How can you tell if a rat is dead? - briefly
Check for breathing by watching chest movement or feeling for airflow, and feel for a pulse at the femoral artery; absence of both, together with a rigid body and no reaction to touch, confirms that the rat is deceased.
How can you tell if a rat is dead? - in detail
A rat that has ceased living shows several unmistakable physical cues. Begin by placing the animal on a flat surface and gently probing the torso and limbs. Absence of any twitch, muscle contraction, or reflex when lightly pinching the hind paw indicates a lack of nervous response.
Next, assess respiration. Observe the chest for rising and falling movements; if none are visible, bring a hand close to the nose and listen for airflow. A silent, still chest confirms that breathing has stopped.
Feel for a pulse at the femoral artery, located on the inner thigh. The lack of a detectable beat, even after applying gentle pressure for several seconds, reinforces the conclusion of death.
Examine ocular condition. A live rat typically has clear, moist eyes with a slight shine. Post‑mortem, the cornea becomes cloudy, and the pupils may appear fixed and dilated.
Temperature offers additional evidence. A living rat maintains a body temperature close to its environment, while a dead one cools rapidly. Touch the abdomen; a cold, firm surface suggests death.
Rigor mortis provides a later-stage indicator. Within 1–2 hours after death, muscles stiffen, making the body rigid and resistant to manipulation. This rigidity persists for several hours before dissipating as decomposition begins.
Finally, observe for signs of decomposition: foul odor, discoloration, or maggot activity. These confirm that the organism is no longer alive.
In summary, reliable determination involves:
- Lack of movement or reflexes
- No respiratory motion or audible breath
- Absence of a detectable femoral pulse
- Cloudy corneas and fixed pupils
- Cool, stiff body (rigor mortis) progressing to decomposition
When all these criteria are present, the rat can be confidently identified as deceased.