the air cell is on top in these pics, outlined with a sharpie to monitor growth. it's common for them to become detached with shipped eggs, but not likely for eggs that have not travelled. Vertical positioning is fine also, so you haven't done anything wrong. I incubate everything vertically, with the exception of Call duck eggs.
top pic is a chicken egg, probably around day 14ish, 2nd pic is also chicken, probably day 7.
top pic is a chicken egg, probably around day 14ish, 2nd pic is also chicken, probably day 7.
I wouldn't toss any or make any decisions about non-viability just yet unless one stinks. Your candling pics show good spider vein development and I understand with ducklings you can really see some fun stuff later, like tiny web feet
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