Group handling using Mus-Bus, a cage-transfer cum enrichment device reduces stress, anxiety and time taken for cage changes and enhances voluntary interaction in C57BL/6NCrl mice

It has been proven that tail-lifting mice can cause stress, anxiety and aversive behaviour, and this finding has made scientists develop less stressful techniques like cupping and tunnel-handling. All these techniques have a disadvantage in that they can only handle mice individually and not in groups. This study produces scientific evidence on the advantages of group handling of laboratory mice for the first time. Group handling using the novel device significantly reduced the time taken for cage changes, a major reason that prevented tunnel-handling from being adopted globally. Shifting mice in groups using a device named \"Mus-Bus\" resulted in significantly lower faecal corticosteroid levels, higher voluntary interaction time and more open field activity when compared with tail lifting and tunnel handling in C57BL/6NCrl mice. Body weights were not different when Mus-Bus was employed with respect to the other groups. This work shows that group-shifting is the next horizon for animal welfare, as this device can revolutionise the handling of laboratory mice to bring in better animal wellbeing.