Cats lifting kittens by scruff of neck

[MargeB]

Why do kittens go all limp and seem to become 'comatose' when this happens? What is the physiology involved?

[dmsjps]

Dunno Marge, but while you're waiting for a reply, why not pop over to ChatterBank and post your piccie? Did you not see my posting that several people were interested? Ya never know either Marge, if you post yours, others might post theirs and you could end up one very happy guy!

[peanut]

they go all limp because being picked up by the scruff of thier neck releases a chemical called endorphans which is like a drug to the cat. it actually paralyzes them until they are let go.

[Tim Baxter]

It's an innate reflex suited to being picked up by a parent and carried (silently) away from danger.  All animals have this reflex especially so of those that still have enough skin to hold on to.