But to the question you pose...
Circumference, that's lineal, i.e., we're talking lengths.
Hen's eggs, there is a known entity, even down under.
But zhikken feed pellets, well, they have been known to be quite amorphous.
So the question seems to become, what is the length of your typical zhikken feed pellet?
Oh, that's not an easy question. But a most excellent one to raise.
From what i've seen, the length of a zhikken feed pellet depends entirely upon multiple factors, only a few of which have been documented to date.
Looking at the research of Dr. Fortyforone, she seemed to have determined that the average length of a zhikken feed pellet is about the same as sixteen bits of Corperincus Disdirectium.
But that level of determination of the length of a zhikken feed pellet was not good enough for many.
So they asked for more resolution in future research....
And we got it...
(OK, I'll go away quietly now....)