Final answer:
To obtain an animal's respiratory rate, count the number of breaths per minute, which is indicative of health and is precisely regulated by the brain's respiratory center.
Step-by-step explanation:
To obtain an animal's respiratory rate most commonly, you should observe and count the number of breaths, or respiratory cycles, that the animal completes in one minute. This measurement under non-exertion conditions is typically 12-15 breaths/minute in humans and 15-30 breaths/minute in canines.
The respiratory rate is a vital sign and can be an important indicator of disease, as it may increase or decrease with illness or other pathological conditions. It is controlled primarily by the respiratory center of the medulla oblongata, which adjusts breathing in response to the levels of carbon dioxide, oxygen, and pH in the blood.
Notably, during physical activity, to meet oxygen demands, the respiratory rate can be adjusted by changing the rate of breathing and the volume of air in each breath, which together maintain adequate alveolar ventilation.