Hatching
Pekin duck embryos take around 28 days to develop in the egg at 99.5°F (37.5°C) and 50-75% humidity. A heartbeat can usually be seen by the third day of incubation when candling the egg.
The eggs must be regularly turned during incubation. This occurs in nature when the female duck shifts her position while sitting on the eggs. For artificial incubation, machines are available which will constantly turn the eggs.
When being artificially incubated, the eggs are moved to a "hatcher" three days before they are due to hatch. This has a slightly lower temperature and higher humidity which increases the survivability of the hatchlings while their protective down develops.
Compared with other birds, duck eggs are relatively easy to hatch as they are very forgiving of variations in temperature and humidity.
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