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Candling Fresh Eggs
Week 1 of Incubation
Weeks 2 and 3
Week 4 of Incubation

Fresh Eggs: Double Yolks
A double-Yolked Egg in a bunch of regular eggs. A double-yolked egg next to a regular egg.
Two normal (duck) eggs, a double yolker, and a goose egg.
Double yolked eggs are usually noticeably larger than other eggs laid by the same type of bird. Egg size is often determined by the kind (species and breed) of bird it is.
The tendency to produce double-yolked eggs may be genetic. It occurs by chance about once every 1000 eggs.
Why won't a double yolked egg produce twins? If this egg had been laid in a flock containing drakes, then it is just as likely to be fertile as any other egg. In fact, it is likely for both yolks to 'hold' the beginnings of new ducklings. While these embryos may both begin to develop, and they may even both make it to term (right up to hatching), they will be unable to get out of the egg because they need to push against the shell to get out. These two will only have each other to push against.

Cesarean sections are not possible with birds.

Click here to see this egg with the yolks enhanced.
Why don't cesarean sections work on birds? Watch a short clip of a double-yolked egg being candled.
Can't watch the movie? Download the Quicktime media player.

farm/candling/double_yolk.txt · Last modified: 2020-05-09 15:02 (external edit)