Always remember to toe punch or
mark your ducklings from this type of a breeding program because a duckling
that does not have a crest does not necessarily mean that duckling does not
carry the crested gene.
That Is from my source that u gave me the link to
I did not provide that link.
Here is the correct information.
What is pertinent to this conversation is BOLDED
http://www.metzerfarms.com/Articles/CrestedDucksUnusualBrains.pdf
Also this:
http://en.m.wikipedia.org/wiki/Crested_duck_(breed)
The domestic Crested Duck is a duckbreed descended from the Mallard. It has its appearance because it is heterozygousfor a genetic mutation causing a deformity of the skull. As a result, when a pair of crested ducks breed, the young sort out in the usual 1-2-1 ratio:-
25% are homozygous for the normal allele of this gene and so have no crest and if bred together their offspring will never have a crest.
50% are heterozygous for this gene and hatch with a crest of varying sizes.
25% are homozygous for the crestedallele of this gene and die from exposedbrain without hatching, as it is lethal in homozygous form.
If a crested duck and a non-crested duck breed together, the resulting ducklings would be expected to be 50% crested and 50% non-crested.