Table 2 Stressors employed in randomised daily sequences during the UCMS protocol.
Stressor | Definition |
|---|---|
Temperature | Standard temperature of 21 °C was unpredictably set either at 12 °C or at 30 °C for 3 h |
Short day | 4 h photoperiod (L:D = 4:20 h) |
Short night | 21 h photoperiod (L:D = 21:3 h) |
Chased by humans | An experimenter physically chased animals for 5 min, repeated every 30 min for 4 h in total. Animals were seized and released several times within each 5 min session |
Wind | An oscillating fan was placed in the middle of each chamber for one day |
Food deprivation | Food, but not water, was removed from each pen overnight (12 h) |
Wet litter | Litter was saturated with a water hose without animal removal and left wet overnight |
Nest box removal | Nest boxes were removed from the pen for 5 h |
Social mixing | Animals from different pens and chambers were mixed randomly in a separate chamber with 4 pens in it for 2 h |
Isolation | Animals individually constrained in a transportation box (0.45 × 0.25 × 0.25 m) for 2 h |
