Refining In-Cage Enrichment for Specialized Mouse Scenarios

Area of Science:

• Laboratory animal science
• Animal behavior
• Animal welfare

Background:

• Environmental enrichment is crucial for laboratory animal welfare, promoting species-specific behaviors and mitigating abnormal repetitive behaviors.
• Assessing the effectiveness of enrichment is vital for refining animal care protocols.

Purpose of the Study:

• To develop and apply a scoring system for objectively evaluating environmental enrichment in singly housed mice.
• To assess the efficacy of selected enrichment items in reducing abnormal behaviors.

Main Methods:

• A scoring system was developed to quantify the usage of enrichment items by singly housed mice.
• The system was applied to evaluate enrichment for repetitive food shredding in CD-1 mice and focal auricular trauma in BALB/c mice.
• Scoring criteria included enrichment use, nest incorporation, and reduction of abnormal behaviors.

Main Results:

• Manzanita sticks and running wheels reduced repetitive food shredding in CD-1 mice, with manzanita sticks chosen for practical reasons.
• Gnawing items decreased focal auricular trauma associated with ear tags in BALB/c mice.
• The scoring system provided objective data on enrichment effectiveness.

Conclusions:

• A standardized scoring system enables objective assessment and selection of environmental enrichment for specific needs in laboratory animal care.
• This approach enhances animal welfare by effectively redirecting abnormal behaviors and improving the evaluation of enrichment strategies.