The results of thermal applications to the abdomens of unrestrained, unanesthetized dogs are reported. A silicone rubber envelope through which water circulated at 0°, 10°, 20°, 30°, 40°, or 50°C was applied. Skin surface, subcutaneous, intraperitoneal, intestinal, and colonic temperatures were measured after 90 minutes. Pad applications at 0°, 10°, 20°, and 30°C significantly lowered skin surface and subcutaneous temperatures, while pad applications at 40° and 50°C significantly increased subcutaneous and skin surface temperatures. None of the pad applications had a significant effect on intraperitoneal, intestinal, or colonic temperatures. The findings indicate that a wide range of thermal applications to the abdominal skin of the dog do not alter deep abdominal temperatures.