Sharing so you know it may not have been anything you did or didn’t do — I also lost an entire batch of 22 call eggs two weeks ago, and I’ve hatched calls many times. Several weren’t fertile, some of the eggs were from girls that just started laying, some had been outside under a broody for several days. 8 made it to day 23. Two internally pipped on day 24, but died before I made safe holes. 2 internally pipped and I began the tedious assists. One died after a whole day of assisting, and still had massive yolk. One survived a long assist, but then died a day or two later. She just never got going.  
 
I set another 14 two weeks later and 10 have made lockdown. Day 24 today!!
So yes, that’s why we call it the Call Duck Challenge. But they are sooooo worth the effort! I also have a girl on eggs, due sometime next week.
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This is the one that lived for a couple of days
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