What hormone is released in dogs during fights or threatening situations?

The correct answer is epinephrine, which is also known as adrenaline. During fights or threatening situations, the body activates the "fight or flight" response, which involves the release of epinephrine from the adrenal glands. This hormone prepares the dog to either confront the threat or flee from it. It increases heart rate, elevates blood pressure, and boosts energy supplies by mobilizing glucose from the liver. These physiological changes help enhance the dog's physical performance, allowing it to react quickly and effectively in a stressful situation.

Cortisol is another important hormone involved in stress responses, but it is released over a longer duration and serves to maintain energy supply and manage stress rather than immediately prepare for action. Testosterone, while associated with aggression and reproductive behaviors, is not directly responsible for the acute response during fights or threats. Adrenaline is the same hormone as epinephrine, but the preferred terminology in many scientific contexts is epinephrine, hence the focus on this term for clarity.