What does moist mucous membrane (MM) indicate about an animal's condition?

Moist mucous membranes are typically an indication of a normal hydration status in an animal. When mucous membranes are adequately moist, it suggests that the animal is well-hydrated, and it reflects proper perfusion and healthy physiological function. In a clinical setting, observing moist mucous membranes can usually lead professionals to conclude that there isn't significant dehydration or severe underlying health issues, such as systemic illness or shock, which often result in dry or tacky membranes.

In contrast, if the mucous membranes were dry or sticky, that would indicate dehydration. Conditions such as jaundice, which suggests liver dysfunction, typically manifest through discoloration of the mucous membranes rather than moisture status. Similarly, low blood oxygen levels would not directly affect the moisture of mucous membranes; it might lead to different signs, such as a bluish tint (cyanosis). Thus, the presence of moist mucous membranes serves as a reassuring sign of an animal's general well-being.