Stage Behaviour
0 Normal activity
1 Rigid posture or immobility
2 Stiffened, extended and often arched tail
3 Partial body clonus, including forelimb or hindlimb clonus (seen rarely) or head bobbing
3.5 Whole body continuous clonic seizures while retaining posture
4 Rearing
4.5 Severe whole body continuous clonic seizures while retaining posture
5 Rearing, falling
6 Tonic–clonic seizures, loss of posture, jumping