Age, experience and genetic background influence treadmill walking in mice

Area of Science:

• Neuroscience
• Biomechanics
• Animal Models

Background:

• Treadmill locomotion is a common method for mouse gait analysis.
• Treadmill walking differs from overground locomotion and is sensitive to testing conditions.
• Understanding factors influencing treadmill gait is crucial for accurate motor performance assessment.

Purpose of the Study:

• To investigate the impact of age, genetic background, and repeated trials on mouse treadmill locomotion.
• To identify how these factors affect gait parameters such as stride length and frequency.
• To provide guidance for optimizing experimental design in mouse gait studies.

Main Methods:

• Analysis of gait parameters in C57BL/6J mice across different ages.
• Evaluation of gait changes in response to repeated treadmill trials with varying intervals.
• Comparison of treadmill gait patterns across eight different inbred mouse strains.

Main Results:

• Aging mice (1-6 months) exhibit longer, less frequent strides, linked to size and weight changes.
• Repeated trials lead to modified gait patterns, including shorter swing phase and greater duty factor.
• Short retest intervals (3 min) result in shorter, more frequent steps, with variability based on trial history.
• Significant variations in stride length and frequency were observed among different inbred mouse strains.

Conclusions:

• Age, genetic background, and trial repetition are critical variables influencing mouse treadmill gait.
• These factors must be carefully considered to ensure reliable interpretation of motor performance data.
• The findings support further mechanistic studies and inform the design of robust mouse gait analysis experiments.