Warm ears, paws, or body
Lethargy or unusual tiredness
Loss of appetite
Hiding or reduced activity
Shivering
Rapid breathing
Dehydration
Glassy eyes
Weakness
Elevated rectal temperature above 102.5°F (39.2°C)
Temperature of 103°F (39.4°C) or higher is concerning
Temperature of 104°F (40°C) or higher needs urgent veterinary care