title: Lack of Evidence That Selenium-Yeast Improves Chicken Health and Modulates the Caecal Microbiota in the Context of Colonization byCampylobacter jejuni.
abstract: Faced with ever-increasing demand, the industrial production of food animals is under pressure to increase its production. In order to keep productivity, quality, and safety standards up while reducing the use of antibiotics, farmers are seeking new feed additives. In chicken production, one of these additives is selenium. This element is expected to confer some advantages in terms of animal health and productivity, but its impact on chicken intestinal microbiota as well as on the carriage of foodborne pathogens is unknown. In this study, chickens raised in a level 2 animal facility were fed or not 0.3 ppm of in-feed selenium-yeast until 35 days of age and were inoculated or not with the foodborne pathogenCampylobacter jejuniat the age of 14 days. At the end of the study, body weight, seric IgY, intestinal IgA, seric gluthatione peroxydase activity, the caecal microbiota (analyzed by MiSeq 16S rRNA gene sequencing), andC. jejunicaecal levels were analyzed. The experiment was completely replicated twice, with two independent batches of chickens. This study revealed that, for healthy chickens raised in very good hygienic conditions, selenium-yeast does not influence the bird's body weight and lowers their seric gluthatione peroxidase activity as well as their intestinal IgA concentrations. Furthermore, selenium-yeast did not modify the caecal microbiota or the colonization ofC. jejuni. The results also showed thatC. jejunicolonization does not impact any of the measured chicken health parameters and only slightly impacts the caecal microbiota. This study also clearly illustrated the need for true biological replication (independent animal trials) when assessing the microbiota shifts associated with treatments as the chickens microbiotas clearly clustered according to study replicate.
authors.affiliation: Faculty of Veterinary Medicine, University of Montreal - NSERC Industrial Research Chair in Meat Safety, Saint-Hyacinthe QC, Canada.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Thibodeau
authors.affiliation: Faculty of Veterinary Medicine, University of Montreal - NSERC Industrial Research Chair in Meat Safety, Saint-Hyacinthe QC, Canada.
authors.forename: Ann
authors.initials: A
authors.lastname: Letellier
authors.affiliation: INRS-Institut Armand-Frappier Research Centre, Université du Québec, Laval QC, Canada.
authors.forename: Étienne
authors.initials: É
authors.lastname: Yergeau
authors.affiliation: Faculty of Veterinary Medicine, University of Montreal - NSERC Industrial Research Chair in Meat Safety, Saint-Hyacinthe QC, Canada.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Larrivière-Gauthier
authors.affiliation: Faculty of Veterinary Medicine, University of Montreal - NSERC Industrial Research Chair in Meat Safety, Saint-Hyacinthe QC, Canada.
authors.forename: Philippe
authors.initials: P
authors.lastname: Fravalo
keywords: Campylobacter jejuni; chicken; health; microbiota; selenium