Table 1. Comparison of daily torpor, with facultative, and obligative hibernation.
| Daily torpor | Facultative hibernation | Obligate
hibernation |
|
|---|---|---|---|
| Trigger | Calorie deficit | Photoperiod / ambient
temperature |
Season |
|
Mean minimum temperature reached
( Ruf & Geiser, 2015) |
17°C
(for a 30g animal) |
4°C
(range from -2 to 30°C ) |
|
|
Minimum VO2
( Ruf & Geiser, 2015) |
~0.24 mL O2 g−1 h−1 (~40% of
BMR) |
~0.04 mL O2 g−1 h−1 (~6% of BMR) | |
|
Mean torpor bout duration
( Ruf & Geiser, 2015) |
6–7 hours
(for a 30g animal) |
>120 hours | |
|
Nutritional state (
Carey
et al., 2003;
Huang et al., 2021; Kurtz & Carey, 2007; Ruf & Geiser, 2015) |
Calorie deficit / Weight loss | Reduced body mass (at least
in Syrian golden hamsters) |
Increased
adipose stores |
|
Influence of gonadal function
( Barnes et al., 1988; Jansky et al., 1984; Mzilikazi & Lovegrove, 2002) |
Testosterone inhibits daily torpor
in Saccostomus campestris No known direct effect on gonadal function |
Preceded by gonadal involution, blocked
by testosterone, and followed by gonadal maturation |
|