Duck egg sunk but moved 2 days ago

[Jerri85]

hello. I have one duck egg that my broody hen has been sitting on. It has been developing fine. I am not sure of what day we are on, bc it was unexpected brood from a hen but I am guessing day 26ish?.. a few days ago I could see movement in the egg and knew it was alive, now its so big I cant see anything but the air sac. I did a float test and the egg sunk to the bottom, everything I have read about that just says it was never viable, but I have watched this egg develop and move for weeks so I know it was fertilized and growing. Plus since air sac looks good, why did it sink? What does it mean?

 

[Pyxis]

So, I'm going to start right out and say that the float test is crap and there's no reason to ever use it. I don't know why people use it so much (not aiming this at you, I mean the people who perpetuate its use). Anything it can tell you, you can learn from candling, and it also is often wrong.

As is the case here - it's telling you that that egg is 'bad' and was never viable, and you know it was. Someone just last week did the same thing and the float test 'told' them the egg was bad, so they cracked it open - and killed the live chick that was in there.

Secondly, if you do want to do the float test, it should never be done until the egg is actually overdue. Since you're not even to the hatch date yet, I wouldn't be doing it. For now, just let the hen have it. If it doesn't hatch in a week, maybe try again, although at that point candling should be able to tell you whether it died or not.