Which sign would indicate escalation from mild to more severe heat distress?

• A. Slight decrease in performance.
• B. Normal mucous membranes.
• C. Rectal temperature rising toward 106-108 F and uncontrolled panting.
• D. No signs.

Answer: (C)

As heat distress progresses, the key indicator is the body’s core temperature rising into the range of heat stroke, paired with a failure of normal cooling. A rectal temperature approaching 106–108 F shows the dog is no longer just uncomfortable—it's entering a dangerous state where organs can be damaged if not treated immediately. Uncontrolled panting reflects the body's overwhelmed thermoregulation and signals urgent need for cooling and veterinary care. By contrast, a slight drop in performance can be an early sign, normal mucous membranes don’t indicate worsening, and no signs means no distress.