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Updated: May 12, 2026
09:12
The Resident-intruder Paradigm: A Standardized Test for Aggression, Violence and Social Stress
Published on: July 4, 2013
70.7K
Aggression shapes the gut microbiome; a study in rats
Anna Voulgari-Kokota1,2, Joana Falcao Salles1, Regien G Schoemaker1
1Groningen Institute for Evolutionary Life Sciences (GELIFES), University of Groningen, Groningen, The Netherlands.
Plos One
|October 22, 2024
Summary
The gut microbiome influences aggression in male rats. Specific bacteria like Ruminococcaceae and Lachnospiraceae correlate with aggressive behaviors, suggesting the gut-brain axis impacts social challenges.
Area of Science:
- Neuroscience
- Microbiology
- Behavioral Science
Background:
- The gut-brain axis facilitates bidirectional communication between the gut microbiome and the brain.
- Understanding the gut microbiome's role in behavior, particularly aggression, is crucial.
Purpose of the Study:
- To investigate the interaction between the gut microbiome and aggressive behavior in male rats.
- To determine if microbiome composition changes in response to social challenges and aggression.
Main Methods:
- Male rats were housed to establish territoriality and underwent a Resident-Intruder (RI) test to assess aggression.
- Fecal samples were collected before and after the RI test to analyze microbiome composition.
- Bacterial taxa and functional predictions (e.g., betaine reductase) were correlated with aggression levels.
Main Results:
- Pre-RI test abundances of Ruminococcaceae UCG-5 and cTPY-13 negatively correlated with aggression.
- Post-RI test, Clostridium sensu stricto 1 and Bifidobacterium were associated with less aggressive rats.
- Lachnospiraceae was linked to increased aggression and betaine reductase production, potentially via betaine.
Conclusions:
- Gut bacterial communities are responsive to social challenges like territoriality.
- Predisposing microbiome characteristics may predict coping strategies and aggression levels.
- The gut microbiome plays a significant role in modulating aggressive behavior.
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