Rooster genetics

[Andkingquail]

I recently adopted a moss egger rooster. I'm wondering what egg colors would I get if I crossed him with a maran or Easter egger.

 

[Debbie292d]

Usually it's half and half, and sometimes it blends, like green egg layers might lay olive ones depending who the parents are.

If he's your only rooster, then that will be easy to find out eventually.

 

[Lady of McCamley]

To answer that you have to understand the genetics in your birds and how they interact.

It really depends on the genetics your moss egger has "under the hood." That relies on how carefully controlled the moss egger line was, which is just another hybrid variety of easter/olive egger.

Carefully controlled lines can breed back so that the moss eggers carry genetics for brown shell and blue shells faithfully. Not so carefully controlled lines will have a variety of results meaning the blue shell gene is only passed along 50% of the time, if at all.

The point of easter egger, moss egger, olive egger is the blue shell gene being present so that the result is some shade of green egg. Why...that's the basics of the genetics. The blue shell coloring is controlled by the oocyte gene throwing bile back into the calcite gland so that the shell is colored blue. Open a blue egg and you see blue color inside the shell and outside the shell as the shell itself is blue.

Now brown egg shells are controlled by about 13 different genes, not all of which pass from generation to generation, depending upon the line. That brown shell gene causes a hemoglobin wash to be applied to the outside of the shell as the egg passes down the egg duct. The result is literally a brown painted egg. Open a brown egg and you see white shell inside.

Now the point. Brown wash over blue shell produces shades of green. Brown wash over white shell (absence of the blue oocyte gene) and you get shades of brown.

If you have a carefully controlled olive/moss/easter line, your birds will have 2 blue genes to 100% pass down the blue gene to all progeny. A carefully controlled line will keep the majority of those brown genes so that the brown wash remains bright to produce your best olive, moss colors.

So, *most* olive/moss/easter eggers are hybrids, of a blue shell line over a brown shell line, and carry only 1 blue gene. That means 50% of the time the progeny inherits the blue shell gene. 50% of the time it doesn't. The brown wash genes need refreshing from both sides (rooster and hen) otherwise I find they fade in brown. I typically get middle tone when I breed a darker layer over a lighter layer in the daughters.

Now how dark a green depends on how much brown wash there is over a blue shell. So that depends on the genetics in the lines, which is hard to know with hybrids and definitely if the lines are not controlled.

Now to your question...let's assume your moss egger has 1 blue gene. He might have 2 if carefully controlled, but let's assume he has at least 1 (he might have none if poorly controlled).

Moss egger bred over a generic easter egger (1 blue gene) will produce 25% 2 blue gene progeny, 50% 1 blue gene progeny, 25% no blue gene progeny. The brown wash may be lighter as moss and easter typically are middle to lighter green. You would expect 75% of the time getting greenish egg layers while 25% of the time brown layers of varying shades, but not deep.

Your moss egger (assuming 1 blue gene again) over your Marans will be a nice combination as 50% of the time the progeny will be blue gene with a refreshing of brown wash for deeper greens while 50% of the progeny will be brown layers, typically a nicer brown.

If you are lucky and your moss egger has 2 blue genes, 100% of the time he will pass the blue and you will get varying greens depending upon how much brown refresh you give the progeny.

Good luck on your project.

LofMc

 

[Lady of McCamley]

I should add, if your moss rooster has NO blue genes, then he will only pass along some of his brown shell genes.

Over the easter egger hen (assuming she has 1 blue gene...but you know she has at least one as her eggs are blue/green), you'll get 50% greenish layers and 50% tannish/brown layers.

Moss rooster with no blue genes over your Marans will be shades of brown 100%.

It can be hard to know what you've got unless you do a lot of chicks and have enough sampling to see the occurrence and depth of greens.

Place him over the Marans as a test. If all the daughters lay brown, you can assume your moss egger rooster has no blue genes.

LofMc