This page has only limited features, please log in for full access.
Antibiotics have played a critical role in sustaining and improving livestock production in the past decades, but the emergence of antimicrobial resistance has led several countries to ban or limit their use. Since then, in-feed alternatives have gained a lot of attention but the development of efficacious alternatives implies a better understanding of the mode of action of antibiotic growth promoters (AGPs) when administered at subtherapeutic concentrations. In the present study, 120 broiler chickens per group (8 pens/group) were fed for 35 days with either basal feed (control group) or feed supplemented with avilamycin (AGP group; 10 g/1000 kg of feed). At the end of the trial, the ileum from the small intestine of five birds per group was sampled, and RNA were isolated for profiling their transcriptome via RNA sequencing (RNA-Seq). As expected, the growth of chickens in the AGP group was significantly higher than in the control group. Overall, 66 differentially expressed genes (DEGs; FDR ≤ 0.05 and fold change ≥ 2 or ≤ -2) were found in the ileum of chicken fed avilamycin in comparison to the control group. The functional analysis showed reduced activity of genes related to signaling by interleukins, with IL-22, SOCS3 and certain antimicrobial peptides found multiple times in these pathways in the AGP group at day 35. In addition, higher activity was predicted in a module of genes related to lipid metabolism and transport in the avilamycin group. The use of RNA-Seq allowed a snapshot of the whole transcriptome at day 35, and aimed at delivering additional data on the host-centric hypothesis regarding the mode of action of AGPs (i.e. immunomodulation, reduction of the immunological stress).
Silvia Fibi-Smetana; Candida Vaz; Jeremy Le Coz; Suzana Ilic; Roger Berrios; Gerd Schatzmayr; Vivek Tanavde; Bertrand Grenier. Research Note: Snapshot of the transcriptome via RNA sequencing in the ileum of broiler chickens fed subtherapeutic concentrations of avilamycin. Poultry Science 2020, 100, 998 -1003.
AMA StyleSilvia Fibi-Smetana, Candida Vaz, Jeremy Le Coz, Suzana Ilic, Roger Berrios, Gerd Schatzmayr, Vivek Tanavde, Bertrand Grenier. Research Note: Snapshot of the transcriptome via RNA sequencing in the ileum of broiler chickens fed subtherapeutic concentrations of avilamycin. Poultry Science. 2020; 100 (2):998-1003.
Chicago/Turabian StyleSilvia Fibi-Smetana; Candida Vaz; Jeremy Le Coz; Suzana Ilic; Roger Berrios; Gerd Schatzmayr; Vivek Tanavde; Bertrand Grenier. 2020. "Research Note: Snapshot of the transcriptome via RNA sequencing in the ileum of broiler chickens fed subtherapeutic concentrations of avilamycin." Poultry Science 100, no. 2: 998-1003.
Lipopolysaccharides (LPS), also termed endotoxins, are the major component of the outer membrane of Gram-negative bacteria. In general, endotoxins in the intestine are considered harmless in healthy animals. However, different stressors, such as heat stress, can lead to a compromised gut barrier, resulting in endotoxin translocation. Chickens are considered to be less sensitive to the effects of LPS compared with other species, for example, humans, pigs, or calves, probably because of the lack of the functional-specific TRAM-TRIF signalling pathway (MyD88-independent). Therefore, six LPS preparations (three different strains with two different preparation methods each) were compared in murine macrophages and characterized according to their MyD88-dependent pathway activation. All tested LPS preparations induced a strong inflammatory response after 4 and 24 h on a murine macrophage cell line. However, there was a similar strong response in the gene expression profile as well as production of nitrite oxide and TNF-alpha from LPS of different strains and preparation methods. On the basis of the results of the in vitro study, one LPS preparation was chosen for the subsequent in vivo study with broilers to assess the effect of an oral LPS bolus (E. coli O55:B5 phenol extracted; 2 mg/kg b.w.) during heat stress conditions (10 h, 36 °C). The most pronounced effects were seen in broilers receiving the oral LPS bolus during heat stress conditions. The endotoxin activity in the intestine as well as the serum concentration of the 3-OH C14 (part of LPS) were increased. In addition, an increased expression of genes related to inflammation and stress response (e.g., IL-6, IL-1beta, HSP70) was observed, whereas the expression of genes associated with gut health (e.g., MUC2, FABP2) was decreased. To conclude, an increase of intestinal LPS combined with heat stress can pose a risk to animal health.
Nicole Reisinger; Caroline Emsenhuber; Barbara Doupovec; Elisabeth Mayer; Gerd Schatzmayr; Veronika Nagl; Bertrand Grenier. Endotoxin Translocation and Gut Inflammation Are Increased in Broiler Chickens Receiving an Oral Lipopolysaccharide (LPS) Bolus during Heat Stress. Toxins 2020, 12, 622 .
AMA StyleNicole Reisinger, Caroline Emsenhuber, Barbara Doupovec, Elisabeth Mayer, Gerd Schatzmayr, Veronika Nagl, Bertrand Grenier. Endotoxin Translocation and Gut Inflammation Are Increased in Broiler Chickens Receiving an Oral Lipopolysaccharide (LPS) Bolus during Heat Stress. Toxins. 2020; 12 (10):622.
Chicago/Turabian StyleNicole Reisinger; Caroline Emsenhuber; Barbara Doupovec; Elisabeth Mayer; Gerd Schatzmayr; Veronika Nagl; Bertrand Grenier. 2020. "Endotoxin Translocation and Gut Inflammation Are Increased in Broiler Chickens Receiving an Oral Lipopolysaccharide (LPS) Bolus during Heat Stress." Toxins 12, no. 10: 622.
Zearalenone (ZEN)-degrading enzymes are a promising strategy to counteract the negative effects of this mycotoxin in livestock. The reaction products of such enzymes need to be thoroughly characterized before technological application as a feed additive can be envisaged. Here, we evaluated the estrogenic activity of the metabolites hydrolyzed zearalenone (HZEN) and decarboxylated hydrolyzed zearalenone (DHZEN) formed by hydrolysis of ZEN by the zearalenone-lactonase Zhd101p. ZEN, HZEN, and DHZEN were tested in two in vitro models, the MCF-7 cell proliferation assay (0.01-500 nM) and an estrogen-sensitive yeast bioassay (1-10,000 nM). In addition, we compared the impact of dietary ZEN (4.58 mg/kg) and equimolar dietary concentrations of HZEN and DHZEN on reproductive tract morphology as well as uterine mRNA and microRNA expression in female piglets (n = 6, four weeks exposure). While ZEN increased cell proliferation and reporter gene transcription, neither HZEN nor DHZEN elicited an estrogenic response, suggesting that these metabolites are at least 50-10,000 times less estrogenic than ZEN in vitro. In piglets, HZEN and DHZEN did not increase vulva size or uterus weight. Moreover, RNA transcripts altered upon ZEN treatment (EBAG9, miR-135a-5p, miR-187-3p and miR-204-5p) were unaffected by HZEN and DHZEN. Our study shows that both metabolites exhibit markedly reduced estrogenicity in vitro and in vivo, and thus provides an important basis for further evaluation of ZEN-degrading enzymes.
Sebastian Fruhauf; Barbara Novak; Veronika Nagl; Matthias Hackl; Doris Hartinger; Valentina Rainer; Silvia Labudová; Gerhard Adam; Markus Aleschko; Wulf-Dieter Moll; Michaela Thamhesl; Bertrand Grenier. Biotransformation of the Mycotoxin Zearalenone to its Metabolites Hydrolyzed Zearalenone (HZEN) and Decarboxylated Hydrolyzed Zearalenone (DHZEN) Diminishes its Estrogenicity In Vitro and In Vivo. Toxins 2019, 11, 481 .
AMA StyleSebastian Fruhauf, Barbara Novak, Veronika Nagl, Matthias Hackl, Doris Hartinger, Valentina Rainer, Silvia Labudová, Gerhard Adam, Markus Aleschko, Wulf-Dieter Moll, Michaela Thamhesl, Bertrand Grenier. Biotransformation of the Mycotoxin Zearalenone to its Metabolites Hydrolyzed Zearalenone (HZEN) and Decarboxylated Hydrolyzed Zearalenone (DHZEN) Diminishes its Estrogenicity In Vitro and In Vivo. Toxins. 2019; 11 (8):481.
Chicago/Turabian StyleSebastian Fruhauf; Barbara Novak; Veronika Nagl; Matthias Hackl; Doris Hartinger; Valentina Rainer; Silvia Labudová; Gerhard Adam; Markus Aleschko; Wulf-Dieter Moll; Michaela Thamhesl; Bertrand Grenier. 2019. "Biotransformation of the Mycotoxin Zearalenone to its Metabolites Hydrolyzed Zearalenone (HZEN) and Decarboxylated Hydrolyzed Zearalenone (DHZEN) Diminishes its Estrogenicity In Vitro and In Vivo." Toxins 11, no. 8: 481.
The mycotoxin zearalenone (ZEN) poses a risk to animal health because of its estrogenic effects. Diagnosis of ZEN-induced disorders remains challenging due to the lack of appropriate biomarkers. In this regard, circulating microRNAs (small non-coding RNAs) have remarkable potential, as they can serve as indicators for pathological processes in tissue. Thus, we combined untargeted and targeted transcriptomics approaches to investigate the effects of ZEN on the microRNA expression in porcine uterus, jejunum and serum, respectively. To this end, twenty-four piglets received uncontaminated feed (Control) or feed containing 0.17 mg/kg ZEN (ZEN low), 1.46 mg/kg ZEN (ZEN medium) and 4.58 mg/kg ZEN (ZEN high). After 28 days, the microRNA expression in the jejunum remained unaffected, while significant changes in the uterine microRNA profile were observed. Importantly, 14 microRNAs were commonly and dose-dependently affected in both the ZEN medium and ZEN high group, including microRNAs from the miR-503 cluster (i.e. ssc-miR-424-5p, ssc-miR-450a, ssc-miR-450b-5p, ssc-miR-450c-5p, ssc-miR-503 and ssc-miR-542-3p). Predicted target genes for those microRNAs are associated with regulation of gene expression and signal transduction (e.g. cell cycle). Although the effects in serum were less pronounced, receiver operating characteristic analysis revealed that several microRNA ratios were able to discriminate properly between non-exposed and ZEN-exposed pigs (e.g. ssc-miR-135a-5p/ssc-miR-432-5p, ssc-miR-542-3p/ssc-miR-493-3p). This work sheds new light on the molecular mechanisms of ZEN, and fosters biomarker discovery.
Bertrand Grenier; Matthias Hackl; Susanna Skalicky; Michaela Thamhesl; Wulf-Dieter Moll; Roger Berrios; Gerd Schatzmayr; Veronika Nagl. MicroRNAs in porcine uterus and serum are affected by zearalenone and represent a new target for mycotoxin biomarker discovery. Scientific Reports 2019, 9, 1 -14.
AMA StyleBertrand Grenier, Matthias Hackl, Susanna Skalicky, Michaela Thamhesl, Wulf-Dieter Moll, Roger Berrios, Gerd Schatzmayr, Veronika Nagl. MicroRNAs in porcine uterus and serum are affected by zearalenone and represent a new target for mycotoxin biomarker discovery. Scientific Reports. 2019; 9 (1):1-14.
Chicago/Turabian StyleBertrand Grenier; Matthias Hackl; Susanna Skalicky; Michaela Thamhesl; Wulf-Dieter Moll; Roger Berrios; Gerd Schatzmayr; Veronika Nagl. 2019. "MicroRNAs in porcine uterus and serum are affected by zearalenone and represent a new target for mycotoxin biomarker discovery." Scientific Reports 9, no. 1: 1-14.
Fumonisins (FB) are among the most frequently detected mycotoxins in feedstuffs and finished feed, and recent data suggest that the functions of the gastrointestinal tract (GIT) in poultry species might be compromised at doses ranging from 10 to 20 mg/kg, close to field incidences and below the US and EU guidelines. Strategies are therefore necessary to reduce the exposure of poultry to FB. In the present study, we assessed the efficacy of fumonisin esterase FumD (EC 3.1.1.87, commercial name FUMzyme®) to cleave the tricarballylic acid side chains of FB, leading to the formation of non-toxic hydrolyzed fumonisins in the GIT of broiler chickens. Broiler chickens were fed for 14 d (7 to 21 d of age) 3 different diets (6 birds/cage, 6 cages/diet), i) control feed (negative control group), ii) feed contaminated with 10 mg FB/kg (FB group), and iii) feed contaminated with 10 mg FB/kg and supplemented with 100 units of FUMzyme®/kg (FB+FUMzyme® group). To determine the degree of reduction of FB in the GIT, 2 characteristics were analyzed. First, the sphinganine-to-sphingosine ratio in the serum and liver was determined as a biomarker of effect for exposure to FB. Second, the concentration of fumonisin B1 and its hydrolyzed forms was evaluated in the gizzard, the proximal and distal parts of the small intestine, and the excreta. Significantly reduced sphinganine-to-sphingosine ratios in the serum and liver of the FB+FUMzyme® group (serum: 0.15 ± 0.01; liver: 0.17 ± 0.01) compared to the FB group (serum: 0.20 ± 0.01; liver: 0.29 ± 0.03) proved that supplementation of broiler feed with FUMzyme® was effective in partially counteracting the toxic effect of dietary FB. Likewise, FB concentrations in digesta and excreta were significantly reduced in the FB+FUMzyme® group compared to the FB group (P < 0.05; up to 75%). FUMzyme® furthermore partially counteracted FB-induced up-regulation of cytokine gene expression (IL-8 and IL-10) in the jejunum. The FB group showed significantly higher gene expression of IL-8 and IL-10 compared to the negative control group (IL-8: fold change = 2.9 ± 1.1, P < 0.05; IL-10: fold change = 3.6 ± 1.4, P < 0.05), whereas IL-8 and IL-10 mRNA levels were not significantly different in the FB+FUMzyme®® group compared to the other 2 groups. In conclusion, FUMzyme® is suitable to detoxify FB in chickens and maintain gut functions.
B Grenier; Heidi Schwartz-Zimmermann; C Gruber-Dorninger; I Dohnal; M Aleschko; G Schatzmayr; Wulf-Dieter Moll; T J Applegate. Enzymatic hydrolysis of fumonisins in the gastrointestinal tract of broiler chickens. Poultry Science 2017, 96, 4342 -4351.
AMA StyleB Grenier, Heidi Schwartz-Zimmermann, C Gruber-Dorninger, I Dohnal, M Aleschko, G Schatzmayr, Wulf-Dieter Moll, T J Applegate. Enzymatic hydrolysis of fumonisins in the gastrointestinal tract of broiler chickens. Poultry Science. 2017; 96 (12):4342-4351.
Chicago/Turabian StyleB Grenier; Heidi Schwartz-Zimmermann; C Gruber-Dorninger; I Dohnal; M Aleschko; G Schatzmayr; Wulf-Dieter Moll; T J Applegate. 2017. "Enzymatic hydrolysis of fumonisins in the gastrointestinal tract of broiler chickens." Poultry Science 96, no. 12: 4342-4351.
Deoxynivalenol (DON) and fumonisins (FB) are the most frequently encountered mycotoxins produced by Fusarium species in livestock diets. The effect of subclinical doses of mycotoxins in chickens is largely unknown, and in particular the susceptibility of birds to pathogenic challenge when fed these fungal metabolites. Therefore, the present study reports the effects of DON and FB on chickens challenged with Eimeria spp, responsible for coccidiosis. Broilers were fed diets from hatch to day 20, containing no mycotoxins, 1.5 mg DON/kg, 20 mg FB/kg, or both toxins (12 pens/diet; 7 birds/pen). At day 14, six pens of birds per diet (half of the birds) were challenged with a 25×-recommended dose of coccidial vaccine, and all birds (challenged and unchallenged) were sampled 6 days later. As expected, performance of birds was strongly affected by the coccidial challenge. Ingestion of mycotoxins did not further affect the growth but repartitioned the rate of reduction (between the fraction due to the change in maintenance and feed efficiency), and reduced apparent nitrogen digestibility. Intestinal lesions and number of oocysts in the jejunal mucosa and feces of challenged birds were more frequent and intense in the birds fed mycotoxins than in birds fed control feed. The upregulation of cytokines (interleukin (IL) IL-1β, IL-6, IL-8 and IL-10) following coccidial infection was higher in the jejunum of birds fed mycotoxins. Further, the higher intestinal immune response was associated with a higher percentage of T lymphocytes CD4+CD25+, also called Tregs, observed in the cecal tonsils of challenged birds fed mycotoxins. Interestingly, the increase in FB biomarker of exposure (sphinganine/sphingosine ratio in serum and liver) suggested a higher absorption and bioavailability of FB in challenged birds. The interaction of DON and FB was very dependent on the endpoint assessed, with three endpoints reporting antagonism, nine additivity, and two synergism. In conclusion, subclinical doses of DON and FB showed little effects in unchallenged chickens, but seem to result in metabolic and immunologic disturbances that amplify the severity of coccidiosis.
Bertrand Grenier; Ilse Dohnal; Revathi Shanmugasundaram; Susan D. Eicher; Ramesh K. Selvaraj; Gerd Schatzmayr; Todd J. Applegate. Susceptibility of Broiler Chickens to Coccidiosis When Fed Subclinical Doses of Deoxynivalenol and Fumonisins—Special Emphasis on the Immunological Response and the Mycotoxin Interaction. Toxins 2016, 8, 231 .
AMA StyleBertrand Grenier, Ilse Dohnal, Revathi Shanmugasundaram, Susan D. Eicher, Ramesh K. Selvaraj, Gerd Schatzmayr, Todd J. Applegate. Susceptibility of Broiler Chickens to Coccidiosis When Fed Subclinical Doses of Deoxynivalenol and Fumonisins—Special Emphasis on the Immunological Response and the Mycotoxin Interaction. Toxins. 2016; 8 (8):231.
Chicago/Turabian StyleBertrand Grenier; Ilse Dohnal; Revathi Shanmugasundaram; Susan D. Eicher; Ramesh K. Selvaraj; Gerd Schatzmayr; Todd J. Applegate. 2016. "Susceptibility of Broiler Chickens to Coccidiosis When Fed Subclinical Doses of Deoxynivalenol and Fumonisins—Special Emphasis on the Immunological Response and the Mycotoxin Interaction." Toxins 8, no. 8: 231.
In chickens, the effect of mycotoxins, especially fumonisins (FB), in the gastrointestinal tract (GIT) is not well documented. Thus, this study in broiler chicks determined the effects of consuming diets prepared with Fusarium verticillioides culture material containing FB on intestinal gene expression and on the sphinganine (Sa)/sphingosine (So) ratio (Sa/So; a biomarker of FB effect due to disruption of sphingolipid metabolism). Male broilers were assigned to 6 diets (6 cages/diet; 6 birds/cage) from hatch to 20 days containing 0.4, 5.6, 11.3, 17.5, 47.8, or 104.8 mg FB/kg diet. Exposure to FB altered the Sa/So ratio in all tissues analyzed, albeit to varying extents. Linear dose-responses were observed in the kidney, jejunum and cecum. The liver and the ileum were very sensitive and data fit a cubic and quadratic polynomial model, respectively. Gene expression in the small intestine revealed low but significant upregulations of cytokines involved in the pro-inflammatory, Th1/Th17 and Treg responses, especially at 10 days of age. Interestingly, the cecal tonsils exhibited a biphasic response. Unlike the sphingolipid analysis, the effects seen on gene expression were not dose dependent, even showing more effects when birds were exposed to 11.3 mg FB/kg. In conclusion, this is the first report on the disruption of the sphingolipid metabolism by FB in the GIT of poultry. Further studies are needed to reach conclusions on the biological meaning of the immunomodulation observed in the GIT, but the susceptibility of chickens to intestinal pathogens when exposed to FB, at doses lower than those that would cause overt clinical symptoms, should be addressed.
Bertrand Grenier; Heidi E. Schwartz-Zimmermann; Sylvia Caha; Wulf Dieter Moll; Gerd Schatzmayr; Todd J. Applegate. Dose-Dependent Effects on Sphingoid Bases and Cytokines in Chickens Fed Diets Prepared with Fusarium Verticillioides Culture Material Containing Fumonisins. Toxins 2015, 7, 1253 -1272.
AMA StyleBertrand Grenier, Heidi E. Schwartz-Zimmermann, Sylvia Caha, Wulf Dieter Moll, Gerd Schatzmayr, Todd J. Applegate. Dose-Dependent Effects on Sphingoid Bases and Cytokines in Chickens Fed Diets Prepared with Fusarium Verticillioides Culture Material Containing Fumonisins. Toxins. 2015; 7 (4):1253-1272.
Chicago/Turabian StyleBertrand Grenier; Heidi E. Schwartz-Zimmermann; Sylvia Caha; Wulf Dieter Moll; Gerd Schatzmayr; Todd J. Applegate. 2015. "Dose-Dependent Effects on Sphingoid Bases and Cytokines in Chickens Fed Diets Prepared with Fusarium Verticillioides Culture Material Containing Fumonisins." Toxins 7, no. 4: 1253-1272.