Had this happen with my one hen I kept for her beautiful green eggs. She laid consistent olive green eggs, until all the sudden I started only getting light brown.
I tracked her laying with blue food dye to figure out who was laying olive green.
Both are from the same hen. All I can assume is her blue pigment stopped working for some reason.
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She only lays light brown now.
I've tried this trick on multiple occasions and, on every single try, the dye transferred to other eggs in the nest box that bird chose to lay in. Looked just like this when it happened, too. Based on the very apparent size, shape, and bloom differences between those eggs in that picture, it's pretty clear they're not from the same hen.
Does that happen? Like in the winter they'd just stop? Bc I have been getting less eggs.. I figured all the chickens were just laying less frequently but perhaps both eggers just stopped laying.. they both would lay nearly every day, which always seemed excessive but I was getting more eggs out of those 2 than any other of my chickens (I posted pics if you didn't see them)
Yes, that does happen, especially in older birds but even in younger ones as well. The amount of light they are exposed to in the day triggers different hormones to be released that will stop egg laying and start molt as the days get shorter in the fall, and trigger egg laying again as they days get longer in the spring. They may also quit laying to put that energy toward survival in locations with particularly harsh winters. Some put lights in their coops to prevent this, but that does not seem to make
that big of a difference, at least from what I've seen, giving you maybe a tiny percentage more eggs than you would get without it at best. But that's spoken as someone who has never put lights in my coops for that purpose, so I have no actual experience with it.
Isn't it blue with brown bloom? Blue eggs aren't white with a blue bloom, they're blue throughout.
Brown pigment is applied near the end when the egg is being 'manufactured', just before the true bloom is put on. Blue is intermixed with the shell, itself, and found throughout. Occasionally, you'll find an egg that has brown throughout, but usually that is a one-off and the shell, itself, is not constructed properly as well, either sandpapery or weak in some way. I have heard that there are people out there working with hens that lay eggs with a pinkish-brown tint throughout the shell consistently, but it's been years since I've seen any mention of them and hens that produce that kind of egg are pretty rare to find. The vast majority of brown eggs are a brown coat on a white shell.
A green egg is brown on a blue shell. Brown can be inconsistent in coating, especially between the beginning of a laying cycle and the end. However, the blue shell, at least in my experience, doesn't change much, maybe only getting a tiny bit paler over the lay cycle. My Legbar and all the Easter-eggers I've had over the years have had just as blue of egg shells just before they quit laying to molt in the fall as they did in the spring when they started laying. If you go from getting blue shelled eggs to white shelled eggs, a much more logical conclusion is that one bird stopped laying and another started rather than a radical shift in the egg color from a single bird. The only way to know for sure is to lock your olive-eggers in a pen where no other birds can get in, and see if any eggs are laid within and what color they are. As mentioned above, tricks such as using dye in the vent are prone to giving false conclusions.