That's news to me - and I worked 50 years in blue collar jobs.
The “head” part I have heard before.
But not sure how the “chicken” got involved.
Of course, for the last 20 years everyone I worked with spoke a foreign language.
Maybe they were all talking about the chicken?
When chickens walk they bob their heads. Moving on...
It’s based on the motion of a chicken eating, head bobbing up and down.