A Multiparadigm Approach to Characterize Dominance Behaviors in CD1 and C57BL6 Male Mice

Area of Science:

• Ethology
• Animal Behavior
• Neuroscience

Background:

• Social status and dominance are vital for survival across species.
• Dominance behaviors are diverse and species-specific.
• Mouse models are crucial for studying social behavior, but strain-specific differences in dominance are understudied.

Purpose of the Study:

• To compare dominance behaviors between CD1 and C57BL/6 male mice.
• To investigate the impact of mouse strain on dominance assays.
• To identify reliable measures of social rank in different mouse strains.

Main Methods:

• Four dominance assays were used: agonistic behavior observation, urine marking, tube test, and reward competition.
• Unsupervised machine learning and pose estimation analyzed behavioral data from reward competitions.
• Correlation analysis assessed the relationship between assay results and dominance rankings.

Main Results:

• CD1 mice exhibited significantly higher levels of fighting, urine marking, and tube test resistance compared to C57BL/6 mice.
• Urine marking and agonistic behaviors were the most consistent indicators of dominance across both strains.
• Tube test results for CD1 mice showed poor correlation with other dominance measures, suggesting strain-specific behavioral differences.

Conclusions:

• Mouse strain significantly influences dominance behaviors and assay outcomes.
• The choice of dominance assay is critical for accurate social rank assessment and must consider potential strain-specific effects.
• Standardizing assays across different mouse strains is essential for enhancing the reproducibility of behavioral studies.