Which parameter is NOT typically categorized under vital signs?

Muscle tone is not typically categorized under vital signs. Vital signs are crucial indicators of an animal's physiological status and generally include parameters that reflect the immediate functioning of vital body systems. Commonly recognized vital signs include capillary refill time, blood pressure, heart rate, and respiratory rate.

Capillary refill time assesses the circulatory system’s efficiency, often indicating perfusion status. Blood pressure measures the force of blood against arterial walls, critical for understanding cardiovascular health. Respiratory rate provides insight into the respiratory status and can indicate distress or various medical conditions.

In contrast, muscle tone relates to the physical condition of muscle, which can provide information about neurological function and general body condition, but it does not directly reflect the immediate physiological state and is, thus, excluded from the standard list of vital signs. This distinction helps veterinary technicians focus on the most vital indicators of an animal’s state of health during assessment.