Dietary Chitosan Oligosaccharides Research Articles

Effects of dietary Chitosan oligosaccharides supplementation on Th17/Treg balance and gut microbiota of early weaned pigeon squabs

Our previous study found that early weaning is associated with decreased growth performance, intestinal barrier impairment, and an imbalance in Th17/Treg in pigeon squabs. Chitosan oligosaccharides (COS) has been substantiated to regulate gut microbiota and restore Th17/Treg equilibrium in mammals, thereby ameliorating growth performance. However, the potential effects of COS in altricial birds remain unclear. Three hundred healthy 7-day-old American king pigeon squabs were selected with similar body weights and randomly divided into 5 groups. The 5 treatment groups were as follows: the control group (CON), fed with artificial pigeon milk; 4 supplementation groups, fed with artificial pigeon milk +100 (COS1), 150 (COS2), 200 (COS3), and 250 (COS4) mg/kg COS, respectively. Results showed that dietary supplementation of COS significantly enhanced the growth performance of weaned squabs. Compared to the CON group, the COS groups exhibited increased villus length and villus area in the jejunum and ileum, accompanied by improvements in morphological structure and mucosal permeability. COS was found to reduce the levels of Th17-associated cytokines and increase the levels of Treg-associated cytokines. COS downregulated the expression of retinoic acid receptor-related orphan receptor C (RORC), a key transcription factor of Th17 cells, while upregulated the expression of Forkhead box protein P3 (FOXP3), a key transcription factor of Treg cells. Dietary COS supplementation increased gut bacterial diversity, altered the relative abundance of several bacteria taxa and enhanced the concentration of short-chain fatty acids (SCFA). Correlation analysis demonstrated a close association between gut microbiota, SCFAs, and indicators related to the Th17/Treg balance. Moreover, we found that SCFAs correlated more strongly with Th17/Treg-related indexes than gut microbiota. These results demonstrated that COS could relieve early weaning stress in pigeon squabs and the optimal dosage of dietary COS supplementation was suggested to be 200 mg/kg. In addition, COS had a protective effect on maintaining intestinal immune balance by modulating microbiota and Th17/Treg related signaling pathways, in which SCFAs might play a crucial role as messengers.

In Vitro Evaluation of Chito-Oligosaccharides on Disappearance Rate of Nutrients, Rumen Fermentation Parameters, and Micro-Flora of Beef Cattle.

The study aimed to investigate the effect of dietary chitosan oligosaccharides (COS) meal levels on the nutrient disappearance rate, rumen fermentation, and microflora of beef cattle in vitro. A total of 24 fermentation tanks were randomly divided into four treatments containing 0% COS (CON), 0.02% COS, 0.04% COS, and 0.08% COS for an 8-day experiment period, with each treatment comprising six replicates. The disappear rates of DM, CP, EE, and total gas production were quadratically increased with increasing COS levels. The disappear rates of DM, CP, EE, and ADF were greatest, whereas the total gas production was lowest in the 0.08% COS group. The pH, NH3-N, MCP, the content of propionate, isobutyrate, butyrate, valerate, and the A/P were quadratically increased with increasing COS levels, while the A/P were linearly decreased. The pH, MCP, and the content of propionate, and butyrate were highest, whereas the NH3-N and the content of acetate, isobutyrate, valerate, and the A/P were lowest in the 0.08% COS group. Microbiomics analysis showed that the rumen microbial diversity was not altered between the CON and the 0.08% COS group. However, the relative abundance of Methanosphaera, Ruminococcus, Endomicrobium, and Eubacterium groups was increased, and the relative abundance of pathogenic bacteria Dorea and Escherichia-Shigella showed a decrease in the 0.08% COS group. Overall, the 0.08% COS was the most effective among the three addition levels, resulting in an increase in the disappearance rate of in vitro fermented nutrients and improvements in rumen fermentation indexes and microbial communities. This, in turn, led to the maintenance of rumen health.

Influence of dietary chitosan-oligosaccharides supplementation on productive and reproductive performance of laying hens

Abstract This experiment aimed to ascertain whether adding chitosan-oligosaccharides (COS) to the diet will affect Mandarah laying hens’ productivity and reproductive efficiency. At the age of 34 weeks, 120 laying hens and 12 cocks of the Mandarah chicken strain were separated into four groups, each consisting of 30 hens and three cocks. The 1st group served as a control group, receiving only a basic diet. The 2nd, 3rd, and 4th experimental groups received 0.1, 0.2, and 0.5 g/kg of chitosan-oligosaccharides as an addition to the base diet, respectively. According to the findings of this study, the majority of the analyzed attributes differed significantly between treatment groups. Comparing the COS-treated birds to the control birds, the COS-treated birds significantly increased egg production, improved feed conversion, Haugh unit score, shell thickness, fertility, hatchability, ovary weight, and the number of yellow ovarian follicles as well as blood estradiol-17β (E2) and testosterone concentrations. Furthermore, compared to the other treated groups, introducing COS at a level of 0.1 g/kg diet resulted in the best laying rate, egg mass, and feed conversion. The highest percentage of fertility, hatchability of hatching eggs, ovary weight, number of yellow ovarian follicles, and serum E2 concentration was also found in birds fed COS at a dose of 0.2 g/kg feed. In addition, compared to the control diet, COS treatment at 0.1, 0.2, and 0.5 g/kg enhanced relative economic efficiency by 464.43, 457.41, and 352.75%, respectively. It is concluded that chitosan improves economic efficiency, reproductive performance, productivity in laying hens, and overall health when used at 0.1 g/kg diet.

Chitosan oligosaccharides as dietary antioxidants in nutrition of broiler chickens

Chitosan oligosaccharides (COS) have attracted considerable attention in poultry research due to their diverse biological activities and possible effects on the welfare and productivity of broiler chickens. A thorough examination of many studies indicates that the influence of COS on indices such as antioxidative functions, growth performance, immunological responses, and metabolic implications in broilers is significant. For example, specific dosage levels of COS have significantly enhanced antioxidant activity, regulation of cholesterol levels, and improved growth performance. The research findings have provided evidence for COS's antioxidative and anti-inflammatory properties and its capacity to mitigate the effects caused by stress. Nevertheless, the effectiveness of reactions might be influenced by the dosage and may demonstrate variances. Broiler chickens are suggested to consume dietary COS levels between 350 mg/kg and 500 mg/kg feed to obtain antioxidant and immunological advantages. Nevertheless, the most favorable results regarding growth and the ability to absorb nutrients are typically found when the intake ranges from 0.5 g/kg to 1.0 g/kg feed. For yellow-feather broilers experiencing heat stress, it is advisable to administer a dosage of 200 mg/kg feed of COS. However, it is essential to closely observe dosages exceeding 2.5 g/kg since they may significantly impair growth performance. The diverse research on using COS in broiler management has provided valuable insights into its intricate nature. This review has highlighted the potential benefits of COS in enhancing chicken health and nutrition. However, it has also underscored the need for additional research to optimize its effectiveness in broiler production fully. It can be concluded that dietary COS in broiler chickens in doses ranging from 200 mg to 1000 mg/kg feed has a positive effect on growth performance, antioxidative properties, regulation of lipid metabolism, ability to mitigate stress, impact on meat quality, and carcass traits, but exceeding 2.5 g/kg feed may significantly impair in growth performance in the broiler.

Dietary Chitosan Oligosaccharide Supplementation Improves Meat Quality by Improving Antioxidant Capacity and Fiber Characteristics in the Thigh Muscle of Broilers.

This study investigated the effects of dietary chitosan oligosaccharide (COS) supplementation on meat quality, antioxidant capacity, and muscle fiber characteristics in the thigh muscle of broilers. The results showed that dietary COS supplementation decreased shear force and increased crude protein content and nutritional value in the thigh muscle, while decreasing the content of C16:0, C18:0, and total saturated fatty acids. Dietary COS supplementation increased free radical scavenging activity, antioxidant enzyme activity, and antioxidant enzyme-related gene expression. Additionally, COS promoted MyHCI while decreasing MyHCIIb mRNA expression levels. The myofiber transformation was associated with upregulated gene expression of CaN, NFATc1, MyoD, and SIRT1. Together, the results of this study demonstrate that dietary COS supplementation improves meat quality, nutritional value, antioxidant capacity, and myofiber transformation to more oxidative muscle fibers in the thigh muscle of broilers when its supplemental level is 400 mg/kg.

Effects of dietary chitosan oligosaccharide on the growth, intestinal microbiota and immunity of juvenile red claw crayfish (Cherax quadricarinatus)

This study aimed to evaluate the potential benefits of chitosan oligosaccharide (COS) on red claw crayfish (Cherax quadricarinatus) and explore its underlying mechanisms. The crayfish were randomly divided into six groups, and the diets were supplemented with COS at levels of 0 (C0), 0.2 (C1), 0.4 (C2), 0.6 (C3), 0.8 (C4), and 1 (C5) g kg−1. Treatment with COS significantly improved the growth performance of the crayfish with a higher weight gain rate (WGR) and specific growth rate (SGR) in the C2 group compared to the C0 group. Additionally, the content of crude protein in the crayfish muscles in the C1 group was significantly higher than that of the C0 group. Regarding non-specific immunity, the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and alkaline phosphatase (AKP), and the levels of expression of the genes related to immunity (SOD; anti-lipopolysaccharide factor [ALF]; thioredoxin1 [Trx1]; C-type lysozyme, [C-LZM]; and GSH-Px) in the hepatopancreas and hemolymph increased significantly (P < 0.05) after supplementation with 0.4 g kg−1 of COS, while the content of malondialdehyde (MDA) decreased (P < 0.05). The survival rate of C. quadricarinatus increased (P < 0.05) in the C2, C3, C4, and C5 groups after the challenge with Aeromonas hydrophila. This study found that COS has the potential to modulate the composition of the intestinal microbiota and significantly reduce the abundance of species of the phylum Proteobacteria and the genera Aeromonas and Vibrio in the gut of C. quadricarinatus, while the abundance of bacteria in the phylum Firmicutes and the genus Candidatus_Hepatoplasma improved significantly. This study suggests that the inclusion of COS in the diet of C. quadricarinatus can enhance growth, boost immunity, and increase resistance to infection with A. hydrophila, especially when supplemented at 0.4–0.8 g kg−1.

Chitosan oligosaccharide improves intestinal function by promoting intestinal development, alleviating intestinal inflammatory response, and enhancing antioxidant capacity in broilers aged d 1 to 14

This study was conducted to investigate the effects of chitosan oligosaccharide (COS) supplementation on intestinal development and functions, inflammatory response, antioxidant capacity and the related signaling pathways in broilers aged d 1 to 14. A total of 240 one-day old male Arbor Acres broilers (40.47 ± 0.30 g) were randomly allotted to 4 groups, and each group consisted of 6 replicate pens with 10 broilers per replicate. Broilers fed a basal diet supplementation with COS at 0 (CON group), 200 (COS200 group), 400 (COS400 group), and 800 mg/kg (COS800 group) for 14 d, respectively. Broilers in the COS supplementation groups had no significant effects on growth performance. Compared to the CON group, dietary COS supplementation increased (P < 0.05) the relative weight of duodenum, jejunal lipase activity, duodenal and ileal villus surface area, and lower (P < 0.05) ileal amylase and alkaline phosphatase activity, and crypt depth. The expression level of duodenal glucose transporter 1 (GLUT1), Na+-glucose cotransporter 1 (SGLT1), peptide transporter 1 (PepT1), occludin, zonula occludens-1 (ZO-1), toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and interleukin-10 (IL-10), jejunal SGLT1, PepT1, occludin, tumor necrosis factor-α (TNF-α), and ileal SGLT1, PepT1, and fatty acid binding protein 1 (FABP1) was upregulated by COS. However, the expression level of duodenal FABP1 and TNF-α, jejunal GLUT1, ZO-1, TLR4, MyD88, nuclear factor kappa-B p65 (NF-κB p65), and IL-1β, and ileal GLUT1, NF-κB p65, and IL-1β was downregulated by COS. Furthermore, dietary COS supplementation increased duodenal catalase (CAT), glutathione peroxidase (GSH-Px), and total superoxide dismutase (T-SOD) activity, jejunal CAT and T-SOD activity, upregulated the expression level of duodenal nuclear factor-erythroid 2-related factor 2 (Nrf2), CAT, glutathione peroxidase 1 (GPX1), and copper and zinc superoxide dismutase (Cu/Zn SOD), jejunal CAT, and ileal Nrf2, CAT, and GPX1. These results suggested that COS could promote intestinal development and functions in broilers aged d 1 to 14, which might be mediated by alleviating intestinal inflammatory response and enhancing antioxidant capacity.

Chitosan oligosaccharides in the diet of broiler chickens under cold stress had anti-oxidant and anti-inflammatory effects and improved hematological and biochemical indices, cardiac index, and growth performance

This experiment was conducted to investigate the effect of dietary chitosan oligosaccharide (COS) on broiler chickens under cold stress. A total of 500 one -day-old male broiler chickens were randomly allocated into five treatments with five replicate pens (with 20 broiler chickens per pen). The broiler chickens in thermoneutral treatment (TN control) were reared at normal temperature, while the broiler chickens in other four treatments were subjected to the cold stress (CS) + 0, 1, 2, and 3 g COS/kg. At d 42, two broiler chickens per cage were weighed and euthanized, and samples for blood and heart were collected. Dietary COS improved growth performance indices and reduced relative heart weight, right ventricle to total ventricle ratio, right ventricle to body weight, and mortality (P < 0.01). The activities of superoxide dismutase, catalase, and glutathione peroxidase in serum and liver were increased, and malondialdehyde was reduced by COS supplementation compared to the CS treatment (P < 0.01). The cold stress-induced effect on serum and liver levels of TNF-α and interleukin-1β were reduced, and interleukin-10 was increased by dietary COS supplementation (P < 0.01). Moreover, supplementing of diets with COS alleviated the adverse effect of cold stress as reflected by a reduction in alanine transaminase, aspartate transaminase, alkaline phosphatase, triglyceride, and cholesterol compared to the CS treatment (P < 0.01). It is also, the red blood cell count, hemoglobin, hematocrit, heterophil, and heterophil to lymphocyte ratio reduced by COS supplementation compared to the CS treatment . In conclusion, COS supplementation during cold stress may be used to alleviate cold stress related changes in broiler chickens.

Chitosan Oligosaccharides Alleviate Heat-Stress-Induced Lipid Metabolism Disorders by Suppressing the Oxidative Stress and Inflammatory Response in the Liver of Broilers.

Heat stress has been reported to induce hepatic oxidative stress and alter lipid metabolism and fat deposition in broilers. Chitosan oligosaccharides (COSs), a natural oligosaccharide, has anti-oxidant, anti-inflammatory, and lipid-lowering effects. This study is conducted to evaluate dietary COS supplementation on hepatic anti-oxidant capacity, inflammatory response, and lipid metabolism in heat-stressed broilers. The results indicate that heat-stress-induced poor (p < 0.05) growth performance and higher (p < 0.05) abdominal adiposity are alleviated by COS supplementation. Heat stress increases (p < 0.05) serum AST and ATL activity, serum and liver MDA, TG, TC, and LDL-C levels, and the expression of hepatic IL-1β, IL-6, SREBP-1c, ACC, and FAS, while it decreases (p < 0.05) serum SOD and CAT activity, liver GSH-Px and SOD activity, and the expression of hepatic Nrf2, GPX1, IL-10, MTTP, PPARα, and CPT1. Nevertheless, COS supplementation decreases (p < 0.05) serum AST and ATL activity, serum and liver MDA, TG, TC, and LDL-C levels, and the expression of hepatic IL-1β, IL-6, SREBP-1c, ACC, and FAS, while it increases (p < 0.05) serum SOD and CAT activity, liver GSH-Px activity, and the expression of hepatic Nrf2, CAT, IL-10, LPL, MTTP, PPARα, and CPT1. In conclusion, COS could alleviate heat-stress-induced lipid metabolism disorders by enhancing hepatic anti-oxidant and anti-inflammatory capacity.

Effects of dietary chitosan oligosaccharides supplementation on meat quality, chemical composition and anti-oxidant capacity in frizzled chickens

The aim of this study was to evaluate dietary chitosan oligosaccharides (COS) supplementation on meat quality, chemical composition and oxidative stability in frizzled chickens. A total of 360 one-day-old female frizzled chickens with an average body weight of 34.38 ± 1.23 g were randomly allocated to four groups with six replications (10 chickens/replication) in this 84-day experiment. The chickens in the control group (CON) fed the basal diet and the other three experimental diets were based on the basal diet with 300, 600 and 900 mg/kg COS supplementation, respectively. The results indicated that dietary COS increased growth performance, eviscerated and breast muscle yield while decreased abdominal fat yield, accompanied with increasing pH45min, pH24h, Lightness, drip loss and cooking loss in breast and thigh muscle. The scavenging activity of 2,2-diphenyl-1-picrylhydrazyl, superoxide radical, hydroxyl radical and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt, the activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) in breast and thigh muscle were improved by COS while malondialdehyde content was decreased. COS up-regulated the gene expression of nuclear factor erythroid 2-related factor 2, heme oxygenase-1, NAD(P)H quinone dehydrogenase 1, SOD, CAT and GSH-Px in breast and thigh muscle. In conclusion, dietary COS supplementation improved meat quality by improving pH, colour, water holding capacity and anti-oxidant capacity, accompanied with decreased lipid metabolism in frizzled chickens. Dietary 600 mg/kg COS was recommended in frizzled chickens’ diet to improve meat quality. Highlights COS improves growth performance of frizzled chickens. COS improves meat quality of frizzled chickens. COS enhances anti-oxidant capacity of frizzled chickens’ meat.

Immune response, hematological traits, biochemical blood parameters, and histological status of laying hens influenced by dietary chitosan-oligosaccharides

This experiment aimed to examine the effect of chitosan-oligosaccharides (COS) supplementation in laying hens' diets affected their immune response, hematological characteristics, blood biochemical parameters, and histological status. At the age of 34 wk, 200 laying hens and 20 cocks of the Mandarah chicken strain were allotted into four groups, each consisting of 50 hens and five cocks. The first group acted as a control group, fed on a basal diet. The second, third, and fourth experimental groups each received 0.1, 0.2, and 0.5 g/kg of COS in addition to a base diet. Birds received COS at various dosages had significantly (P ˂ 0.05) increased serum concentration of immunoglobulins, avian influenza, and Newcastle disease antibodies compared with the control birds. Moreover, adding COS at level 0.2 g/kg diet insignificantly enhanced immune response than the rest of the treatment groups. Also, treated birds with COS at different levels had insignificantly improved hematological parameters such as red blood cells, white blood cells, hemoglobin and hematocrit compared to the control group. Birds fed COS at all levels had significantly decreased serum cholesterol, triglycerides, Ca++ and alanine aminotransferase concentrations compared with control birds. In addition, compared to the control group, chitosan-treated birds showed enhanced histological examination of the small intestine, isthmus, and testis, notably in birds given COS at 0.1 g/kg diet compared to other treated birds. Cocks fed COS at all levels improved testicular tissues and increased the number and diameter of seminiferous tubules compared with control birds Morphological examination of the ileum showed increased villi number, height, and crypt depth. It is possible to conclude that laying hens' physiological performance and general health can be effectively improved by using chitosan at 0.1 or 2 g/kg diet levels enhanced immune response.

Effects of Chitosan Oligosaccharide on Production Performance, Egg Quality and Ovarian Function in Laying Hens with Fatty Liver Syndrome.

Simple SummaryFatty liver syndrome (FLS) often occurs in caged laying hens and can cause decreases in production performance. Chitosan oligosaccharide (COS), degraded from chitin or chitosan, has been demonstrated to prevent metabolic diseases in rodents. In this work, we found that dietary COS supplementation could improve production performance and egg quality in laying hens with FLS. Further study indicated that improved ovarian morphology and function may be involved in these beneficial effects of COS. Specifically, dietary COS supplementation decreased oxidative stress, inflammation and apoptosis in the ovaries of laying hens with FLS. This study provides evidence for the application of COS to improve production performance and egg quality in laying hens with FLS.This study aimed to investigate the role of chitosan oligosaccharide (COS) as an additive in the feed of laying hens with fatty liver syndrome (FLS). Effects on production performance, egg quality as well as ovarian function were determined. A total of 360 Lohmann Pink-shell laying hens (28 weeks old) were randomly assigned to 5 groups (6 replicates × 12 birds). Hens were fed with a basal diet and a high-energy low-protein (HELP) diet supplemented with 0, 200, 400 and 800 mg/kg COS. COS reversed the lowered laying rates, increased feed-to-egg ratios and decreased albumen heights and Haugh units induced by the HELP diet. Additionally, COS improved the ovarian morphologies damaged by the HELP diet. Furthermore, COS enhanced antioxidant enzyme activities, reduced malonaldehyde levels and downregulated the mRNA expressions of nuclear factor kappa B, pro-inflammation cytokine genes and pro-apoptosis-related genes, while it upregulated the mRNA expression of anti-apoptosis-related genes in the ovaries of HELP-diet-fed hens. These findings suggested that dietary COS supplementation could improve production performance and egg quality in laying hens with FLS, and these beneficial effects were linked to improved ovarian morphology, which was attributed to decreased oxidative stress, inflammation and apoptosis in the ovaries.

Dietary chitosan oligosaccharides improves health status in broilers for safe poultry meat production

Feed additives are routinely used for improving poultry health and production worldwide. Chitosan oligosaccharides (COS) is a relatively new feed additive that is a derivative of chitosan, a non-toxic linear polysaccharide with many biological functions. To investigate the efficacy of COS on gut morphology and serum biochemical profile (lipid, protein, glucose, creatinine and enzymes), a total of 180 day-old broiler chicks (n = 45) were allocated into allocated to 1 of 4 groups: control (T0) and treatment groups (T1, T2 and T3) fed basal diet supplemented with increasing amounts of COS for 35 days. Our findings showed that dietary COS supplementation had positive effects on the body weight and body weight gain in the treatment groups. Villus height and width, ratio of villus height and crypts depth, and tunica mucosa thickness of duodenum increased (P > 0.05) in the treatment groups (T1 and T2), whereas crypts depth of duodenum and cecum were decreased in the treatment groups (T1 and T2) compared to the control group; treatment group 3 (T3), however, was almost similar to the control group. In the case of cecum, tunica mucosa thickness, length and width of mucosal folds showed similar results as duodenum. The population and size of intestinal glands and lymphocytic infiltration in the mucosa were increased considerably in the treatment groups (T1 and T2) than control group. Total serum cholesterol, triglyceride, LDL and VLDL cholesterol levels were significantly lowered in the treatment group 2 (T2) than control group or other COS treated groups (P < 0.05), although HDL cholesterol level was significantly (P < 0.05) higher in all of the treatment groups, but substantially higher in the group treatment groups 1 and 3 (T1 and T3) compared to control group. Total serum protein, albumin, and globulin were gradually increased in all of the treatment groups along with the increasing dose rates. The liver and kidney functions (ALT, AST and creatinine) were not significantly (P > 0.05) affected due to COS supplementation. These results suggest that COS has a dose-dependent response to improve gut morphology and health physiology in broilers; low to medium doses are more favorable for safe poultry production as it enhances growth performance, increases villus surface area, reduces undesirable cholesterols and positively affects the blood glucose and protein levels. These results would be helpful in exploring the efficacy of COS as a potential feed additive for safe poultry meat production, which is a time-demanding issue for the poultry industry from the consumers' point of view.

Chitosan oligosaccharides alleviate acute heat stress-induced oxidative damage by activating ERK1/2-mediated HO-1 and GSH-Px gene expression in breast muscle of broilers

The purpose of this study was to evaluate the effects of chitosan oligosaccharides (COS) on acute heat stress (AHS) induced poor meat quality by alleviating oxidative damage through mitogen-activated protein kinase-nuclear factor-erythroid 2-related factor 2-antioxidant responsive element (MAPK-Nrf2-ARE) signaling pathway. A total of 108 thirty-five-day-old Chinese indigenous broilers (Luhua chicken) was used for this 42-d experiment. The broilers were randomly allocated to 3 treatments: control group (CON), AHS group, and AHS with 400 mg/kg COS supplementation (AHS-C) group. Both CON and AHS groups given the basal diet, and the AHS-C group given the basal diet with 400 mg/kg COS supplementation. On d 42, broilers in the AHS and AHS-C groups treated with AHS (increasing temperature from 24 to 34°C in 2-h and held for another 2-h), and the CON group under normal temperature (24°C). AHS exposure elevated (P < 0.05) body temperature (rectal, comb, eyelids, and feet) of broilers, increased (P < 0.05) breast muscle lightness (L*), drip loss, share force, hydrogen peroxide (H2O2) scavenging activity, reactive oxygen species (ROS) production, malondialdehyde (MDA) content, and catalase (CAT) activity, however, decreased (P < 0.05) pH45min, pH24h, redness (a*), and relative expression of heme oxygenase-1 (HO-1). Compared to the AHS group, dietary COS supplementation increased (P < 0.05) breast muscle pH45min, pH24h, and a*, H2O2 scavenging activity, as well as relative expression of HO-1 and glutathione peroxidase (GSH-Px), however, decreased (P < 0.05) drip loss, share force, superoxide anion free radicals (O2•−) scavenging activity, ROS production, and MDA content. It was concluded that AHS impaired meat quality, which may be related to oxidative damage, as evidenced by increasing ROS production, MDA content, and decreasing the relative expression of HO-1. Dietary COS supplementation could effectively elevate the meat quality of broilers exposed to AHS via decreasing ROS production, activating the Nrf2 pathway, and Nrf2-mediated HO-1 and GSH-Px gene expression.

Supplementing Chitosan Oligosaccharide Positively Affects Hybrid Grouper (Epinephelus fuscoguttatus ♀ × E. lanceolatus ♂) Fed Dietary Fish Meal Replacement With Cottonseed Protein Concentrate: Effects on Growth, Gut Microbiota, Antioxidant Function and Immune Response

Oligosaccharides have recently received much attention from researchers owing to their multiple biological activities. This study was conducted to investigate the effects of a diet with reduced fish meal and chitosan oligosaccharide (COS) supplementation on a hybrid grouper (Epinephelus fuscoguttatus ♀ × E. lanceolatus ♂). Seven isonitrogenous and isolipidic types of diet were formulated to feed the groupers for 56 days. To prepare the feed, a reference diet (FM group) containing 55% fish meal was used. Concentrated cottonseed protein (CPC) was used to replace 45% of the fish meal protein, and different COS supplementation levels (0, 0.2%, 0.4, 0.6, 0.8, and 1%) were added. After an 8-week breeding trial, Vibrio harveyi bacteria were injected into the groupers for a 7-day challenge test. The results showed that the FM and COS0.4 groups showed the best growth performance among the groups (p &amp;lt; 0.05); however, there was no significant difference in the survival rate (p &amp;gt; 0.05). Unlike in the FM group, adhesion and breakage of the intestinal plica occurred in the COS0 group. The height and width of the gut fold reached maximum values in the COS0.4 group (p &amp;lt; 0.05). Microbiome sequencing suggested that there was a stable microbiota core in the gut of the groupers. With increasing COS levels, the abundance of both beneficial bacteria and conditional pathogens increased; the activities of serum glucose oxidase, catalase, and total superoxide dismutase also increased (p &amp;lt; 0.05). In the gut tissue, the activities of glutathione peroxidase, glutathione reductase, and glutamine increased first but then decreased (p &amp;lt; 0.05); the contents of lysozyme, acid phosphatase, complements C3 and C4, and IgM showed upward trends (p &amp;lt; 0.05). Compared with that in the FM group, the expression of IL-1β and TNF-α in the COS0 group was upregulated. Gene expression levels of TLR22, TGF-β, and Nrf2 increased first but then decreased with COS supplementation levels (p &amp;lt; 0.05). COS supplementation reduced the cumulative mortality of the groupers in the challenge test (p &amp;lt; 0.05). In general, the results of this study demonstrated that dietary COS supplementation enhanced growth performance, intestinal health, and antioxidant and immune responses of groupers fed with a low-fish meal diet. The optimal and acceptable levels of COS supplement were 0.45 and 0.4–0.6%, respectively; these values can provide a reference for developing aquatic prebiotics.

Effects of chitosan oligosaccharides on meat quality, muscle energy metabolism and anti-oxidant status in broilers that have experienced transport stress

Context Pre-slaughter transport, exposed broilers to various stressors, which resulted in detrimental effects on animal welfare, live bodyweight loss, mortality and meat quality. There was growing interest to explore effective ways to reduce the stress response and improve meat quality of transported broilers by using dietary feed additives. Aims The purpose of the present study was to investigate the effect of chitosan oligosaccharides (COS) on meat quality, muscle energy metabolism and anti-oxidant status of broilers having 3-h transport stress. Methods In total, of 144 35-day-old broilers were randomly allocated to two dietary treatments, including a basal diet (96 broilers), or basal diet supplemented with COS at 200 mg/kg (48 broilers). There were eight broilers per cage, and 12 replication cages in the basal diet group and six replication cages in the basal diet with 200 mg/kg COS group. At the end of the experiment, after a 12-h fast, broilers in the basal diet group were randomly divided into two groups, with six replication cages in each group; then, the broilers were transported as per the following protocols: broilers in the basal diet group (CON group) were without transport stress; broilers in the basal diet group with 3 h of transport stress (TS group), and broilers in the basal diet with 200 mg/kg COS supplementation and 3 h of transport stress (TSC group). The serum corticosterone concentration, serum, liver and muscle anti-oxidant status, as well as meat quality and muscle energy metabolism were analysed. Key results Compared with the CON group, TS group showed increased bodyweight loss, serum corticosterone concentration, breakdown of muscle glycogen, increased muscle lactate dehydrogenase activity, as well as some changes of body anti-oxidant status (higher serum, liver and muscle MDA concentrations, lower serum SOD and GSH-Px, liver SOD and CAT, and lower muscle SOD, GSH-Px, and CAT activity), accompanied with lower pH45min and pH24h. Nevertheless, compared with the TS group, dietary COS supplementation reduced bodyweight loss, decreased muscle MDA concentration, increased muscle SOD and CAT activity, and was accompanied with improving pH24h. Conclusions The results suggested that the positive effects of dietary COS supplementation in maintaining meat quality were mainly due to the improved muscle anti-oxidant status. Implications Dietary supplementation with 200 mg/kg COS could serve as a beneficial and effective way to alleviate transport-impaired meat quality of broilers.

Effects of dietary chitosan oligosaccharides on oxidative stress and inflammation response in liver and spleen of yellow-feather broilers exposed to high ambient temperature

Heat stress jeopardised animal health by inducing oxidative stress and inflammation. This study was done to investigate the effects of chitosan oligosaccharides (COS) on oxidative stress and inflammation response in liver and spleen of yellow-feather broilers under high ambient temperature. A total of 144 35-day-old female Chinese indigenous yellow-feather broilers (body weight 450.21 ± 10.05 g) were randomly allocated into 3 dietary treatments with 6 replication pens, each pen had 8 broilers. The treatments were: Control, basal diet; COS100, basal diet with 100 mg/kg COS; COS200, basal diet with 200 mg/kg COS. During day 22 to 42 (57 to 77 days of age), broilers in the COS200 group had higher (p < .05) ADFI than broilers in the Control group. Broilers in the COS200 group had lower (p < .05) serum alanine aminotransferase, aspartate aminotransferase, and tumour necrosis factor-α levels, and spleen malondialdehyde (MDA) content, but had higher (p < .05) liver superoxide dismutase activity and serum interleukin-10 level than broilers in the Control group. Broilers in the COS100 and COS200 groups had lower (p < .05) serum and liver MDA content, and serum interleukin-1β level, but had higher (p < .05) serum glutathione peroxidase activity than broilers in the Control group. In conclusion, dietary COS supplementation can alleviate heat stress-induced oxidative stress and inflammation response in liver and spleen by decreasing lipid peroxidation, increasing anti-oxidant enzyme activities and IL-10 level. HIGHLIGHTS Dietary COS decreased serum ALT, AST, IL-1β, TNF-α and MDA. Dietary COS increased serum GSH-Px and IL-10, liver SOD, and spleen GSH-Px.

Dietary chitosan oligosaccharides alleviate heat stress–induced intestinal oxidative stress and inflammatory response in yellow-feather broilers

The purpose of this study was to evaluate the effects of chitosan oligosaccharides (COS) on intestinal permeability, morphology, antioxidant status, and inflammatory response in heat-stressed broilers. A total of 108 thirty-five-day-old Chinese yellow-feather broilers (body weight 470.31 ± 13.15 g) were randomly allocated to 3 dietary treatments as follows: CON group, basal diet and raised under normal temperature (24°C); HS group, basal diet and raised under cycle heat stress (34°C from 10:00–18:00 and 24°C for the rest time); 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. Compared with the CON group, heat stress decreased (P < 0.05) the relative weight of duodenum and jejunum; the relative length and villus height (VH) of duodenum, jejunum, and ileum; the ileum VH to crypt depth ratio; duodenum mucosal catalase (CAT) activity; and jejunum mucosal glutathione peroxidase (GSH-Px) and CAT activity, whereas it increased (P < 0.05) serum diamine oxidase (DAO) activity and D-lactate acid (D-LA) content, duodenum and jejunum mucosal malondialdehyde (MDA) and interleukin-1β (IL-1β) content, and ileum mucosal tumor necrosis factor-α content. Compared to the HS group, dietary COS supplementation increased (P < 0.05) the relative length of duodenum, jejunum, and ileum; the VH of jejunum and ileum; and duodenum and jejunum mucosal GSH-Px activity, whereas it decreased (P < 0.05) serum DAO activity and D-LA concentration and duodenum and jejunum mucosal MDA and IL-1β content. These results suggested that dietary COS supplementation had beneficial effects on intestinal morphology by increasing jejunum and ileum VH; permeability by decreasing serum DAO activity and D-LA content; antioxidant capacity by decreasing duodenum and jejunum mucosal MDA content and by increasing duodenum and jejunum GSH-Px activity; and inflammatory response by decreasing duodenum and jejunum mucosal IL-1β content.

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, pH24h, 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, pH24h, 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.

Effects of diet chitosan oligosaccharide on performance and immune response of sows and their offspring

Effects of chitosan oligosaccharide (COS) supplementation to the diets of sow and/or their offspring on performance and immune response were investigated. Multiparous sows (3 to 5 parity; Landrace × Yorkshire) were fed either a control diet (sCON, n = 20) or a diet containing 30 mg kg−1 COS (sCOS, n = 20) from day 86 of gestation until weaning at day 20 of lactation. Piglets from Duroc × Landrace × Yorkshire sires were assigned at 7 days of age within sow treatments and fed either a control diet (pCON) or a diet containing 30 mg kg−1 COS (pCOS) for 28 days. The four piglet treatments (n = 10 per treatment) were: sCON-pCON, sCON-pCOS, sCOS-pCON, and sCOS-pCOS. Sow dietary COS did not significantly change (P > 0.05) number of piglets born, piglet birth and weaning weight, piglet average daily gain (ADG) before and after weaning, piglet average daily feed intake or feed-to-gain ratio after weaning. However, piglet diet COS increased weight at weaning (P = 0.03) and on day 35 of age (P = 0.01), and ADG during lactation (P = 0.03). Sow diet COS increased immunoglobulin (Ig) M content in the colostrum (P = 0.03) and in umbilical cord blood (P = 0.02). Sow diet COS also increased the contents of IgG and interleukin (IL) 10 (P < 0.01), complement 3 (P = 0.03), and tended to increase IgA, IgM and lysozyme (LYZ) concentrations (P = 0.08) in serum of piglets at weaning. Piglet dietary COS did not significantly affect immune-related indexes. In conclusion, sow diets supplying COS improved piglet immune response, and piglet diets supplying COS improved piglet growth rate.