Comparative analysis of the caecal tonsil transcriptome in two chicken lines experimentally infected with Salmonella Enteritidis

PLoS One. 2022 Aug 17;17(8):e0270012. doi: 10.1371/journal.pone.0270012. eCollection 2022.

Abstract

Managing Salmonella enterica Enteritidis (SE) carriage in chicken is necessary to ensure human food safety and enhance the economic, social and environmental sustainability of chicken breeding. Salmonella can contaminate poultry products, causing human foodborne disease and economic losses for farmers. Both genetic selection for a decreased carriage and gut microbiota modulation strategies could reduce Salmonella propagation in farms. Two-hundred and twenty animals from the White Leghorn inbred lines N and 61 were raised together on floor, infected by SE at 7 days of age, transferred into isolators to prevent oro-fecal recontamination and euthanized at 12 days post-infection. Caecal content DNA was used to measure individual Salmonella counts (ISC) by droplet digital PCR. A RNA sequencing approach was used to measure gene expression levels in caecal tonsils after infection of 48 chicks with low or high ISC. The analysis between lines identified 7516 differentially expressed genes (DEGs) corresponding to 62 enriched Gene Ontology (GO) Biological Processes (BP) terms. A comparison between low and high carriers allowed us to identify 97 DEGs and 23 enriched GO BP terms within line 61, and 1034 DEGs and 288 enriched GO BP terms within line N. Among these genes, we identified several candidate genes based on their putative functions, including FUT2 or MUC4, which could be involved in the control of SE infection, maybe through interactions with commensal bacteria. Altogether, we were able to identify several genes and pathways associated with differences in SE carriage level. These results are discussed in relation to individual caecal microbiota compositions, obtained for the same animals in a previous study, which may interact with host gene expression levels for the control of the caecal SE load.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Chickens / genetics
  • Chickens / microbiology
  • Humans
  • Palatine Tonsil
  • Poultry Diseases* / microbiology
  • Salmonella Infections, Animal* / microbiology
  • Salmonella enteritidis / genetics
  • Transcriptome

Grants and funding

Joint program of the Institutes Carnot Santé Animale (ICSA) and Pasteur Maladies Infectieuses (PMI). The PhD of Anais Cazals was funded by Région Ile de France (50%) and the Animal Genetics Division of INRAE (50%). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.