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BACKGROUND: Feed supplements, including essential trace elements are believed to play an important role in augmenting fish immune response. In this context, selenium nanoparticles (SeNPs) in fish diets via a green biosynthesis strategy have attracted considerable interest. In this investigation, selenium nanoparticles (SeNPs, 79.26 nm) synthesized from the green microalga Pediastrum boryanum were incorporated into Nile tilapia diets to explore its beneficial effects on the immune defense and intestinal integrity, in comparison with control basal diets containing inorganic Se source. Nile tilapia (No. 180, 54-57 g) were fed on three formulated diets at concentrations of 0, 0.75, and 1.5 mg/kg of SeNPs for 8 weeks. After the trial completion, tissue bioaccumulation, biochemical indices, antioxidant and pro-inflammatory cytokine-related genes, and intestinal histological examination were analyzed. RESULTS: Our finding revealed that dietary SeNPs significantly decreased (P < 0.05) serum alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and cholesterol, while increasing (P < 0.05) high-density lipoproteins (HDL). The Se concentration in the muscle tissues showed a dose-dependent increase. SeNPs at a dose of 1.5 mg/kg significantly upregulated intestinal interleukin 8 (IL-8) and interleukin 1 beta (IL-1ß) gene transcription compared with the control diet. Glutathione reductase (GSR) and glutathione synthetase (GSS) genes were significantly upregulated in both SeNPs-supplemented groups compared with the control. No apoptotic changes or cell damages were observed as indicated by proliferating cell nuclear antigen (PCNA) and caspase-3 gene expression and evidenced histopathologically. SeNPs supplementation positively affects mucin-producing goblet cells (GCs), particularly at dose of 1.5 mg/kg. CONCLUSION: Therefore, these results suggest that Green synthesized SeNPs supplementation has promising effects on enhancing Nile tilapia immunity and maintaining their intestinal health.
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Cíclidos , Microalgas , Nanopartículas , Selenio , Animales , Selenio/farmacología , Selenio/metabolismo , Microalgas/metabolismo , Suplementos Dietéticos , Dieta/veterinaria , Antioxidantes/metabolismo , Expresión Génica , Alimentación Animal/análisisRESUMEN
A recent study published data on the growth performance, relative weights of the organs of the gastrointestinal tract, liver histology, serum biochemistry, and hematological parameters for turkey poults fed an experimental diet contaminated with aflatoxin B1 (AFB1) and humic acids (HA) extracted from vermicompost. The negative effects of AFB1 (250 ng AFB1/g of feed) were significantly reduced by HA supplementation (0.25% w/w), suggesting that HA might be utilized to ameliorate the negative impact of AFB1 from contaminated diets. The present study shows the results of the remaining variables, as an extension of a previously published work which aimed to evaluate the impact of HA on the intestinal microbiota, gut integrity, ileum morphometry, and cellular immunity of turkey poults fed an AFB1-contaminated diet. For this objective, five equal groups of 1-day-old female Nicholas-700 turkey poults were randomly assigned to the following treatments: negative control (basal diet), positive control (basal diet + 250 ng AFB1/g), HA (basal diet + 0.25% HA), HA + AFB1 (basal diet + 0.25% HA + 250 ng AFB1/g), and Zeolite (basal diet + 0.25% zeolite + 250 ng AFB1/g). In the experiment, seven replicates of ten poults each were used per treatment (n = 70). In general, HA supplementation with or without the presence of AFB1 showed a significant increase (p < 0.05) in the number of beneficial butyric acid producers, ileum villi height, and ileum total area, and a significant reduction in serum levels of fluorescein isothiocyanate-dextran (FITC-d), a marker of intestinal integrity. In contrast, poults fed with AFB1 showed a significant increase in Proteobacteria and lower numbers of beneficial bacteria, clearly suggesting gut dysbacteriosis. Moreover, poults supplemented with AFB1 displayed the lowest morphometric parameters and the highest intestinal permeability. Furthermore, poults in the negative and positive control treatments had the lowest cutaneous basophil hypersensitivity response. These findings suggest that HA supplementation enhanced intestinal integrity (shape and permeability), cellular immune response, and healthier gut microbiota composition, even in the presence of dietary exposure to AFB1. These results complement those of the previously published study, suggesting that HA may be a viable dietary intervention to improve gut health and immunity in turkey poults during aflatoxicosis.
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Microbioma Gastrointestinal , Zeolitas , Animales , Femenino , Aflatoxina B1 , Ácido Butírico , Dieta , Sustancias Húmicas , Inmunidad Celular , PavosRESUMEN
Algae can leverage aquaculture sustainability and improve the nutritional and functional value of fish for human consumption, but may pose challenges to carnivorous fish. This study aimed to evaluate the potential of a commercial blend of macroalgae (Ulva sp. and Gracilaria gracilis) and microalgae (Chlorella vulgaris and Nannochloropsis oceanica) in a plant-based diet up to 6% (dry matter basis) on digestibility, gut integrity, nutrient utilization, growth performance, and muscle nutritional value of European seabass juveniles. Fish (11.3 ± 2.70 g) were fed with isoproteic, isolipidic, and isoenergetic diets: (i) a commercial-type plant-based diet with moderate fishmeal (125 g kg-1 DM basis) and without algae blend (control diet; Algae0), (ii) the control diet with 2% algae blend (Algae2), (iii) the control diet with 4% algae blend (Algae4), and (iv) the control diet with 6% algae blend (Algae6) for 12 weeks. The digestibility of experimental diets was assessed in a parallel study after 20 days. Results showed that most nutrients and energy apparent digestibility coefficients were promoted by algae blend supplementation, with a concomitant increase in lipid and energy retention efficiencies. Growth performance was significantly promoted by the algae blend, the final body weight of fish fed Algae6 being 70% higher than that of fish fed Algae0 after 12 weeks, reflecting up to 20% higher feed intake of algae-fed fish and the enhanced anterior intestinal absorption area (up to 45%). Whole-body and muscle lipid contents were increased with dietary algae supplementation levels by up to 1.79 and 1.74 folds in Algae 6 compared to Algae0, respectively. Even though the proportion of polyunsaturated fatty acids was reduced, the content of EPA and DHA in the muscle of algae-fed fish increased by nearly 43% compared to Algae0. The skin and filet color of juvenile European seabass were significantly affected by the dietary inclusion of the algae blend, but changes were small in the case of muscle, meeting the preference of consumers. Overall results highlight the beneficial effects of the commercial algae blend (Algaessence®) supplementation in plant-based diets for European seabass juveniles, but feeding trials up to commercial-size fish are needed to fully assess its potential.
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The experiment was designed to validate the effect of Artemisia annua and its novel commercial product (Navy Cox) on the control of necrotic enteritis (NE). A total of one hundred forty broiler chicks were randomly distributed into seven equal groups: G1, control negative; G2, infected with Eimeria (day 15) and C. perfringens (day 19); G3, treated with Navy Cox before challenge; G4, treated with Artemisia before challenge; G5, infected and then treated with Navy Cox; G6, infected and then treated with Artemisia; and G7, infected and treated with amoxicillin. Chicken response and immune organ indicants were recorded during the observation period (4 weeks). Whole blood and serum samples were collected for immunological evaluation, and tissue samples were collected for bacterial counts and estimation of mRNA expression of genes encoding apoptosis, tight junctions, and immunity. Chickens in the infected group revealed a significant decrease in RBCS, HB, PCV% total protein, Lysozyme, and nitric oxide activity in addition to leukocytosis, heterophilia, monocytosis, increase in cortisol, interleukins, and malondialdehyde. Treated groups displayed lower lesions, colony-forming units, and no mortality. Concurrently, a complete blood profile, antioxidants, and immune markers showed significant improvements. The mRNA expression levels of CASP, CLDN-1, OCLN, TJPI, MUC2, and cell-mediated immune response genes (p < 0.0001) were significantly alleviated in the treated groups compared with the challenged counterpart. This is the first-ever report on the efficacy valuation of Navy Cox compared to standard antibiotic treatment of clostridial NE. Navy Cox proved remarkable capability to minimize C. perfringens colonization in broiler intestines, modulation of mucus production, gut health integrity, immune organs, and immune response when used as a prophylactic agent in this form or naturally as Artemisia.
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1. The objectives of this study were to i) compare the effects of a commercial product providing encapsulated butyrate (EB) in combination with salinomycin in diets of broilers with impaired intestinal integrity and ii) to identify easy-to-measure biomarkers to evaluate intestinal integrity and health.2. In total, 672 one-day-old male broilers (Ross 308) were randomly assigned to three experimental groups (eight replicates/group): no dietary supplement (control); EB (500 mg/kg, UltraGuard™-DUO, Devenish, Ireland); salinomycin (69 mg/kg feed, Sacox® 120). Impaired gut integrity was induced by a 10 times overdose of a commercially attenuated live vaccine against coccidiosis (Hipracox®, Hipra) on d 17 combined with a grower feed providing rye (50 g/kg diet).3. Improved intestinal integrity and functionality were reflected by reduced fluorescein isothiocyanate-dextran (FITC-D) plasma levels, reduced bacterial translocation to the liver (on d 21) and increased plasma colouration level on d 21 after dietary supplementation of salinomycin, compared to a non-supplemented control diet. Both EB and salinomycin reduced plasma levels of D-lactate (P < 0.05).4. An anti-inflammatory effect of salinomycin was indicated as the transient increase in circulating monocytes observed in the EB and control group from 20 to 28 d of age was slightly but not significantly reduced, in the salinomycin-fed group. Interestingly, greater expression of tumour necrosis factor α (TNF-α) and mucin 2 (MUC2) genes (P = 0.039 and P = 0.067, respectively) were detected in the group receiving salinomycin.5. These effects may have collectively contributed to the significantly improved performance of broilers supplemented with salinomycin. The results indicated that EB at 500 mg/kg in feed, in contrast to salinomycin, neither supported gut health nor modulated intestinal integrity in broilers.
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Alimentación Animal , Pollos , Alimentación Animal/análisis , Animales , Butiratos/efectos adversos , Pollos/microbiología , Suplementos Dietéticos , Inflamación/inducido químicamente , Inflamación/veterinaria , Masculino , PiranosRESUMEN
Background and Aims: Vitamin D (VD) plays an important role not only in mineral balance and skeletal maintenance but also in immune modulation. VD status was found correlated with the pathophysiology and severity of inflammatory bowel diseases and other autoimmune disorders. Epithelial barrier function is primarily regulated by the tight-junction (TJ) proteins. In this study, we try to establish an animal model by raising mice fed VD-deficient diet and to investigate the effects of VD-deficient diet on gut integrity and zonulin expression. Methods: Male C57BL/6 mice were administered either VD-deficient [VDD group, 25(OH)2D3 0 IU/per mouse] or VD-sufficient [VDS group, 25(OH)2D3 37.8 IU/per mouse] special diets for 7 weeks. Body weight and diet intake were recorded weekly. Serum VD levels were detected. After sacrifice, jejunum and colon specimens were collected. The villus length and crypt depth of the jejunum as well as mucosa thickness of the colon were measured. Various serum pro-inflammatory cytokines and intestinal TJ proteins were assessed. The serum level of zonulin and the mRNA expression of jejunum zonulin were also investigated. Results: We found that mice fed a VDD diet had a lower serum level of VD after 7 weeks (p < 0.001). VDD mice gained significant less weight (p = 0.022) and took a similar amount of diet (p = 0.398) when compared to mice raised on a VDS diet. Significantly decreased colon mucosa thickness was found in VDD mice compared with the VDS group (p = 0.022). A marked increase in serum pro-inflammatory cytokine levels was demonstrated in VDD mice. All relative levels of claudin (CLD)-1 (p = 0.007), CLD-3 (p < 0.001), CLD-7 (p < 0.001), and zonulin-1 (ZO-1, p = 0.038) protein expressions were significantly decreased in the VDD group when compared to the VDS group. A significant upregulation of mRNA expression of jejunum zonulin (p = 0.043) and elevated serum zonulin (p = 0.001) were found in the VDD group. Conclusions: We successfully demonstrated that VDD could lead to impaired barrier properties. We assume that sufficient VD could maintain intestinal epithelial integrity and prevent mucosal barrier dysfunction. VD supplementation may serve as part of a therapeutic strategy for human autoimmune and infectious diseases with intestinal barrier dysfunction (leaky gut) in the future. To our knowledge, this is the first study to demonstrate that VDD could lead to a significant upregulation in mRNA expression of the jejunum zonulin level and also a marked elevation of serum zonulin in a mouse model.
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Broiler chickens reared under heat stress (HS) conditions have decreased growth performance and show metabolic and immunologic alterations. This study aimed to evaluate the effect of supplementation with a standardized blend of plant-derived isoquinoline alkaloids (IQ) on the growth performance, protein catabolism, intestinal barrier function, and inflammatory status of HS-treated chickens. Three hundred sixty 0-day-old Ross 308 male broiler chickens were randomly distributed into 2 treatment groups: control diet (no additives) or diet supplemented with 100 ppm IQ. At day 14, the chicks in each diet group were further divided into 2 groups, each of which was reared under thermoneutral (TN) (22.4°C) or constant HS (33.0°C) conditions until day 42. Each group consisted of 6 replicates with 15 birds per replicate, and chickens were provided ad libitum access to water and feed. During days 15-21, the body weight gain (BWG) and feed intake (FI) were significantly lower in the HS treatment group than in the TN group, and feed conversion ratio was higher (P < 0.05); these factors were not alleviated by IQ supplementation. During days 22-42, the final BW, BWG, and FI of the HS birds were better among those administered IQ than those that were not (P < 0.05). HS treatment increased plasma lipid peroxide, corticosterone, and uric acid concentrations as well as serum fluorescein isothiocyanate-dextran, a marker of intestinal barrier function, and decreased plasma total protein content (P < 0.05). These changes were not observed in the IQ group, suggesting that IQ supplementation improved oxidative damage, protein catabolism, and intestinal barrier function of chickens under HS. Isoquinoline alkaloid supplementation inhibited the expression of intestinal inflammatory factors, IL-6, tumor necrosis factor-like factor 1A, and inducible nitric oxide synthase under HS treatment (P < 0.05). These results suggest that IQ supplementation can improve the growth performance of broiler chickens under HS conditions, which may be associated with amelioration of oxidative damage, protein catabolism, intestinal barrier function, and inflammation.
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Alcaloides/farmacología , Pollos/fisiología , Respuesta al Choque Térmico/fisiología , Intestinos/efectos de los fármacos , Isoquinolinas/administración & dosificación , Alcaloides/administración & dosificación , Alimentación Animal/análisis , Animales , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Suplementos Dietéticos , Calor , Intestinos/fisiología , Isoquinolinas/química , MasculinoRESUMEN
Diminished integrity of the intestinal epithelial barrier with advanced age is believed to contribute to aging-associated dysfunction and pathologies in animals. In mammals, diminished gut integrity contributes to inflammaging, the increase in inflammatory processes observed in old age. Recent work suggests that expression of intestinal alkaline phosphatase (IAP) plays a key role in maintaining gut integrity. IAP expression decreases with increasing age in mice and humans. Absence of IAP leads to liver inflammation and shortened life-spans in mice lacking the IAP gene. In normal mice, exogenous supplemental IAP reverses age-induced barrier dysfunction, improves aging-associated metabolic dysfunction, prevents microbiome dysbiosis (imbalance), and extends life-span. Consistent with IAP playing a conserved role in maintaining gut integrity, increased dietary IAP increases aging-diminished physical performance in flies. IAP helps maintain gut integrity in part by supporting the expression of tight junction proteins that maintain the intestinal epithelial barrier and by inactivating bacterial pro-inflammatory factors such as lipopolysaccharides (LPS) by dephosphorylation. Recombinant IAP is in late clinical trials for sepsis-associated acute kidney injury, suggesting it may soon become available as a therapeutic. Taken together, these reports support the idea that directly increasing IAP levels by supplemental recombinant IAP or by indirectly increasing IAP levels using dietary means to induce endogenous IAP may slow the development of aging-associated pathologies.
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Fosfatasa Alcalina , Lipopolisacáridos , Envejecimiento , Animales , Suplementos Dietéticos , Ratones , MicrovellosidadesRESUMEN
Peptides from fish may beneficially affect several metabolic outcomes, including gut health and inflammation. The effect of fish peptides in subjects with irritable bowel syndrome (IBS) has not previously been investigated, hence this study aimed to evaluate the effect of a cod protein hydrolysate (CPH) supplement on symptom severity, gut integrity markers and fecal fermentation in IBS-patients. A double-blind, randomized parallel-intervention with six weeks of supplementation with 2.5 g CPH (n = 13) or placebo (n = 15) was conducted. The outcomes were evaluated at baseline and the end of the study. The primary outcomes were symptom severity evaluated by the IBS severity scoring system (IBS-SSS) and quality of life. The secondary outcomes included gut integrity markers and pro-inflammatory cytokines in serum, fecal fermentation measured by concentration of short-chain fatty acids (SCFAs) and fecal calprotectin. The groups were comparable at baseline. The total IBS-SSS-scores were reduced in both the CPH-group (298 ± 69 to 236 ± 106, p = 0.081) and the placebo-group (295 ± 107 to 202 ± 103, p = 0.005), but the end of study-scores did not differ (p = 0.395). The concentrations of serum markers and SCFAs did not change for any of the groups. The baseline measures for the whole group showed that the total SCFA concentrations were inversely correlated with the total IBS-SSS-score (r = -0.527, p = 0.004). Our study showed that a low dose of CPH taken daily by IBS-patients for six weeks did not affect symptom severity, gut integrity markers or fecal fermentation when compared to the placebo group.
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Suplementos Dietéticos , Proteínas de Peces/química , Proteínas de Peces/uso terapéutico , Gadiformes , Síndrome del Colon Irritable/tratamiento farmacológico , Animales , Registros de Dieta , Método Doble Ciego , Ácidos Grasos Volátiles/química , Heces/química , Femenino , Fermentación , Humanos , Hidrólisis , MasculinoRESUMEN
This study evaluated the effect of reduced dietary energy (ME) and crude protein (CP) levels along with inclusion of a phytogenic feed additive (PFA) on gut microbiota composition and gene expression of Toll-like receptor(s) (TLR), tight junction proteins, and inflammatory cytokines expressed in secondary lymphoid organs. Depending on dietary ME and CP level down regulation and the inclusion or not of PFA at 125 mg/kg diet, 450 one-day-old male broilers were allocated in the following 6 treatments for 42 D according to a 3 × 2 factorial design: A: diet formulated optimally to meet broiler nutrient requirements; APh: A+PFA; B: suboptimal in ME and CP levels by 3%; BPh: B+PFA; C: suboptimal in ME and CP levels by 6%; CPh: C+PFA. Diet type and PFA supplementation were shown to affect mostly the mucosa-associated microbiota compared to the luminal ones. Ileal mucosa-associated total bacteria (PD= 0.005), Lactobacillus spp. (PD= 0.003), and Clostridium cluster XIVa (PD= 0.009) were affected by diet type with broilers fed diet B having lower levels compared to broilers fed diets A or C. Moreover, diet type affected cecal mucosa-associated Lactobacillus spp. (PD= 0.002) with broilers fed diet C having lower levels compared to broilers fed diets A or B. Supplementation with PFA resulted in higher levels of cecal mucosa-associated Bacteroides (PP= 0.031), Clostridium cluster IV (PP= 0.007), and Clostridium cluster XIVa (PP= 0.039). Diet type affected TLR2 (PD= 0.046) and claudin 5 (PD= 0.027) in cecal epithelium. Lower TLR2 (PP= 0.021) and higher zonula occludens 2 (PP= 0.031) relative gene expressions were seen in ileal epithelium following PFA supplementation. Moreover, in cecal epithelium, PFA supplementation resulted in lower TLR2 (PP < 0.001) and higher zonula occludens 2 (PP= 0.009), claudin 5 (PP= 0.005) and occludin (PP= 0.039) relative gene expressions. There were no significant diet type and PFA effects on cytokines in secondary lymphoid organs, except for a dietary effect on transforming growth factor beta 4 (PD= 0.023) in cecal tonsils. In conclusion, PFA inclusion beneficially modulated elements of gut microbiota, Toll-like signaling molecules and gut tight junction genes.
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Proteínas Aviares/genética , Pollos/genética , Pollos/microbiología , Suplementos Dietéticos/análisis , Microbioma Gastrointestinal , Expresión Génica , Alimentación Animal/análisis , Animales , Proteínas Aviares/metabolismo , Ciego/efectos de los fármacos , Ciego/metabolismo , Citocinas/genética , Citocinas/metabolismo , Dieta/veterinaria , Microbioma Gastrointestinal/efectos de los fármacos , Expresión Génica/genética , Íleon/efectos de los fármacos , Íleon/metabolismo , Masculino , Distribución Aleatoria , Bazo/efectos de los fármacos , Bazo/metabolismo , Proteínas de Uniones Estrechas/genética , Proteínas de Uniones Estrechas/metabolismo , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismoRESUMEN
BACKGROUND: The current study was designed to assess the effect of supplementation with a 14-strain probiotic mixture on episodic and chronic migraine characteristics. METHODS: Forty episodic and 39 chronic migraine patients who completed this randomized double-blind controlled trial received two capsules of multispecies probiotic or placebo. The migraine severity was assessed by visual analog scale (VAS). The number of abortive drugs consumed, migraine days, frequency and duration of attacks were recorded on paper-based headache diaries. Serum tumor necrosis factor alpha (TNF-α) and C- reactive protein (CRP) levels were measured at baseline and the end of the intervention. RESULTS: After a 10-week intervention, among episodic migraineurs the mean frequency of migraine attacks significantly reduced in the probiotic group compare to the placebo group (mean change: -2.64 vs. 0.06; respectively, p < 0.001). A significant reduction was also evident in the migraine severity (mean decrease: -2.14 in the probiotic group and 0.11 in the placebo group; p < 0.001). Episodic migraineurs who received the probiotic also showed significant reduction in abortive drug usage per week (mean change: -0.72; p < 0.001) compare to baseline, while there was no significant changes within the placebo group. In chronic migraine patients, after an 8-week intervention, the mean frequency of migraine attacks significantly reduced in the probiotic compared to the placebo group (mean change: -9.67 vs. -0.22; p ≤ 0.001). In contrast to the placebo, probiotic supplementation significantly decreased the severity (mean changes: -2.69; p ≤ 0.001), duration (mean changes: -0.59; p ≤ 0.034) of attacks and the number of abortive drugs taken per day (mean changes: -1.02; p < 0.001), in chronic migraine patients. We failed to detect any significant differences in the serum levels of inflammatory markers at the end of the study either in chronic or in episodic migraineurs. DISCUSSION: The results of this study showed that the 14-strain probiotic mixture could be an effective and beneficial supplement to improve migraine headache in both chronic and episodic migraineurs. Further research is required to confirm our observations.
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Suplementos Dietéticos , Trastornos Migrañosos/dietoterapia , Probióticos/uso terapéutico , Adulto , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
Feeding chickens diets high in n-3 fatty acids (FA) increases their incorporation into tissue lipids, but leads to oxidative stress in cells. This study investigated the effect of the dietary polyunsaturated FA ratio (PUFA n-6: n-3) and vitamin E (vE) level on DNA damage and morphological changes in the gut epithelium of chickens. One-day-old female broiler chicks (n = 176) were divided into 4 groups fed for 43 d diets with a high (HR) or low (LR) PUFA n-6: n-3 ratio and supplemented with 50 or 300 mg vE kg-1. Performance was calculated for periods of d 1 to 9, d 9 to 16, d 9 to 35, and d 9 to 42, while organs were sampled at d 9, d 17, d 36, and d 43. At d 17 and d 43, DNA damage of epithelial cells in the duodenum and jejunum was measured and duodenal and jejunal morphology was analyzed. HR diets improved FCR for the periods of d 1 to 9, d 9 to 16 and d 9 to 42, whereas the increased vE level improved FCR for the period of d 9 to 16. In the jejunum DNA damage was greater in chickens fed LR than HR diets at d 17 (P < 0.001) and the increased vE level promoted DNA damage in both intestinal segments (P < 0.02) in younger birds. The morphology of the duodenum was marginally affected by the diets, whereas LR diets in the jejunum reduced villus surface area at d 17 (P = 0.022), and mucosa thickness (P = 0.029) and villus height (P = 0.035) at d 43. The results indicated that feeding birds LR diets and vE levels significantly exceeding the recommendation induced DNA damage in epithelial cells, but this effect varied depending on the intestinal segment and the age of birds.