Animal housing
Twenty wild rats (10 male [average weight: 159 g ± 38]/10 female [average weight: 115 g ± 19]) were caught in live capture traps from native forests in Canterbury, New Zealand over a four week period (20 July to 17 August 2016). On arrival at Lincoln University’s research facility (Lincoln, New Zealand), rats were weighed, treated for parasites, sexed and housed individually within cages measuring 48 × 30 × 20 cm high. Housing cages were lined with wood shavings and contained food (i.e. a mix of standard lab chow pellets, fresh fruit/vegetables and seed mix), water, nesting material and enrichment (e.g. cardboard tunnels and boxes). Rats were kept under natural lighting conditions and at ambient temperatures by placing their individual housing cages in an outdoor enclosure that was positioned in a sheltered area of the research compound. All animals were allowed at least ten days to acclimatise to their cages and feeding regime before they were used in trials.