Effects of gingerols-rich extract of ginger on growth performance, serum metabolites, meat quality and antioxidant activity of heat-stressed broilers

Bioresponsive gingerol-loaded alginate-coated niosomal nanoparticles for targeting intracellular bacteria and cancer cells

Targeting and treating intracellular pathogen infections has been long-standing challenge, particularly in light of the escalating prevalence of antimicrobial resistance. Herein, an optimum formulation of alginate (AL)-coated niosome-based carriers for delivery of herbal extract Gingerol (Gin) was developed to treat intracellular pathogen infections and cancer cells. We used Gin-Nio@AL as a model drug to assess its efficacy against Gram-negative/positive bacteria and breast cancer cell lines. Our investigation affirmed its heightened antibacterial and anticancer properties. The antibacterial activity of Gin-Nio@AL against intracellular Staphylococcus aureus (S. aureus) and pseudomonas aeruginosa (P. aeruginosa) was also tested. In the current study, the niosome nanoparticles containing herbal extract Gingerol were optimized regarding lipid content and Surfactant per Cholesterol molar ratio. The developed formulation provided potential advantages, such as smooth globular surface morphology, small diameter (240.68 nm), pH-sensitive sustained release, and high entrapment efficiency (94.85 %). The release rate of Gin from AL-coated niosomes (Gin-Nio@AL) in physiological and acidic pH is lower than uncoated nanoparticles (Gin-Nio). Besides, the release rate of Gin from niosomal formulations increased in acidic pH. The Gin-Nio@AL demonstrated good antimicrobial activity against S. aureus and P. aeruginosa, and compared to Gin-Nio, the MIC values decreased to 7.82 ± 0.00 and 1.95 ± 0.00 μg/mL, respectively. In addition, the time-kill assay results showed that the developed formulation significantly reduced the number of bacteria in both strains compared to other tested groups. The microtiter data and scanning electron microscope micrography showed that Gin-Nio@AL has a more significant inhibitory effect on biofilm formation than Gin-Nio and Gin. The cell cytotoxicity evaluation showed that Gin-Nio@AL reduced the survival rate of MDA-MB-231 cancer cells to 52.4 % and 45.2 % after 48 h and 72 h, respectively. The elimination of intracellular pathogens was investigated through a breast cancer cell infection in an in vitro model. Gin-Nio@AL exhibited an enhanced and sustained intracellular antibacterial activity against pathogens-infected breast cancer cells compared to other tested formulations. Overall, Gin-Nio@AL enables the triggered release and targeting of intra-extra cellular bacteria and cancer cells and provides a novel and promising candidate for treating intracellular pathogen infections and cancer cells.

Biogenic Selenium Nanoparticles Synthesized Using Alginate Oligosaccharides Attenuate Heat Stress-Induced Impairment of Breast Meat Quality via Regulating Oxidative Stress, Metabolome and Ferroptosis in Broilers

Selenium (Se) is an indispensable trace element with versatile functions in antioxidant defense in poultry. In our previous study, we synthesized a novel type of biogenic selenium nanoparticle based on alginate oligosaccharides (SeNPs-AOS), and found that the particles are sized around 80 nm with an 8% Se content, and the dietary addition of 5 mg/kg of SeNPs-AOS could effectively alleviate the deleterious effects of heat stress (HS) in broilers, but it is still unclear whether SeNPs-AOS can improve the meat quality. Therefore, the aim of this study was to evaluate the protective effects of SeNPs-AOS on breast meat quality in heat-stressed broilers, and explore the relevant mechanisms. Birds at the age of 21 days were randomly divided into four groups with six replicates per group (eight broilers per replicate) according to a 2 × 2 experimental design, using HS (33 ± 2 °C, 10 h/day vs. thermoneutral, TN, under 23 ± 1.5 °C) and SeNPs-AOS (5 mg/kg feed vs. no inclusion) as variables. The results showed that dietary SeNPs-AOS decreased the cooking loss (p < 0.05), freezing loss (p < 0.001), and shear force (p < 0.01) of breast muscle in heat-stressed broilers. The non-targeted metabolomics analysis of the breast muscle identified 78 differential metabolites between the HS and HS + SeNPs-AOS groups, mainly enriched in the arginine and proline metabolism, β-alanine metabolism, D-arginine and D-ornithine metabolism, pantothenate, and CoA biosynthesis pathways (p < 0.05). Meanwhile, supplementation with SeNPs-AOS increased the levels of the total antioxidant capacity (T-AOC), the activities of catalase (CAT) and glutathione peroxidase (GSH-Px), and decreased the content of malondialdehyde (MDA) in the breast muscle (p < 0.05) in broilers under HS exposure. Additionally, SeNPs-AOS upregulated the mRNA expression of CAT, GPX1, GPX3, heme oxygenase-1 (HO-1), masculoaponeurotic fibrosarcoma G (MafG), MafK, selenoprotein W (SELENOW), SELENOK, ferritin heavy polypeptide-1 (FTH1), Ferroportin 1 (Fpn1), and nuclear factor erythroid 2-related factor 2 (Nrf2) (p < 0.05), while it downregulated Kelch-like ECH-associated pro-36 tein 1 (Keap1) and prostaglandin-endoperoxide Synthase 2 (PTGS2) expression (p < 0.05) in broilers under HS. These findings demonstrated that the dietary addition of SeNPs-AOS mitigated HS-induced oxidative damage and metabolite changes in the breast muscle of broilers, which may be related to the regulation of the Nrf2 signaling pathway and selenoprotein synthesis. In addition, SeNPs-AOS upregulated the breast muscle gene expression of anti-ferroptosis-related molecules in broilers under HS, suggesting that SeNPs-AOS can be used as novel Se supplements against HS in broilers.

Ginger Bioactives: A Comprehensive Review of Health Benefits and Potential Food Applications

Ginger is an herbaceous and flowering plant renowned for its rhizome, which is widely employed as both a spice and an herb. Since ancient times, ginger has been consumed in folk medicine and traditional cuisines for its favorable health effects. Different in vitro and in vivo studies have disclosed the advantageous physiological aspects of ginger, primarily due to its antioxidant, anti-inflammatory, antimicrobial, and anti-carcinogenic properties. These health-promoting features are linked to the variety of bioactive compounds that are present in ginger. Following the advancement in consumer awareness and the industrial demand for organic antioxidants and functional ingredients, the application of ginger and its derivatives has been broadly investigated in a wide range of food products. The prominent features transmitted by ginger into different food areas are antioxidant and nutraceutical values (bakery); flavor, acceptability, and techno-functional characteristics (dairy); hedonic and antimicrobial properties (beverages); oxidative stability, tenderization, and sensorial attributes (meat); and shelf life and sensorial properties (film, coating, and packaging). This review is focused on providing a comprehensive overview of the tendencies in the application of ginger and its derivatives in the food industry and concurrently briefly discusses the beneficial aspects and processing of ginger.

Potential effects of gingerol topical application on components of the innate immunity in lactating goat mammary glands

In the mammary glands, production of antimicrobial components and formation of less-permeable tight junctions (TJs) are important for safe milk production. Previously, we reported that local heat treatment of udders using disposable heating pad enhances the components of innate immunity in lactating goat mammary glands. Gingerol is a polyphenol present in ginger that can induce heat-like effects. However, oral administration of polyphenols causes a decrease in biological activity through conjugation and metabolic conversion. Here, we investigated the effects of gingerol on antimicrobial components and TJs by topically applying it to lactating goat udders. Gingerol application increased the somatic cell count, cathelicidin-2 concentration, and proportion of polymorphonuclear cells in the milk and interleukin-8 production. Moreover, gingerol treatment enhanced β-defensin-1 production in milk, cultured mammary epithelial cells, and cultured somatic cells. Contrastingly, gingerol treatment did not affect the concentrations of blood-derived components (Na+, albumin, and IgG) in the milk or the TJ barrier function of cultured mammary epithelial cells. These findings suggest that the topical application of gingerol, similar to local heat treatment, to udders enhances the components of innate immunity in mammary glands. These findings may be useful for the prevention of mastitis in milk-producing animals and, hence, safe and stable dairy production.

Role of oral phytogenic supplementation to protect cardiac, hepatic, nephrotic, and splenic oxidative stress in broiler chickens

This study investigated the effects of adding essential oils of garlic, ginger, turmeric, and cinnamon to drinking water on cardiac, hepatic, nephrotic, and splenic oxidative status of broiler chickens. A batch of 200 1-d old Arbo acre broiler chicks was administered with Control (Water: no additive), 30 ml/L of cinnamon, ginger, turmeric, or garlic essential oils in drinking water for 42 d. On day 43, three broiler chickens/replicates were sampled randomly, sacrificed, and eviscerated. The hearts, spleens, kidneys, and livers were excised and assayed for glutathione peroxidase, total antioxidant activity, catalase, superoxide dismutase, and lipid peroxidation using standard protocols. In spleen broiler chickens, all additive essential oils increased (P < 0.05) total antioxidant activity. Catalase, superoxide dismutase, and glutathione peroxidase significantly increased (P < 0.05) in garlic, ginger, and turmeric essential oils except cinnamon. In kidney broiler chickens, lipid peroxidation was significantly reduced (P < 0.05) in all the additive essential oils. Garlic, cinnamon, and ginger essential oils increased (P < 0.05) catalase, superoxide dismutase, and glutathione peroxidase in kidney broiler chickens. In liver broiler chickens, lipid peroxidation, and glutathione peroxidase were higher (P < 0.05) in cinnamon essential oil than other additive essential oils. Superoxide dismutase and catalase were higher (P < 0.05) in turmeric essential oils. In heart broiler chickens, all the additive essential oils significantly decreased (P < 0.05) lipid peroxidation and increased (P < 0.05) total antioxidant activity. In conclusion, oral garlic, turmeric, and ginger essential oils supplementation did not reduce lipid peroxidation in spleen, whereas cinnamon essential oil caused lipid peroxidation in liver of broiler chickens.

Impact of Dietary Supplementation of Spice Extracts on Growth Performance, Nutrient Digestibility and Antioxidant Response in Broiler Chickens

This study aimed to investigate the effects of supplementing broiler chicken diets with an encapsulated product based on capsicum and other spice (black pepper and ginger) extracts on growth performance, nutrient digestibility, digestive enzyme activity and antioxidant response. To this end, 480 1-day-old male chicks were randomly assigned to two experimental treatments (12 pens/treatment; 20 birds/pen). Dietary treatments included a basal diet with no additives (CONTROL) and a basal diet supplemented with 250 ppm of the spice additive (SPICY; Lucta S.A., Spain). Supplementation of SPICY increased body weight (p < 0.05) compared with CONTROL at 7 d of age and improved (p < 0.01) ADG from 0 to 7 d of age. The apparent ileal digestibility of dry matter, gross energy and crude protein was higher (p < 0.05) in birds fed the SPICY diet compared with the CONTROL diet. Birds fed SPICY showed lower (p < 0.05) plasma catalase (CAT) activity, and the hepatic gene expression of CAT and Nrf2 was down-regulated (p < 0.05) compared with the CONTROL. In conclusion, the inclusion of 250 ppm of SPICY in broiler diets improved growth performance at 7 d of age and positively affected nutrient digestibility and antioxidant response.

The anti-oxidative potential of ginger extract and its constituent on meat protein isolate under induced Fenton oxidation

Ginger extract has been reported to possess antioxidant properties. However, components isolated from ginger have been rarely reported to inhibit oxidation. Herein, the antioxidant properties of ginger and purified components derived from it (6-gingerol, zingerone, rutin, quercetin, and kaempferol) were confirmed by using HPLC and were further used to investigate its effect on lamb meat. Myofibrillar proteins isolated (MPI) from lamb meat were incubated with ginger and its constituents under induced Fenton oxidation (1.0 mmol/L FeCl3, 0.1 mmol/L Asc, and 20 mmol/L H2O2) for 1, 3,5, and 7 h. Incubating meat protein isolate in the absence of ginger extract or its components resulted in a substantial drop in sulfhydryl groups, an increase in protein carbonyl content, and a corresponding increase in TBARS content. However, ginger extract and its constituents demonstrated antioxidant properties, which might be attributed to their hydroxyl groups and suitable solubilizing side chains. Overall, ginger extract exhibited the highest antioxidant capabilities of all treated samples, suggesting that ginger extracts may be used as a natural antioxidant in meat and lipid/protein-containing processed products. SIGNIFICANCE OF THE STUDY: Ginger extract is also frequently used as a herbal medicine due to its anti-inflammatory, anti-cancer, and antibacterial qualities. Nonvolatile pungent chemicals found in ginger, such as gingerol, shogaols, paradols, and zingerone, as well as kaempferol, rutin, and other phenolic compounds, have been confirmed in ginger extract and have been shown to have antioxidant action driven by free radical elimination. Despite these findings, ginger extract and its pure constituent components have seldom been shown to have the ability to slow protein and lipid oxidation in meat and meat-related products. The effect of ginger extracts on the oxidative stability of myofibriller protein isolate has never been investigated. Exploiting the phenolic content of ginger extract may result in a discovery that would have a huge influence on both the ginger and meat industries as well as other food processing sectors. The first aim of our study was to confirm the presence of six selected phenolic compounds (rutin, kaempferol, 6-gingerol, zingerone, naringenin, and quercetin) in ginger as reported by literature, and the second objective was to determine the efficacy of ginger extracts and its purified constituents on myofibrillar protein isolate treated under induced Fenton oxidation.

Microencapsulated basil oil (Ocimum basilicum Linn.) enhances growth performance, intestinal morphology, and antioxidant capacity of broiler chickens in the tropics

OBJECTIVE

Microencapsulation is a technique to improve stability, bioavailability, and controlled release of active ingredients at a target site. This experiment aimed to investigate the effects of microencapsulated basil oil (MBO) on growth performance, apparent ileal digestibility (AID), jejunal histomorphology, bacterial population as well as antioxidant capacity of broiler chickens in a tropical climate.

METHODS

A total of 288 one-day-old female broilers (Ross 308) were randomly allocated into 4 groups (6 replicates of 12 birds), based on a completely randomized design. Dietary treatments were as follows: i) basal diet (NC), ii) basal diet with avilamycin at 10 ppm (PC), iii) basal diet with free basil oil (FBO) at 500 ppm, and iv) basal diet with MBO at 500 ppm, respectively.

RESULTS

Dietary supplementation of MBO improved average daily gain, and feed conversion ratio of broilers throughout the 42-d trial period (p<0.05), whereas MBO did not affect average daily feed intake compared with NC group. The broilers fed MBO diet exhibited a greater AID of crude protein and gross energy compared with those in other groups (p<0.05). Lactobacillus spp. and Escherichia coli populations were not affected by feeding dietary treatments. Both FBO and MBO had positive effects on jejunal villus height (VH), villus height to crypt depth ratio (VH:CD) and villus surface area of broilers compared to NC and PC groups (p<0.05). Superoxide dismutase level in the duodenal mucosa of MBO group was significantly increased (p<0.01), whereas malondialdehyde level was significantly decreased (p<0.01).

CONCLUSION

Microencapsulation could be considered as a promising driver of the basil oil efficiency, consequently MBO at 500 ppm could be potentially used as a feed additive for improvement of intestinal integrity and nutrient utilization, leading to better performance of broiler chickens.

Effects of dietary supplementation with Artemisia argyi alcohol extract on growth performance, blood biochemical properties and small intestinal immune markers of broilers challenged with lipopolysaccharide

ContextBroilers are prone to immunological stress when subjected to unsuitable environmental conditions (such as virus attack, nutrient deficiency and high stocking density), lowering immunity and resulting in inflammatory bowel diseases. The herb-feed additive Artemisia argyi has been applied in poultry production, and its extract may improve small intestinal immune capacity.AimsThis study was conducted to investigate the effect of A. argyi alcohol extract (AAAE) on growth performance and blood biochemical and small intestinal immune markers of broilers challenged with a proinflammatory substance, lipopolysaccharide (LPS). The study also examined possible mechanisms of action, and aimed to clarify whether AAAE could be applied as a feed additive.MethodsIn total, 192 one-day-old Arbor Acres broilers were allocated to four groups following a 2×2 factorial arrangement (including six replicates with eight birds per replicate) with two dietary AAAE rates (0 or 750mg/kg) and two immune stress treatments (LPS or saline injection). Blood and small intestine were sampled on Days21 and 35.Key resultsDietary AAAE alleviated the LPS-induced decrease in bodyweight, average daily gain and average daily feed intake, and mitigated the elevated serum alanine aminotransferase, triglyceride, low-density lipoprotein cholesterol, adrenocorticotropic hormone and corticosterone concentrations at Day21 and/or Day35 in LPS-challenged broilers. AAAE significantly (P&lt;0.05) attenuated LPS-induced increases in intestinal immunoglobulin (IgA, IgG and IgM) and interleukin (IL-1β and IL-6) concentrations. Moreover, the small intestinal mRNA abundances of the genes TLR4, MyD88, NF-κBp65, IL-1β and IL-6 in LPS-challenged broilers were decreased (P&lt;0.05) in response to dietary AAAE treatment.ConclusionsThese results further demonstrated that AAAE at 750mg/kg enhanced small intestinal tissue immune capacity of broilers, thereby alleviating LPS-induced immune stress damage in broilers. Its mechanism of action may be related to the mediating of TLR4/NF-κB pathways.ImplicationsDietary AAAE can be used to improve the immune function of broilers, and to provide a new scientific theoretical basis for the development of new anti-stress feed additives.

Betaine improves growth performance, liver health, antioxidant status, breast meat yield, and quality in broilers fed a mold-contaminated corn-based diet

Betaine has been demonstrated to improve growth performance and antioxidant status of animals under various stress conditions. However, there is no literature on the effects of betaine in animals exposed to mycotoxins, which are among the most prevalent contaminants in feed. Therefore, this study was conducted to evaluate the influence of dietary betaine on broilers fed a diet based on mold-contaminated corn (MCC). A total of 192 Ross 308 male broiler chicks at 1 d of age were randomly divided into 4 groups with 6 replicates and fed an MCC-based diet supplemented with 0, 250, 500, and 1,000 mg/kg betaine, respectively. Betaine increased average daily gain (linear, P = 0.030) and decreased feed conversion ratio (linear, P = 0.027) of broilers during d 1 – 21, and decreased feed conversion ratio during d 22 – 42 (linear, P = 0.012; quadratic, P < 0.001) and d 1 – 42 (linear, P = 0.003; quadratic, P = 0.004), whereas feed intake was not affected. Total cholesterol (linear, P = 0.024), alanine aminotransferase (quadratic, P < 0.001) and alkaline phosphatase (linear, P = 0.007; quadratic, P = 0.025) activities in serum were decreased by betaine. Betaine linearly increased breast muscle yield (P = 0.003) and pH_24 h (P = 0.008), and decreased drip loss (P = 0.022). Betaine increased (linear, P = 0.025; quadratic, P = 0.016) total superoxide dismutase activity in breast muscle and reduced malondialdehyde content in serum (linear, P = 0.006), liver (quadratic, P = 0.006) and breast muscle (linear, P = 0.003). Moreover, the zearalenone concentrations in breast muscle were linearly decreased by betaine (P = 0.006). It was concluded that betaine could improve growth performance, liver health, antioxidant status, and breast meat yield and quality, and reduce zearalenone residue in broilers fed the MCC-based diet, especially at 500 or 1,000 mg/kg.

Blue-Green Algae (Spirulina platensis) Alleviates the Negative Impact of Heat Stress on Broiler Production Performance and Redox Status

Simple Summary

Heat stress is the leading cause of poor broiler productivity in tropical and subtropical countries. To face such stress, natural antioxidant feed additives are attracting interest due to their high effectiveness and safety. Dietary algae Spirulina platensis have received much attention in the last decade due to its high protein content. The effectiveness of (Spirulina platensis) as a feed additive to alleviate the negative impacts of heat stress on production performance was investigated. Under heat stress conditions, Spirulina supplementation improved broiler productivity and was able to bring back redox balance. It can be inferred that Spirulina can be used as a natural antioxidant supplementation to heat-stressed broilers for improving the production performance and modulating serum metabolites to bring them to the normal values.

Abstract

The modern broiler industry faces huge challenges to keep high production quality and quantity, especially under environmental heat stress conditions. The negative effect of heat stress on broiler productivity is mediated by oxidative stress induction. The blue-green alga (Spirulina platensis) has many applications in poultry nutrition with the high levels of bioactive antioxidant compounds, which can alleviate the oxidative stress damage induced by high ambient temperature. The current study was designed to investigate the effects of dietary Spirulina inclusion at different levels on growth performance, redox status, carcass traits, meat quality, blood hematology, and metabolites profile of broilers subjected to cyclic heat stress. A total of 300 one-day-old Cobb-500 broiler chicks were recruited. Starting from day 21 to 42 of age, birds were randomly divided into five treatment groups with 6 replicates × 10 birds per group, where the first one was provided with the basal diet and reared under normal thermal conditions (23 ± 1 °C) to serve as a negative control. Meanwhile, the other four groups were exposed to cyclic heat stress (34 ± 1 °C for 8 h per day) and were fed a basal diet supplemented with Spirulina at a concentration of 0, 0.5, 1 or 1.5%. Spirulina supplementation to heat-stressed broilers was able to alleviate the negative impacts of heat stress on the final average daily gain, body weight and feed conversion ratio, with the best impact observed among the chickens fed 1% Spirulina. Hematological results indicate increasing hemoglobin and hematocrit levels with Spirulina supplementation compared to the non-supplemented stressed group. Further, Spirulina supplementation significantly influenced blood lipid metabolites marked by reduced serum cholesterol and low-density lipoprotein (LDL), and increased high-density lipoprotein (HDL) levels. The lipid peroxidation level was reduced (p < 0.05), while the antioxidant enzyme activity was increased with Spirulina supplementation to the heat-stressed group. Spirulina supplementation at 0.5 or 1% improved carcass dressing, breast and leg percentages. It can be concluded that dietary Spirulina supplementation at 0.5 or 1% to broiler reared under heat stress conditions can effectively improve broiler production performance and balance the redox status.

A recent update on the multifaceted health benefits associated with ginger and its bioactive components

Due to recent lifestyle shifts and health discernments among consumers, synthetic drugs are facing the challenge of controlling disease development and progression. Various medicinal plants and their constituents are recognized for their imminent role in disease management via modulation of biological activities. At present, research scholars have diverted their attention on natural bioactive entities with health-boosting perception to combat the lifestyle-related disarrays. In particular, Zingiber officinale is a medicinal herb that has been commonly used in food and pharmaceutical products. Its detailed chemical composition and high value-added active components have been extensively studied. In this review, we have summarized the pharmacological potential of this well-endowed chemo preventive agent. It was revealed that its functionalities are attributed to several inherent chemical constituents, including 6-gingerol, 8-gingerol, 10-gingerol, 6-shogaol, 6-hydroshogaol, and oleoresin, which were established through many studies (in vitro, in vivo, and cell lines). In this review, we also focused on the therapeutic effects of ginger and its constituents for their effective antioxidant properties. Their consumption may reduce or delay the progression of related diseases, such as cancer, diabetes, and obesity, via modulation of genetic and metabolic activities. The updated data could elucidate the relationship of the extraction processes with the constituents and biological manifestations. We have collated the current knowledge (including the latest clinical data) about the bioactive compounds and bioactivities of ginger. Their detailed mechanisms, which can lay foundation for their food and medical applications are also discussed.

Chitosan oligosaccharide as an effective feed additive to maintain growth performance, meat quality, muscle glycolytic metabolism, and oxidative status in yellow-feather broilers under heat stress

This study investigated the effects of dietary chitosan oligosaccharides (COS) supplementation on growth performance; corticosterone, growth hormone, and insulin-like growth factor-1 concentration; relative organ weight; liver function; meat quality; muscle glycolytic metabolism; and oxidative status in yellow-feather broilers under heat stress. A total of 108 35-day-old Chinese yellow-feather broilers (BW, 470.31 ± 13.15 g) was randomly allocated to 3 dietary treatments as follow: control group, basal diet and raised under normal temperature (24°C); HS group, basal diet and raised under cycle heat stress (34°C from 10:00 to 18:00 and 24°C for the rest time); and HSC group, basal diet with 200 mg/kg COS supplementation and raised under cycle heat stress. Each treatment had 6 replication pens and 6 broilers per pen. Results indicated that heat stress decreased ADG, ADFI, gain:feed ratio, the relative weight of thymus, bursa of Fabricius, pancreas, proventriculus, gizzard, and liver, growth hormone concentration, pH_24h, muscle glycogen content, muscle superoxide dismutase and glutathione peroxidase activity, as well as increased corticosterone, alanine aminotransferase and aspartate aminotransferase level, cooking loss, muscle lactate and malondialdehyde content. Compared with the HS group, broilers in the HSC group had higher ADG, the relative weight of thymus, bursa of Fabricius, and liver, growth hormone concentration, pH_24h, muscle glycogen content, muscle superoxide dismutase and glutathione peroxidase activity, and lower serum corticosterone, alanine aminotransferase and aspartate aminotransferase level, cooking loss, and muscle lactate and malondialdehyde content. In conclusion, the results suggested that COS could be used as an effective feed additive to maintain growth performance, liver function, meat quality, muscle glycolytic metabolism, and oxidative status of yellow-feather broilers under heat stress. The improved meat quality is possibly through reducing muscle glycolysis metabolism and improving muscle oxidative status by dietary COS supplementation in broilers under heat stress.