A. Postural reflex |
0: When suspended by the tail, the animal extends both forelimbs toward the floor |
1: Failure to extend the right forepaw fully, with or without wrist flexion |
2: The animal flexes the right forepaw, and the shoulder touches the thorax |
3: The animal rotates the body to the side of the affected forepaw, with a head-to-tail tendency |
B. Circling motion |
0: Normal, straight-line locomotion |
1: Open circling to the right side, alternating with locomotion in a straight line |
2: Open but persistent circling to the right |
3: Closed and persistent circling (the animal turns consistently around its vertical axis, with the hindlimbs staying at the same place) |
C. Falling to the contralateral side |
0: Absence of falling |
1: Mild, apparent fall. The mandible does not touch the floor |
2: Expressive fall (the right shoulder and mandible touch the floor) |
D. Placement of the right forelimb during locomotion |
0: Normal (the rat can use the forelimb well, step-by-step) |
1: Placement of the right forelimb is somewhat hesitant, as if the rat is walking with a “limp” |
2: If the rat moves (circling), then the right forelimb is dragged and stays under the thorax |
E. General state of alertness or consciousness |
0: The rat walks spontaneously and responds promptly to different stimuli (e.g., touch, sound, etc.) |
1: If undisturbed, then the animal stays quiet but responds or moves when stimulated |
2: The animal does not move at all, even when touched. It stays prostrated, apparently stuporous, and does not react when touched |