2.4 Environmental enrichment
Following weaning ArcKR and WT mice were exposed to an enriched environment for 8-10 weeks. Mice were housed in larger cages (rat cages) with increased numbers of littermates per cage on a 12:12 hour light and dark cycle, with food and water ad libitum. Male and female mice were kept in separate cages. The environment of the mice was further enriched by the provision of a variety of toys including running wheels, tunnels, small structures to hide in and mezzanines as described in (Privitera et al. , 2020). Except for the provision of running wheels, which were permanently available to the mice, the selection and arrangement of toys was changed twice a week to ensure continued enrichment. Mice were also provided with increased amounts of nesting material to allow the expression of species typical nest building behaviour. Mice were given sesame seeds which were distributed around the cage to encourage foraging behaviour.