Crl cd1 icr

Adult male ICR mice (Crl:CD1(ICR), 8 weeks old at arrival) were purchased from Charles-River Japan. These mice were grouped into 4 or 6 subjects per cageand housed for at least 1 week, but no longer than 1 month, before starting experiments. They remained housed together until all experiments were completed. Animals were housed in a temperature-controlled room with a normal light-dark cycle. Food and water were unrestricted throughout the experiments. All experiments were conducted in accordancewith the Guidelines for Proper Conduct of Animal Experiments by the Science Council of Japan and were approved by the Kyoto University Primate Research Institute animal ethics committee.

A total of 16 adult mice (Crl:CD1(ICR); Charles River, UK) were used for this exploratory study which is carried out as a part of another ongoing study. N = 4 as naive, n = 6 for the TBI group and n = 6 for the craniotomy group were used based on the n values published in our previous study [28 (link)]. Behaviour data was automatically acquired and analysed. For this initial study, only male mice were used following the existing literature and our group’s expertise on the characterisation of male mice brain injury models, based on higher incidence of TBI in the male population (17% in male vs 9% in female, see ref. [29 (link)]). This work should be followed by further studies in female mice in near future. Animals were grouped housed, within the same cohorts from weaning to avoid any fighting and/or aggression.
Animals were housed in independently ventilated cages (IVC; 1300 cm2; Allentown Europe, UK) under controlled conditions 21±1°C, 40–60% relative humidity, 12hr:12hr light: dark cycle (07:00–19:00 light; 19:00–07:00 dark), with standard mouse diet (PicoLab^® Mouse Diet 20; www.labdiet.com) and water available ad libitum. Wood chip bedding with shredded nesting paper, two cardboard tunnel and wood sticks were used. Experimental recording were carried out with animals housed groups of n = 3 or 4 animals.