Hyenas, jako savci, mají uzavřený cirkulační systém. V uzavřeném oběhu je krev obsažena v síti krevních cév, včetně tepen, kapilár a žil. This allows the blood to be pumped efficiently throughout the body to deliver oxygen and nutrients to the cells and remove metabolic waste products. The circulatory system of a hyena consists of a four-chambered heart, similar to other mammals, with distinct chambers (two atria and two ventricles) that facilitate the separation and controlled circulation of oxygen-rich and oxygen-depleted blood. Srdce pumpuje krev přes cévy a zajišťuje její konstantní oběh v těle. Overall, the closed circulatory system of hyenas enables the proper transport of substances, gas exchange, and maintenance of homeostasis within their bodies.
