Further reserch via wikki : This may not be clinical hypnosis, but instead a case of tonic immobility. Instead of a hypnotic state, the chicken's reactions are more akin to a turtle moving into its shell, or a deer freezing from a spotlight – a defensive mechanism intended to feign death, albeit poorly.[1] :shock:
The first known written reference for this method came in 1646, in Mirabile Experimentum de Imaginatione Gallinae by Athanasius Kircher.
Another technique of hypnosis is to hold the chicken face up with its back on the ground, and then run your finger vertically downwards from the chicken's wattles to just above its vent. The chicken's feet are exposed, which allows easy application of medication for foot mites, etc

19 . To wake up the chicken, clap your hands or give the chicken a gentle shove.
One can also hypnotize a chicken by mimicking how it sleeps - with its head under its wing. In this method, you hold the bird firmly, placing its head under its wing, then, gently rock the chicken back and forth and set it very carefully on the ground.

07 It should stay in the same position for about 30 seconds.[2]