What day for lockdown on ducks?

[TDIRDAL]

Good morning! I have 10 khaki Campbell's. I started incubating on April 2nd. I've read mixed advice that day one starts on the day you start or a full day after. It's now April 26th, so lockdown is right around the corner. What date based on the starting incubation date of April 2nd should I put them in lock down. They do not look ready yet. Air cells are still dipping.

 

[SilverBirds]

You start counting day 1 24 hours after you've set the eggs. Most duck eggs take 28 days to hatch, and lockdown is three days prior to hatch. Tomorrow day 25, should be the day you lockdown.

 

[Ridgerunner]

Muscovy ducks have an incubation period of 35 days which causes some confusion when talking about ducks, but Khaki Campbells have a theoretical 28 day incubation period. That 28 days is an estimate, it is not unusual for healthy ducklings to hatch a full 2 days either early or late. You want to be in lockdown with the humidity raised before any external pip, so the standard is to lock down 3 days before theoretical hatch after 25 days of development.

When you count you do not say "1" the day you put them in the incubator or under a broody. The eggs do not have a day's worth of development until 24 hours after you put them in. So the day after you put them in is when you say "1". It may be intuitive to start counting when you put them in but that's not the way it works.

April 2 was a Tuesday. Hatch date is Tuesday April 30. Lockdown should be Saturday April 27. An easy way to check your counting is that the day of the week they should hatch is on the same day of the week you first set them. You put them in on a Tuesday, the 28 days are up on a Tuesday.

 

[TDIRDAL]

Thank you so much!