What condition do increased heart rate and respiratory rate in animals usually indicate?

Increased heart rate and respiratory rate in animals are often physiological responses to stressors, with pain being a primary concern. When an animal experiences pain, the body enters a state of stress that triggers the sympathetic nervous system, leading to a release of catecholamines such as adrenaline. This reaction elevates the heart rate (tachycardia) and increases the respiratory rate (tachypnea) as the body prepares to either confront or escape from the source of pain.

While conditions such as infection or allergic reactions can also affect heart rate and respiratory rate, they do not universally elicit these responses in all animals or at the same magnitude as pain does. Pain is a primary and immediate reason for such a change in vital signs because it is a direct stressor, while other conditions might involve additional symptoms or mechanisms that do not always correlate with these specific increases. Hence, recognizing pain as a cause of increased heart and respiratory rates is critical in veterinary assessments and interventions.