How do farmers control whether a chicken lays an eating egg or a reproductive egg and how can they tell which kind is laid?
In: Biology
Hens lay fertile eggs within about 3 weeks of being ‘visited’ by a rooster. She then doles out the semen one egg at a time as she lays a clutch. After laying as many as she wants to incubate, she sits on them, keeping them uniformly ~99° F for 21 days.
Fertile eggs are indiscernible from infertile eggs and can only be proven one way or the other by incubating or cracking them open. Only a trained eye can tell the difference, even by cracking and examining. Noticeable development is only present after 5-7 days at incubation temperatures.
Eggs are generally collected within a few hours of being laid, so there’s normally no danger of finding any development, as they aren’t incubated.
TL;DR: Farmers collect eggs regardless of whether they are fertile or not. Fertilization is absolutely irrelevant, as a normal person couldn’t possibly discern whether the uncracked egg was fertile until day 8 or so of intentional incubation. They look and taste the same either way.
*Somehow deleted part of my response while trying to fix a typo, sorry!
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