Location: Poultry Production and Product Safety Research
Title: Early life exposure to cold stress causes distinct changes in broiler chicken gut neurochemistry and microbiome that persist into later lifeAuthor
Lyte, Joshua - Josh | |
ECKENBERGER, JULIA - University College Cork | |
KEANE, JAMES - University College Cork | |
Robinson, Kelsy | |
SHRESTHA, SANDIP - University Of Arkansas | |
Donoghue, Ann - Annie | |
CAPUTI, VALENTINA - University Of Arkansas | |
DANIELS, KARRIE - Iowa State University | |
LYTE, MARK - Iowa State University |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 6/7/2021 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Objective: Early life stress can cause long-term neuroendocrine adaptations that increase susceptibility to infection in later life. Stress-related neurochemicals produced in the gut play a critical role in enteric colonization and host-microbe bi-directional communication. Young chicks are particularly vulnerable to cold stress, yet it is unknown whether cold exposure during early life may shape neuroendocrine development of physiological sites where foodborne pathogen colonization primarily occurs, such as the gut. We therefore determined if cold stress experienced during the first week post-hatch would cause immediate and long-term alterations in chicken enteric neurochemical concentrations and the microbiome. Experimental design: Broiler chicks at hatch were randomly divided into control or cold stress groups. Chicks from both groups (n=10/group) were euthanized at 3 days/age to assess baseline differences. At days 4, 5, and 6 post-hatch, chicks were subjected to cold stress which consisted of an ambient room temperature of 20oC for 6 hour/day. Birds (n=10/group) were euthanized at 7, 9, and 21 days/age. Materials and Methods: Quantification of neurochemicals in ileum and cecum tissues, as well as ileal and cecal contents were determined using ultra-high performance liquid chromatography with electrochemical detection. qPCR of neurochemical-related genes was assessed in ileal and cecal tissues. 16S analysis of the cecal microbiome was performed. Statement of statistical analyses: Data were analyzed by two-way ANOVA with Dunnett’s or Sidak’s posthoc test, where appropriate. Results: Norepinephrine and serotonin were increased (p<0.05) in the cecal content and tissue, respectively, of cold stressed but not control birds. The main metabolite of serotonin, 5-hydroxyindoleacetic acid, was increased in cold stressed cecal tissue. Ileal tissue and content norepinephrine concentrations diverged (p<0.05) between cold stressed and control birds. Cold stress caused (p<0.05) the down-regulation of expression of serotonin and transporter genes in the ileum, and an increase (p<0.05) in cecal serotonin receptor expression. Cecal microbiome diversity was decreased in cold-stressed chickens at days 7 and 9 of age but recovered at day 21 while differences in microbial composition remained throughout the tested period. Conclusions: Cold stress caused immediate and long-term changes in the broiler cecal microbiome, as well as gut neurochemical concentrations and related gene expression in both the ileum and cecum. Further studies are required to determine the implications of these findings in mediating stress-induced susceptibility to enteric colonization by foodborne pathogens. |