Physiological adaptations to prolonged fasting in the overwintering striped skunk (Mephitis mephitis)

Area of Science:

• Zoology
• Animal Physiology
• Environmental Science

Background:

• Striped skunks (Mephitis mephitis) undergo physiological changes during winter.
• Understanding these adaptations is crucial for conservation, especially with climate change.

Purpose of the Study:

• To investigate the winter physiology of captive striped skunks under cold ambient temperatures and fasting.
• To analyze body temperature, activity, hematology, plasma biochemistry, and tissue fatty acids.

Main Methods:

• Monitored body temperature (Tb) and activity levels in captive skunks for 105 days of food deprivation.
• Analyzed hematology, plasma biochemistry, and tissue fatty acid profiles.
• Recorded daily torpor bouts and their duration and depth.

Main Results:

• Skunks entered phase II fasting with elevated nonesterified fatty acids and glycerol, indicating preferential mobilization of specific fatty acids.
• Hematological analysis suggested dehydration.
• Activity levels decreased in mid-winter, with most activity occurring in the evening.
• Daily torpor was observed, with deep torpor bouts occurring in the morning and lasting over 3 hours.
• A significant relationship was found between average 24-hour body temperature and ambient temperature.

Conclusions:

• Striped skunks display complex physiological adjustments to winter conditions, including fasting and daily torpor.
• Changes in ambient temperature due to climate change may alter skunk torpor patterns and winter survival.