A long-standing problem: mice can be aggressive.
This article hasn’t received the attention it deserves: Gaskill, Garner, Winnicker, Pritchett-Corning, 2017, Lab Animal
Aggression in lab mice is a problem for research. In this paper, the team assessed the factors that are known to influence mouse aggression.
What they concluded was, "In terms of practical recommendations to reduce aggressive wounding in the home cage, tail tattooing [Labstamp] is recommended over ear notching and late weaning should be avoided".
Although the choice of identification method was not specifically addressed within the variables analysed, those with Labstamp tail tattoos did show statistically significant reductions in aggression. The team do point to possible causes:
"Painful, frightening and aversive stimuli are routinely imposed on laboratory mice. Even standard procedures, such as ear marking, can be painful to mice, and mice lifted by the tail (a routine handling technique) avoid contact with humans and are more anxious when compared with mice lifted by using a tube."
The Labstamp tail tattoo can be read on each mouse in the cage. This reduces the need to pick up mice to read the ear mark and it is makes the use of tube / tunnel handling easier as the right mouse can be ushered into the tube quickly and the ID can be read in the tube.