Social conflict reduction program for male mice.

Area of Science:

• Laboratory animal science
• Animal welfare
• Ethology

Background:

• Aggression in unfamiliar male mice housed together is a significant welfare issue in laboratory settings.
• Fighting can lead to injuries, death, and euthanasia, impacting animal well-being.
• Social stress can confound experimental results.

Purpose of the Study:

• To implement and evaluate a program aimed at reducing social conflict and aggression in group-housed male mice.
• To improve animal welfare by minimizing fighting-related injuries and losses.
• To reduce the confounding effects of stress on animal research.

Main Methods:

• Daily observation periods were established to identify dominant mice based on specific behaviors.
• Dominant mice were separated from the group when necessary to mitigate aggression.
• A social conflict reduction program was implemented and monitored.

Main Results:

• The implemented program resulted in a 57% reduction in mice reported for clinical signs, death, and euthanasia.
• Aggressive acts between cage mates were significantly reduced.
• Animal welfare concerns related to fighting were demonstrably addressed.

Conclusions:

• The social conflict reduction program is effective in decreasing injuries and loss due to fighting in laboratory mice.
• This simple, humane program can be readily applied to other facilities housing male mice.
• Minimizing aggression enhances animal welfare and reduces experimental variability.