTM100, which replaced the basal diet with 50% and 100% ACTM instead of ITM; ITM+ACTM12.5 and ITM+ACTM25, which involved adding extra ACTM to the ITM basal diet at 12.5% and 25%, respectively; and ITM125, which used 125% of the recommended levels of ITM in the basal diet. Compared with the HSC treatment, the TNC, ACTM100, and ITM+ACTM25 treatments resulted in increased (P < 0.05) body weight; tibia weight; tibia ash, phosphorus, iron, and manganese contents; secondary antibody titers; and serum TAC and SOD values but decreased (P < 0.05) serum MDA concentrations and the expression levels of the hepatic genes IL-1β, IL-6, and INF-γ. The TNC and ACTM100 groups also showed greater (P < 0.05) feed efficiency, tibia length, tibia zinc content, and hepatic SOD1 expression but exhibited reduced (P < 0.05) hepatic NF-kB expression. Significant increases (P < 0.05) in primary anti-NDV titers, serum GPx1 activity, and Nrf2 and GPx1 gene expression levels were also detected in the ACTM100, ITM+ACTM12.5, and ITM+ACTM25 groups. In conclusion, the findings suggest that replacing ITM with ACTM or adding ACTM to ITM diets, especially at a 25% higher dose, can effectively protect broilers from heat stress by promoting growth, reducing inflammation, and increasing the expression of antioxidant proteins.

Dietary curcumin supplementation attenuates hepatic damage and function abnormality in a chronic corticosterone-induced stress model in broilers

Chronic stress refers to the activation of the hypothalamic-pituitary-adrenal (HPA) axis and elevated blood contents of ACTH and corticosterone (CORT), exhibiting significant adverse effects on health outcomes. Currently, natural polyphenol compounds are increasingly being explored as potential therapeutic agents and have been considered as a treatment option for a variety of stress-induced diseases. Curcumin (CUR) is the main substance in Curcuma longa (Zingiberacea) rhizome that has strong health-beneficial properties. The study aimed to assess the potential protective effects of CUR on hepatic oxidative stress damage and abnormal lipid deposition in a chronic CORT-induced stress (CCIS) model in broilers. One hundred and twenty experimental broilers were randomly divided into 1) control group (CON), 2) CUR group (200 mg/kg feed), 3) CORT group (4 mg/kg BW CORT) and 4) CORT+CUR group (200 mg/kg feed plus 4 mg/kg BW CORT). The liver histology, glycolipid metabolism and oxidative stress were determined. In addition, qPCR was performed to identify shifts in genes expression. Compared with CON group, broilers under CCIS showed a decreased body weight, body weight gain and average daily gain, while dietary CUR significantly reversed these adverse effects. Furthermore, the plasma contents of TCH, TG, HDL-C, LDL-C, TP, GLB and AST were all significantly increased in CCIS broilers, while dietary CUR obviously alleviated the increase of TCH, HDL-C, LDL-C and AST, and relieved the hepatic lipid deposition disorder and liver injury. Moreover, CCIS significantly increased the contents of MDA in both liver and plasma, and decreased the content of plasma SOD, while CUR obviously reversed these changes, showing reduced oxidative stress damage. Finally, the mRNA expressions of FAS, ACC, SCD and the protein level of PPAR-γ were significantly increased, meanwhile the mRNA expression of lipolytic genes ACOX1, ATGL and CPT as well as two major intracellular antioxidant enzymes SOD1 and GPX1 were obviously decreased, while CUR effectively reversed these effects. These results showed that dietary CUR effectively alleviated CCIS-induced body weight loss, hepatic oxidative damage and lipid deposition disorder, suggesting the possible therapeutic effectiveness of CUR against hepatic damage and function abnormality caused by CCIS.

Potassium diformate affects the growth and development of broilers by improving intestinal function and digestive enzyme activity

Gut health of broiler chickens is essential for production performance. The present study aimed to evaluate the impact of dietary supplementation with potassium diformate (KDF) on growth performance and intestinal health in broiler chickens. A total of 180 Arbor Acres (AA) broiler chickens were randomly allocated into 3 treatments, with 6 replicates, containing 10 chicks in each replicate. The treatment groups were: control group (CON) was fed a basal diet; KDF-4 groups fed the basal diet with 4 g/kg KDF; KDF-8 groups fed the basal diet with 8 g/kg KDF. The experiment period lasted for 42 d. During the starter phase, the ADFI and F/G of broilers in KDF groups were lower (P < 0.05) compared to the CON group. Furthermore, the BW and ADG in KDF-4 group was improved (P<0.05). The treatment groups exhibited a significant increase (P < 0.05) in both ADG and ADFI during the grower and overall phase. Moreover, the F/G in KDF-4 group was lower (P < 0.05) compared to the CON and KDF-8 groups. The semi-eviscerated weight rate (SEWR), eviscerated carcass weight rate (ECWR), pectoral muscle rate (PMR), and leg muscle rate (LMR) of broilers were improved (P < 0.05) in KDF groups. The serum levels of glucose (GLU) and UREA (UA) were significantly higher (P < 0.05) in KDF-8 group. Additionally, the nutrient apparent utilization rate of dry matter (DM), energy (EE), and crude protein (CP) were improved (P < 0.05) in KDF-4 group. The villus height (VH) and villus height to crypt depth ratio (V/C) of duodenum, jejunum, and ileum were higher (P < 0.05) in KDF groups compared to the CON group, while crypt depth (CD) was significantly reduced (P < 0.05). The digestive enzyme activities of lipase (LIP), amylase (AMS), or trypsin (TPS) were significantly enhanced (P < 0.05) in the intestinal chyme, while the total bacterial count, Escherichia coli, Lactobacilli, Bifidobacteria, and Bacillus were reduced (P < 0.05) in the ileum. This study demonstrates that the inclusion of KDF in the diet of broilers leads to improvements in growth, slaughter performance, nutrient utilization rate, and maintenance of intestinal health.

Dietary Organic Zinc Supplementation Modifies the Oxidative Genes via RORγ and Epigenetic Regulations in the Ileum of Broiler Chickens Exposed to High-Temperature Stress

Heat stress (HS) is a significant concern in broiler chickens, which is vital for global meat supply in the dynamic field of poultry farming. The impact of heat stress on the ileum and its influence on the redox homeostatic genes in chickens remains unclear. We hypothesized that adding zinc to the feed of heat-stressed broilers would improve their resilience to heat stress. However, this study aimed to explore the effects of organic zinc supplementation under HS conditions on broiler chickens' intestinal histology and regulation of HS index genes. In this study, 512 Xueshan chickens were divided into four groups: vehicle, HS, 60 mg/kg zinc, and HS + 60 mg/kg zinc groups. Findings revealed that zinc supply positively increased the VH and VH: CD in the ileum of the broilers compared to the HS group, while CD and VW decreased in Zn and HS+Zn supplemented broilers. Zn administration significantly increased superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and decreased the enzymatic activities of reactive oxygen species (ROS) and malondialdehyde (MDA) compared to the HS group. In addition, Zn administration significantly increased relative ATP, complex I, III, and V enzyme activity compared to the HS group. Furthermore, the expression of acyl-CoA synthetase long-chain family member 4 (ACSL4), lactate transporter 3 (LPCAT3), peroxiredoxin (PRX), and transferrin receptor (TFRC) in the protein levels was extremely downregulated in HS+Zn compared to the HS group. Zn supply significantly decreased the enrichment of RORγ, P300, and SRC1 at target loci of ACSL4, LPCAT3, and PRX compared to the HS group. The occupancies of histone active marks H3K9ac, H3K18ac, H3K27ac, H3K4me1, and H3K18bhb at the locus of ACSL4 and LPCAT3 were significantly decreased in HS+Zn compared to the HS group. Moreover, H3K9la and H3K18la at the locus of ACSL4 and LPCAT3 were significantly decreased in HS+Zn compared to the HS group. This study emphasizes that organic Zn is a potential strategy for modulating the oxidative genes ACSL4, LPCAT3, PRX, and TFRC in the ileum of chickens via nuclear receptor RORγ regulation and histone modifications.

Effects of essential oils on heat-stressed poultry: A review

While certain animal species are sensitive to heat stress, poultry particularly modern breeds, are more susceptible to high ambient temperatures. This has major implications for the poultry industry, as heat stress causes large financial losses. These economic losses will probably increase as a consequence of a predicted rise in global temperatures. Heat stress adversely affects various aspects of poultry, including physiological responses, growth and production performance, meat quality, egg quality, and reproductive activities. These effects occur through specific molecular and metabolic pathways. To mitigate the impacts of heat stress, it is crucial to go beyond administrative practices and implement dietary interventions during high ambient temperature. Such interventions aim to optimize the development of stressed bird species in terms of performance, health, and profitability. Essential oils have shown promising in mitigating the negative effects of heat stress and improved antioxidant status, growth and yield performance, as well as meat and egg quality in poultry. They actively participate in certain metabolic and molecular pathways that help to counteract the effects of heat stress. The article discusses the impacts of essential oil supplementation on the relationships between antioxidant enzyme activity, these molecular, and metabolic pathways, as well as various parameters such as growth and yield performance, and product quality heat-stressed poultry.

Epigallocatechin gallate modification of physicochemical, structural and functional properties of egg yolk granules

The aim of this study was to prepare protein-polyphenol covalent complexes by treating egg yolk granules (EYG) with alkali in the presence of epigallocatechin gallate (EGCG) and characterize the physicochemical, structural, and functional properties of these covalent complexes. Results revealed that the optimal covalent binding occurred when the concentration of EGCG reached 0.15% (w/w), resulting in a grafting rate of 1.51 ± 0.03%. As the amount of EGCG increased, corresponding increases were observed in the particle size and ζ-potential of the complexes, thereby enhancing their stability. Furthermore, our analysis using fluorescence spectroscopy, FTIR, SEM, and SDS-PAGE collectively demonstrated the formation of a covalent complex between EYG and EGCG. Notably, the covalent complexes exhibited improved antioxidant activity and emulsifying properties. Overall, this study establishes a theoretical framework for the future practical application of EYG, emphasizing the potential of EGCG to modify its structural and functional characteristics.

Effects of Sex on Growth Performance, Carcass Traits, Blood Biochemical Parameters, and Meat Quality of XueShan Chickens

The demand for high-quality chilled chicken has continued to increase in China. Chickens are sexually dimorphic, and to better understand the specific differences in chicken production based on sex, we examined how sex affects growth performance, carcass traits, and meat quality of yellow-feathered chickens. Male and female Xueshan chickens were used as the experimental model. Although males exhibited better growth performance, including body weight (BW), body slope, keel, shank length, and shank girth (p < 0.05), as well as carcass traits, such as dressed weight, leg muscle, and lean meat, females had higher carcass and breast muscle yields (p < 0.05). Males had higher follicle density and yellowness (b*) of the skin and better skin than females (p < 0.05). Among blood biochemical parameters, the serum content of corticosterone (CORT) was higher in males, while those of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), total antioxidant capacity (T-AOC), and catalase (CAT) were lower in males than in females (p < 0.05). The pH levels, shear force, and moisture content quality were better in male breast meat, while the intramuscular fat content (IMF) was lower in males than in females (p < 0.05). The redness (a*) and moisture content were higher in male leg meat, while the pH, water-loss rate (WLR), lightness (L*), and IMF were lower (p < 0.05). The muscle fiber diameter and cross-sectional area were also higher in males (p < 0.05). Consumers felt that soup of male chicken was better than female (p < 0.05), while mouthfeel and tenderness acceptance of breast meat were different between the sexes. These results indicate that female chickens can be marketed as a whole carcass, while males are more suitable for processed carcass products. This study provides significant insights into the production and processing methodologies of yellow-feathered chickens.

Protective influence of supplementary betaine against heat stress by regulating intestinal oxidative status and microbiota composition in broiler chickens

To assess the impact of supplementing betaine (BT) under heat stress (HS) conditions on broiler performance and intestinal health from 21 to 42 days of age, a total of 150 male Ross 308 broilers were indiscriminately allotted to 3 treatments with 10 replications of 5 birds each. The control (CON) group was given a basal ration and accommodated at a thermoneutral condition (22 ± 1 °C), whereas the HS and HS + BT groups were raised under cyclic HS (33 ± 1 °C for 8 h and 22 ± 1 °C for 16 h per day) and received the basal ration without or with 1000 mg/kg BT, respectively. The HS reduced average daily gain (ADG); average daily feed intake; villus height (VH); VH to crypt depth (CD) ratio (VCR); activities of trypsin, lipase, glutathione peroxidase (GPX), and catalase; and enumeration of Lactobacillus and Bifidobacterium (P < 0.05) and augmented feed conversion ratio (FCR), CD, malondialdehyde (MDA) accumulation, and enumeration of Escherichia coli, Clostridium, and coliforms (P < 0.05). Conversely, BT supplementation heightened ADG, VH, VCR, trypsin activity, GPX activity, and populations of Lactobacillus and Bifidobacterium (P < 0.05) and lowered FCR, MDA accumulation, and Clostridium population (P < 0.05). Furthermore, the FCR value, trypsin and GPX activities, MDA content, and Bifidobacterium and Clostridium populations in the HS + BT group were nearly equivalent to those in the CON group. To conclude, feeding BT under HS conditions could improve broiler performance through improving intestinal health by specifically mitigating oxidative damage and enhancing the colonization of beneficial bacteria.

Effect of tea polyphenols supplement on growth performance, antioxidation, and gut microbiota in squabs

Early life nutritional supplementation can significantly improve pigeon health. Both the nutritional crops of parental pigeons and the intestinal development of squabs play key roles in the growth rate of squabs. Tea polyphenols (TPs), as natural plant extracts, exhibit potential biological activities. However, the impact of TPs on the intestinal function of squabs is not known. This study evaluated the effects of TPs on growth performance, immunity, antioxidation, and intestinal function in squabs. A total of 432 young pigeons (1 day old) were divided into four groups: a control group (fed a basic diet) and three treatment groups (low, medium, and high dose groups; 100, 200, and 400 mg/kg TPs, respectively). On the 28th day, samples of serum, mucosal tissue, and digests from the ileum of squabs were collected for analysis. The results revealed that TP supplementation significantly reduced the feed-to-meat ratio and improved the feed utilization rate and serum biochemical indices in squabs. Additionally, it enhanced the intestinal barrier function of birds by promoting intestinal development and integrity of tight junctions and regulating digestive enzyme activities and intestinal flora. Mechanistically, TPs activated the Nrf2-ARE signaling pathway, which may be associated with improved antioxidant and immune responses, correlating with an increased abundance of Candida arthritis and Corynebacterium in the ileum.

Effects of dietary supplementation of cumin (Cuminum cyminum L.) essential oil on expression of genes related to antioxidant, apoptosis, detoxification, and heat shock mechanism in heat-stressed broiler chickens

This study was carried out to evaluate the impact of cumin essential oil (CEO) supplementation on levels of certain gene expression related to antioxidant, apoptotic, detoxific, and heat shock mechanisms in the breast meat and ileum of heat-stressed broilers. The study was conducted on a 2 × 6 factorial design (heat stress + feed additive) on 600 day-old male broiler chicks for a period of 42 days. From day 7 to 42, although broilers in heat stress groups (HT) were exposed to constant chronic heat stress (36 °C), others were housed at thermoneutral ambient temperature (TN). The chicks in both conditions were fed with 6 experimental diets: C0 (basal diet with no additive), ANTIB (basal diet + 100 mg/kg chloramphenicol), VITE (basal diet + 50 IU α-tocopherol), C2 (basal diet + 200 mg/kg CEO), C4 (basal diet + 400 mg/kg CEO), C6 (basal diet+ 600 mg/kg CEO). The results showed that heat stress upregulated (except for Bcl-2) the genes related to antioxidant, apoptosis, detoxification, and heat shock mechanism. However, cumin essential oil increased the dose-dependently positive effect on certain genes in tissues of the heat-stressed broilers and downregulated (except for Bcl-2) these genes.

Effects of Different Eimeria Inoculation Doses on Growth Performance, Daily Feed Intake, Gut Health, Gut Microbiota, Foot Pad Dermatitis, and Eimeria Gene Expression in Broilers Raised in Floor Pens for 35 Days

The study was conducted to investigate the effects of different Eimeria inoculation doses on the growth performance, gut ecosystem, and body composition of broilers in floor pens for 35 days. A total of 750 15-day-old broilers were allocated to five experimental groups with six replicate pens. The five experimental groups included unchallenged control (CON); Eimeria dose 1 (ED1): E. acervulina: 31,250/E. maxima: 6250/E. tenella: 6250; Eimeria dose 2 (ED2): E. acervulina: 62,500/E. maxima: 12,500/E. tenella: 12,500; Eimeria dose 3 (ED3): E. acervulina: 125,000/E. maxima: 25,000/E. tenella: 25,000; and Eimeria dose 4 (ED4): E. acervulina: 250,000/E. maxima: 50,000/E. tenella: 50,000. On D 21, BW were linearly reduced by increased Eimeria inoculation doses (p < 0.01). On D 35, the Eimeria challenge groups had significantly lower BW compared to the CON group. Increased Eimeria inoculation doses linearly decreased crude fat (CF) (p < 0.01) on D 21. Increased Eimeria inoculation doses tended to increase the relative abundance of the phylum Proteobacteria (p = 0.098) on D 21. On D 35, lean:fat was linearly reduced by increased Eimeria inoculation doses (p < 0.05). Eimeria infection negatively influenced growth performance and gut health in broilers in the acute phase, and the negative effects were prolonged to D 35 in floor pen conditions.

(-)-Epigallocatechin-3-Gallate Attenuates the Adverse Reactions Triggered by Selenium Nanoparticles without Compromising Their Suppressing Effect on Peritoneal Carcinomatosis in Mice Bearing Hepatocarcinoma 22 Cells

Increasing evidence shows that selenium and polyphenols are two types of the most reported compounds in tumor chemoprevention due to their remarkable antitumor activity and high safety profile. The cross-talk between polyphenols and selenium is a hot research topic, and the combination of polyphenols and selenium is a valuable strategy for fighting cancer. The current work investigated the combination anti-peritoneal carcinomatosis (PC) effect of selenium nanoparticles (SeNPs) and green tea (Camellia sinensis) polyphenol (-)-epigallocatechin-3-gallate (EGCG) in mice bearing murine hepatocarcinoma 22 (H22) cells. Results showed that SeNPs alone significantly inhibited cancer cell proliferation and extended the survival time of mice bearing H22 cells. Still, the potential therapeutic efficacy is accompanied by an approximately eighty percent diarrhea rate. When EGCG was combined with SeNPs, EGCG did not affect the tumor proliferation inhibition effect but eliminated diarrhea triggered by SeNPs. In addition, both the intracellular selectively accumulated EGCG without killing effect on cancer cells and the enhanced antioxidant enzyme levels in ascites after EGCG was delivered alone by intraperitoneal injection indicated that H22 cells were insensitive to EGCG. Moreover, EGCG could prevent SeNP-caused systemic oxidative damage by enhancing serum superoxide dismutase, glutathione, and glutathione peroxidase levels in healthy mice. Overall, we found that H22 cells are insensitive to EGCG, but combining EGCG with SeNPs could protect against SeNP-triggered diarrhea without compromising the suppressing efficacy of SeNPs on PC in mice bearing H22 cells and attenuate SeNP-caused systemic toxicity in healthy mice. These results suggest that EGCG could be employed as a promising candidate for preventing the adverse reactions of chemotherapy including chemotherapy-induced diarrhea and systemic toxicity in cancer individuals.

Gut Microbiota, Intestinal Morphometric Characteristics, and Gene Expression in Relation to the Growth Performance of Chickens

this study aimed to investigate the growth mechanism in a local breed of chickens by comparing the highest weight (HW) and the lowest weight in their microbiota, histological characteristics, and gene expression. Golden Montazah chickens, an Egyptian breed, were reared until they were 49 days old. All of the birds were fed ad libitum by a starter diet from day 1 until day 21, followed by a grower diet from day 21 to the end of the study. At 49 days old, the forty-eight birds with the heaviest body weight (HW) and the lightest body weight (LW) were chosen. Blood biochemical and histological morphometric parameters, electron microscopy, and intestinal nutrient transporter gene expression were studied in the sampled jejunum. The microbial composition and functions of the content and mucosa in HW and LW chickens were studied using 16S rRNA gene sequencing. The histological morphometric parameters were all more significantly (p < 0.05) increased in the HW chickens than in the LW chickens. Total protein, albumin, and triglycerides in serum were significantly higher (p < 0.05) in the HW chickens than in the LW chickens. The microbiome profile in the gut showed that Microbacterium and Sphingomonas were positively correlated with the body weights. In the local breed, there were significant differences in the intestinal microstructure which could enhance the growth mechanism and body weight. Our findings showed that some microbial components were significantly associated with body weight and their interactions with the host could be inferred to explain why these interactions might alter the host’s metabolic responses. Further investigation into combining bioinformatics with lab experiments in chickens will help us to understand how gut bacteria can change the host’s metabolism by special metabolic features in the gastrointestinal system.

Adverse effects of heat stress during summer on broiler chickens production and antioxidant mitigating effects

Broiler chicken meat is a good source of protein consumed universally, and is one of the most commonly farmed species in world. In addition to providing food, poultry non-edible byproducts also have value. A major advantage of broiler chicken production is their short production cycle, which results in a greater rate of production in comparison to other species. However, as with any production system, there are constraints in broiler production with one of the most pressing being energy requirements to keep the birds warm as chicks and cool later in the growth cycle, as a result of the cost needing mechanical heating and cooling. While this is feasible in more advanced economies, this is not readily affordable in developing economies. As a result, farmers rely on natural ventilation to cool the rearing houses, which generally becoming excessively warm with the resultant heat stress on the birds. Since little can be done without resorting to mechanical ventilation and cooling, exploring the use of other means to reduce heat stress is needed. For this review, we cover the various factors that induce heat stress, the physiological and behavioral responses of broiler chickens to heat stress. We also look at mitigating the adverse effect of heat stress through the use of antioxidants which possess either an anti-stress and/or antioxidant effects.

Epigallocatechin-3-gallate ameliorates liver injury secondary to Pseudomonas aeruginosa pneumonia

Pseudomonas aeruginosa is a dangerous pathogen causing nosocomial pneumonia. P. aeruginosa infection-induced liver damage is another fatal threat, and antibiotic treatment is not effective in relieving P. aeruginosa virulence-triggered damage. We here evaluated the protective effect of epigallocatechin gallate (EGCG), a substance that inhibits virulence of P. aeruginosa through quorum quenching, on liver damage secondary to P. aeruginosa infection. Mice were pretreated with EGCG (20, 40, and 80 mg/kg) for 3 days, and then infected with P. aeruginosa through intratracheal instillation to model acute pneumonia. The mice were sacrificed after 24 h of infection, and samples were harvested for subsequent analysis. EGCG significantly decreased the serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Histopathological changes of liver were significantly ameliorated by EGCG. It also significantly reduced oxidative stress that induced liver damage in P. aeruginosa infection, which relied not on the activation of the Nrf2-HO-1 pathway but on the upregulation of the activity of antioxidative enzymes. Then, the inflammatory response in the liver was tested. EGCG inhibited the release of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) by blocking the inflammation regulating signaling of the TLR4-myD88-NF-κB pathway. EGCG upregulated the activation of nuclear receptors to stronger the liver protective activity against P. aeruginosa infection. Conclusively, EGCG exhibited a significant hepatoprotective effective against P. aeruginosa infection.

Effects of Dietary L-Theanine on Growth Performance, Antioxidation, Meat Quality, and Intestinal Microflora in White Feather Broilers With Acute Oxidative Stress

In order to reduce the negative effects caused by oxidative stress on broilers, it is particularly important to find ways to alleviate oxidative stress. As a natural plant extract, L-theanine has a variety of biological effects, such as improving antioxidant capacity, promoting growth, and enhancing immunity and antitumor. This trial evaluated the effects of dietary supplementation of L-theanine on growth performance, antioxidation, meat quality, and intestinal microflora in 817 White Feather Broilers. A total of 108 21-day-old 817 broilers with similar body weight (BW) were randomly divided into three groups with six replicates per group and six chickens within each replicate. The three groups were corn-soybean-based diet (NC group); basal diet plus drinking water with 30 mg hydrocortisone/kg (PC group); and basal diet supplemented with 400 mg L-theanine/kg plus drinking water with 30 mg hydrocortisone/kg (LT group). Compared with the NC group, from 21 to 24 days of age, the PC and LT groups had decreased BW, average daily gain (ADG), and average daily feed intake (ADFI), and increased feed to gain ratio (F/G; p < 0.05). At 24 days of age, the LT group had improved superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in serum as compared to the NC group (p < 0.05). The LT group broilers also had significantly higher concentrations of malondialdehyde (MDA) in serum and liver (p < 0.05). On the 42nd days, the PC group had lower PH_45min (p < 0.05) than the NC and LT groups and higher cooking loss and shear force (p < 0.05). Moreover, the villi height of the PC group was significantly lower in jejunum than the NC group (p < 0.05). The LT group had a higher ZO-1 content in duodenum than the NC and PC groups (p < 0.05). The activity of GSH-Px in the liver of the LT group was increased than in the PC group (p < 0.05). The relative abundance of Firmicutes in the LT group was significantly higher than in the NC and PC groups (p < 0.05). These results suggested that the effects of acute oxidative stress on growth performance and meat quality of broilers are continuous, and dietary supplementation of L-theanine could improve the growth performance and meat quality, enhance the intestinal mucosal barrier and antioxidant capacity, and improve the composition of the intestinal flora of broilers caused by acute oxidative stress.

Effect of probiotic supplementation on the expression of tight junction proteins, innate immunity-associated genes, and microbiota composition of broilers subjected to cyclic heat stress

This study investigated the effects of probiotic on intestinal innate immunity-associated gene expression and cecal microbiota in heat-stressed broilers. A total of 180 21-day-old male broilers were randomly assigned to three treatment groups with four replicates per group. The thermoneutral group (TN) (23 ± 1°C) received a basal diet, and another two heat-stressed groups (28-35-28°C for 12 h daily) were fed the basal diet (HS) or the basal diet supplemented with probiotic at a dose of 1.5 × 10⁸  CFU/kg (HS_Pro) for 21 consecutive days. Compared with the TN group, the abundance of beneficial bacteria was decreased (p < 0.05) in the caecum of heat-stressed broilers. Heat stress downregulated (p < 0.05) the expression of Toll-like receptor (TLR)2 and upregulated (p < 0.05) the expressions of TLR5, TLR15, avian β-defensin (AvBD)4, AvBD8, and AvBD14 in the ileum as compared with the TN group. Dietary supplementation of probiotic upregulated (p < 0.05) the occludin expression in the ileum, improved the microbiota balance in the caecum, and decreased (p < 0.05) the gene expressions of TLR5 and TLR15 in the ileum of heat-stressed broilers. Collectively, dietary probiotic supplementation could promote intestinal barrier function via improving gut microbiota community and regulating innate immunity-associated gene expressions in heat-stressed broilers.

Functional roles of taurine, L-theanine, L-citrulline, and betaine during heat stress in poultry

Heat stress (HS) is an important environmental stress factor affecting poultry production on a global scale. With the rise in ambient temperature and increasing effects of global warming, it becomes pertinent to understand the effects of HS on poultry production and the strategies that can be adopted to mitigate its detrimental impacts on the performance, health, welfare, immunity, and survival of birds. Amino acids (AAs) have been increasingly adopted as nutritional modifiers in animals to ameliorate the adverse effects of HS. They are essential for protein synthesis, growth, maintenance, reproduction, immunity, stress response, and whole-body homeostasis. However, HS tends to adversely affect the availability, transport, absorption, and utilization of these AAs. Studies have investigated the provision of these AAs to poultry during HS conditions, and variable findings have been reported. Taurine, L-theanine, and L-citrulline are non-essential amino acids that are increasingly gaining attention as nutritional supplements in HS animals. Similarly, betaine is an amino acid derivative that possesses favorable biological properties which contributes to its role as a functional additive during HS. Of particular note, taurine is negligible in plants, while betaine, L-theanine, and L-citrulline can be found in selected plants. These nutrients are barely found in feed ingredients, but their supply has been shown to elicit important physiological roles including anti-stress effects, anti-oxidative, anti-inflammatory, gut promoting, and immunomodulatory functions. The present review provides information on the use of these nutritionally and physiologically beneficial nutrients as functional additives to poultry diets during HS conditions. Presently, although several studies have reported on the positive effects of these additives in human and murine studies, however, there is limited information regarding their utilization during heat stress in poultry nutrition. Therefore, this review aims to expound on the functional properties of these nutrients, their potentials for HS alleviation, and to stimulate further researches on their biological roles in poultry nutrition.

Effects of Dietary Supplementation with Epigallocatechin Gallate on Meat Quality and Muscle Antioxidant Capacity of Broilers Subjected to Acute Heat Stress

Simple Summary

Broilers are readily affected by acute heat stress (AHS), and the development of intensive and high-density management and the occurrence of high temperatures during the summer exacerbate this problem. AHS has undesirable effects on animal immunity, meat quality, antioxidant capacity, and welfare of broilers, which can be alleviated by nutrition regulation. Epigallocatechin gallate (EGCG) has been found to reduce the damage of AHS on growth performance, antioxidant capacity, and the expression of nuclear factor erythroid 2-related 2 (Nrf2) in liver and jejunum. However, there are few reports on the effect and mechanism of action of EGCG on meat quality and antioxidant function in broilers under AHS. We demonstrated that EGCG protects against AHS-impaired meat quality by improving muscle antioxidant capacity, which seems to be associated with the activation of the Nrf2 signaling pathway. Moreover, these findings suggested that EGCG could be an effective additive to improve meat quality and muscle redox balance by regulating the Nrf2 signaling pathway.

Abstract

This study evaluated epigallocatechin gallate’s (EGCG’s, 400 mg/kg) effect on meat quality and muscle antioxidant status of broilers under acute heat stress (AHS). A total of 144 21-day-old male Huainan partridge chickens were randomly allocated to the EGCG-free group (12 replicates) and the EGCG group (6 replicates). On day 94, the EGCG-free group was divided into the control group (CON) and the AHS group, and then AHS group and EGCG group (identified as AHS + EGCG group) were treated with AHS (33 ± 1 °C for 12 h). AHS increased (p < 0.05) L*_24h, drip loss, muscle lactic acid, malondialdehyde (MDA) contents, and kelch-like ECH-associated protein 1 (Keap1) mRNA level, and decreased (p < 0.05) eviscerated percentage, pH_24h, a*, muscle total superoxide dismutase (T-SOD) activity, the ratio of T-SOD/MDA and glutathione peroxidase /MDA, glycogen content, and nuclear factor erythroid 2-related 2 (Nrf2), catalase (CAT), NAD(P)H/quinone dehydrogenase 1 (NQO1) mRNA levels. The AHS + EGCG group exhibited lower (p < 0.05) L*_24h, drip loss, muscle lactic acid, MDA contents and Keap1 mRNA level, and greater (p < 0.05) eviscerated percentage, pH_24h, a*, muscle T-SOD activity, the ratio of T-SOD/MDA, Nrf2, and NQO1 mRNA levels compared with the AHS group. In conclusion, EGCG protects against AHS-impaired meat quality by improving muscle antioxidant capacity, which seems to be associated with the activation of the Nrf2 signaling pathway.

(-)-Epigallocatechin-3-gallate mitigates cyclophosphamide-induced intestinal injury by modulating the tight junctions, inflammation and dysbiosis in mice

Cyclophosphamide (CTX) is an antitumor drug commonly used to treat various cancer types. Unfortunately, its toxic side effects, including gastrointestinal (GI) toxicity, affect treatment compliance and patients' prognosis. Thus, there is a critical need of evaluating strategies that may improve the associated GI toxicity induced by CTX. In this work, we evaluated the capacity of epigallocatechin-3-gallate (EGCG), a major constituent of green tea, to improve the recovery of gut injury induced by CTX in mice. Treatment with CTX for 5 days severely damaged the intestinal structure, increased immune-related cytokines (TNFα, IL-10 and IL-21), reduced the expression levels of tight junction proteins (ZO-1, occludin, claudin-1), induced reactive oxygen species, altered the composition of gut microbiota, and reduced short chain fatty acid levels. EGCG treatment, starting one day after the last CTX dose, significantly improved the intestinal structure, ameliorated gut permeability, and restored ZO-1, occludin and claudin-1 levels. Moreover, EGCG reduced TNFα, IL-10 and IL-21 levels and decreased oxidative stress by regulating the activities of the antioxidant enzymes catalase, superoxide dismutase and glutathione peroxidase. Finally, EGCG treatment restored the composition of gut microbiota and the levels of the short chain fatty acids. In conclusion, these findings indicate that EGCG may function as an effective bioactive compound to minimize CTX-induced GI tract toxicity.

Growth performance, intestinal histomorphology, gut microflora and ghrelin gene expression analysis of broiler by supplementing natural growth promoters: A nutrigenomics approach

In an epoch of escalating number of antibiotic-resistance bacteria, there is a dire need to develop efficient and novel feeding strategies for animal nutrition as alternatives to antibiotics. Here, implicating nutrigenomic approach, phytobiotics and organic acids were used to evaluate ghrelin gene expression levels, gut microflora composition, performance parameters and intestinal histomorphological changes in broiler chickens. One-day-old chicks (n = 315) were reared for 42 days and distributed randomly into five experimental groups; each with three replicates (21 birds per replicate). Experimental groups were control: basal diet only, antimicrobial growth promoter: 40 g/metric ton of basal diet (virginiamycin), organic acids: 4 kg/metric ton of basal diet, phytobiotics: 3 kg/metric ton of basal diet, combination: 7 kg/metric ton of basal diet (organic acids 4 kg and phytobiotics 3 kg metric ton of feed). Growth performance, histological and ghrelin gene expression analysis were executed on 21 and 42 days while, quantitative bacterial analysis of cecum and ileum was performed on day 42. Increased feed intake and body weight (p < 0.05) were noticed in phytobiotics group. Addition of phytobiotics significantly improved (p < 0.05) villus height and ratio of villus height/crypt depth in ileum, jejunum, and duodenum and down-regulated ghrelin gene expression levels. Total coliform and Escherichia coli in cecal and ileal digesta were decreased significantly (p < 0.05) in organic acids group. Correlation analysis revealed Lactobacillus spp. were positively correlated to villus height/crypt depth ration in duodenum. The findings indicated the importance of gene-nutrient-microbiota interactions based on nutrigenomics approach. Hence, phytobiotics and organic acids might be suitable alternatives to antibiotics for improved performance and immunity, along with healthier meat production in poultry.

New insights into the role of the Nrf2 signaling pathway in green tea catechin applications

Nuclear factor-erythroid 2-related factor 2 (Nrf2) is a transcriptional signaling pathway that plays a crucial role in numerous clinical complications. Pivotal roles of Nrf2 have been proved in cancer, autoimmune diseases, neurodegeneration, cardiovascular diseases, diabetes mellitus, renal injuries, respiratory conditions, gastrointestinal disturbances, and general disorders related to oxidative stress, inflammation, apoptosis, gelatinolysis, autophagy, and fibrogenesis processes. Green tea catechins as a rich source of phenolic compounds can deal with various clinical problems and manifestations. In this review, we attempted to focus on intervention between green tea catechins and Nrf2. Green tea catechins especially epigallocatechin gallate (EGCG) elucidated the protective role of Nrf2 and its downstream molecules in various disorders through Keap-1, HO-1, NQO-1, GPx, GCLc, GCLm, NF-kB cross-link, kinases, and apoptotic proteins. Subsequently, we compiled an updated expansions of the Nrf2 role as a gate to manage and protect different disorders and feasible indications of green tea catechins through this signaling pathway. The present review highlighted recent evidence-based data in silico, in vitro, and in vivo studies on an outline for future clinical trials.

Effect of probiotic supplementation on growth performance, intestinal morphology, barrier integrity, and inflammatory response in broilers subjected to cyclic heat stress

This study investigated the protective effects of probiotic on heat stress-induced intestinal injury and inflammatory response in broilers. A total of 180 male broilers were randomly allocated to three treatments with four replicates each from 22 to 42 days of age. The broilers were either raised under thermoneutral (TN) conditions (23 ± 1°C) or subjected to cyclic heat stress (28-35-28°C for 12 hr daily). The broilers kept at TN conditions were fed a basal diet, and those exposed to heat stress were fed basal diets supplemented with or without probiotic at a dose of 1.5 × 10⁸  cfu/kg. Compared with the TN group, heat stress decreased (p < .05) the growth performance, reduced (p < .05) villus height and villus height: crypt depth ratio in intestinal mucosa, increased (p < .05) serum levels of D-lactic acid on day 28 and endotoxin, TNF-α and IL-6 on day 42, and decreased (p < .05) serum IL-10 content on day 42. Dietary supplementation of probiotic reversed (p < .05) all these changes except for the growth performance in heat-stressed broilers. In conclusion, dietary inclusion of probiotic could improve intestinal morphology and barrier function, alleviate inflammatory response, but exert no ameliorative effect on growth performance of broilers under cyclic heat stress.

Evaluation of the Relationship between Adipose Metabolism Patterns and Secretion of Appetite-Related Endocrines on Chicken

Simple Summary

The weight of an animal conforms to a certain growth pattern. Among others, feed, environment, and body composition, in addition to genetics, affect the animal’s feed consumption and body weight. Under normal circumstances, the body weight of an animal is mainly affected by feed intake, and body composition may significantly influence feed intake. Therefore, this report sets out the effects of fat accumulation on lipid metabolism and appetite, and finally introduces the effects of feeding patterns on animal feed intake.

Abstract

In addition to the influence of genes, the quality of poultry products is mainly controlled by the rearing environment or feed composition during rearing, and has to meet human use and economical needs. As the only source of energy for poultry, feed considerably affects the metabolic pattern of poultry and further affects the regulation of appetite-related endocrine secretion in poultry. Under normal circumstances, the accumulation of lipid in adipose reduces feed intake in poultry and increases the rate of adipose metabolism. When the adipose content in cells decreases, endocrines that promote food intake are secreted and increase nutrient concentrations in serum and cells. By regulating the balance between appetite and adipose metabolism, the poultry’s growth and posture can maintain a balanced state. In addition, increasing fiber composition in feed can effectively increase poultry welfare, body weight, lean composition and antioxidant levels in poultry. According to this, the concept that proper fiber content should be added to feed should be considered for better economic benefits, poultry welfare and meat productivity.

In vitro and in vivo antioxidant activity of eucalyptus leaf polyphenols extract and its effect on chicken meat quality and cecum microbiota

While eucalyptus leaf polyphenols extract (EPE) has been evaluated for its various bioactivities, few studies thus far have focused on its systemic antioxidant activity or its effects in chickens in relation to meat quality or the intestinal microbiome. Therefore, the goal of this study was to investigate the antioxidant activity of EPE in vitro and in vivo, and to evaluate its effect on chicken meat quality and cecum microbiota. In this study, EPE scavenged DPPH free radical, ABTS free radical, and superoxide radical, and showed strong reducing power in chemical-based assay. EPE protected RAW264.7 cells from H₂O₂-induced oxidative damage by improving total superoxide dismutase (T-SOD) activity, catalase (CAT) activity and glutathione (GSH) content, decreasing malondialdehyde (MDA) content. Additionally, EPE dietary supplementation was found to increase chicken meat antioxidant levels and quality. Furthermore, chickens fed a diet supplemented with EPE had differentially changed cecal microbial compositions when compared to controls. EPE supplementation notably improved the α-diversity of the cecum. The Firmicutes/Bacteroidetes ratio and the relative abundance of Verrucomicrobia at the phylum level were clearly enhanced in the cecum with EPE supplementation (p < 0.05), with the relative abundance of Subdivision 5 genera incertae sedis and Aminivibrio enriched at genus level (p < 0.05). Therefore, these findings indicate that EPE is a good source of natural antioxidants and could be used as antioxidant supplements in animal feed and other foods, contributing to gut health improvement.

Effect of chronic cyclic heat stress on the intestinal morphology, oxidative status and cecal bacterial communities in broilers

The objective of this study was to examine the effects of chronic cyclic heat stress (HS) on the intestinal morphology, oxidative stress and cecal bacterial communities of broilers. One-day-old Arbor Acres (AA) male broilers (n = 100) were acclimated for 3 weeks and then randomly allocated into two groups, normal control (NC) group (22 ± 1 °C, 24 h/day) and HS group (32 ± 1 °C, 10 h/day lasted for 2 weeks). At 35 d of age, intestinal segments (duodenum, jejunum and ileum) and cecal digesta were collected for detection. HS affected intestinal morphology, inducing epithelial cell abscission, inflammatory cell infiltration, and lamina propria edema. Compared with the NC group, HS significantly decreased (P < 0.01) villus height (VH) and the VH-to-crypt depth (CD) ratio (VCR), increased (P < 0.05) CD in the duodenum and ileum, but had no effect on the VH in the jejunum. Moreover, HS induced oxidative stress with antioxidant enzymes activity decreasing (P < 0.05) while malondialdehyde (MDA) content increasing (P < 0.05) in small intestine. Pearson's correlation analysis indicated that MDA content was negatively correlated with VH (P < 0.05). The result of 16S rRNA sequencing showed that HS exposure impacted cecal microbiota alpha diversity (phylogenetic diversity whole-tree index) and beta diversity. Based on principal coordinate analysis (PCoA) plots for weighted UniFrac metrics and unweighted pair group method with arithmetic mean (UPGMA), there were 8 discriminative features at the genus level (linear discriminant analysis score > 2). Parabacteroides, Saccharimonas, Romboutsia and Weissella were reduced, while Anaerofustis, Pseudonocardia, Rikenella and Tyzzerella were enriched in heat-stressed broilers. Collectively, these results indicated that chronic cyclic HS induced oxidative stress that caused damage to intestinal villus-crypt structures, and then altered the cecal microflora profile.