Simple Genetic Question

I’m not an expert at this, but let me think out loud. The crested is dominant. The blue egg gene is dominant. You only need one of each to have it show. Of course, if they are split for these, they won’t breed true. The molting is recessive. To me, the dominate genes are harder since you don’t know if they are pure or split when that shows up. But Sonoran gave you a big tip. The crested with the bigger crests are pure for that gene, not split. So if you have a choice to make, choose the one with a bigger crest.

The more variables you have, the more chicks you have to hatch to get those variables to show up.

I think my first step would be to cross a rooster from a flock that lays dark eggs, like maybe a Maran or Welsummer with a hen that lays green or blue eggs. Stay away from white birds. You don’t want any white in here at all. It can show up later and mask the mottling. Whether red or black is your choice though if you are going black, I don’t think it matters if there is silver in there or not. If you are going red, I’d try to avoid silver. A lot of black chickens have silver. I don’t know which color you want at the end of the day but the earlier you can get started on that the less you have to eliminate from your flock. The reason I’d always use hens that lay blue or green eggs is that roosters don’t lay eggs. You really don’t know if the rooster has the blue egg gene or not.

In the meantime, cross a mottled with a crested bird. It does not matter which is father or mother. Then take the offspring from that and cross it back to a pure mottled bird. Keep the offspring that is both crested and shows mottling. My purpose in crossing it back is to make sure any bird from this side has the mottled gene. Since it is recessive you need it to be pure to know for sure it is there. If you have a mottled Houdan rooster to start with you are way ahead in the game.

Then take a mottled crested rooster and cross him with a hen that is laying a dark green egg. Take the pullets from that hatch and cross them back with a mottled crested rooster. You should get dark green egg laying mottled crested pullets from this hatch.

These will not be pure for the blue egg gene. Some will be split and some will be pure for not blue. If you choose the ones with the larger crests they might be pure for that. You’ll probably get some different shades of green eggs. Save only the ones that are mottled and that gene is set. That’s why I say recessive is easy. You know if they are pure or not.

You’ll still have to do some work to get that blue egg gene set in the flock. Since it is dominant you can never be sure if the hen is split for it or pure. The rooster doesn’t lay eggs so he will be a question mark. If you mate green egg laying pullets from roosters that hatch from green eggs, you at least have the possibility of getting chicks that are pure for that gene. The only way I know of for sure to know if they are pure for the blue egg gene is to do some test matings. Cross them with chickens you know do not have the blue egg gene and hatch a lot of chicks. The more you hatch, the surer you will be. Raise the pullets from those test matings and see what color eggs they lay. If you get nothing but green eggs from those pullets, the parent is pure for the blue egg gene. If you get a brown egg, they are not pure.

As I said, I’m not an expert and am just thinking out loud. Some experts may shoot holes all through this. There may be easier ways but at least this might be a starting point for your planning.

Good luck and have fun.
 
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If you start with a peacombed blue egger you can keep track of the blue egger gene by the peacombs of the roosters.

For the second generation you have to cross two split mottled animals, else you might lose track of that gene.
Backcrossing to the mottled donor would help the mottling but not the other desired traits

So for example:

cross 1: mottled * blue egger
cross 2: mottled * crest

2nd gen: offspring of cross 1 with peacomb * offspring of cross 2 with crest

3rd gen: take mottleds with peacomb (and crest) ...
 
DURR, in my opinion Henk is one of the top two members on this forum as far as genetics go. Pay close attention to what he says.

Henk, DURR had a fourth trait he was looking for, the dark olive egg color, not just the blue egg gene. I thought it might be better to work on the egg color on one side while setting the mottling and the crest on the other.

The blue egg gene almost always follows the pea comb gene, and the pea comb gene is also “dominant”. As long as you don't have any other breeds in your mix that has the pea comb and the original chicken with the blue egg gene has the pea comb, that is a great way to help pick your roosters from the side that lays the blue/green eggs. You can use it for the hens too but they will confirm it by the eggs they lay. If one or more of your breeds has the rose comb instead of being single combed, then rose with pea makes walnut. Rose is also dominant.

There are other modifiers that can give you some of those weird combs like buttercup, but the two basic comb genes are pea and rose, both dominant. Neither of these genes is sex linked, so each chicken will always have a pair. Maybe this will help. With capital “P” meaning the dominant pea gene, lower case “p” meaning not-pea, “R” being dominant rose and ”r” being not-rose:

PP,rr or Pp,rr gives you a pea comb

pp,RR or pp,Rr gives you a rose comb.

PP,RR or Pp,Rr or Pp,RR or PP, Rr give you a walnut comb.

pp,rr gives you a single comb.

Another thing that can help you with that. The pea comb is not always totally dominant. That’s why I put it in quotes above. If one pea gene is there, you will always see its effect, but it is possible that if only one pea gene is there, it may not be a perfect pea comb. If you have a Pp, you can sometimes get a wonky looking pea comb. I had one like that once. It was definitely a pea comb but it grew out a bit like a single. So just like you should favor the larger crests to try to get the ones that are pure for the crest gene, favor the ones with a perfect pea comb to try to get the ones more likely to be pure for the blue egg gene.
 
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Keep it coming lol!! I need all the research I can get!!

Also to make it simpler could I just use a honduan? They are crested and carry the moltted gene, or what breed would you guys recomend for a good crest? And breed for good molting or speckling genes?
 
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I guess something on egg color. There is one gene that controls the base color. The dominant version is blue. The not-blue version defaults to white. “O” is for the dominant blue. “o” is for the default white. If just one copy of “O” is present, the base color will be blue.

Brown and green are controlled by a lot of other genes. I’ve heard that 13 have been documented but there are certainly several more undocumented genes that affect this. You can think of it as brown or green just being brown on top of the base color.

Base blue + no brown = blue
Base blue + brown = green
Base white + no brown = white
Base white + brown = brown.

In general, if you scrape off the brown or green you can see the base color underneath. Or crack the egg and remove the inside membrane. It’s not totally correct that the brown goes on top of the base color. I’ve seen some different shades of that white when I look inside under the membrane, but some people keep it clear in their heads by thinking of brown paint being sprayed on top of the base.

There are a whole lot of different genes that influence which shade of brown is laid “on top”. Which ones are present and how they go together will determine which shade of brown or green you get.

One of those documented brown genes is sex linked. That means the hen will give it to her sons but not her daughters if she has it. I don’t know the specific effects of that sex linked gene and personally would not worry about it too much. You have some people a whole lot better at genetics than I am on this thread. They may be able to help you with that.

Once you get the brown in the flock, it is real hard to get it out. But with your mix you are likely to get a wide range of shades of green, especially with the Houdan laying a white egg. You’ll just have to hatch a lot of chicks and select for the egg color you want. That becomes your fine tuning after your base colors and patterns are set.
 
Ok, so currently my starting flock consists of EE's already so I would be introducing the other traits to them. I already have one hen that is going to be my main intrests in the breeding because she is crested but then again her crest is small so therfore that gene I don't think would pass if bred back to an uncrested bird. But I believe she could be a base for my "brown" egg gene since she lays a beige egg also with my green egg layers in my flock, and if I am to avoid white in general would I leave out a diluted roo? He's a cream with a pale smokey blue single lace pattern? But I think he might be hom. For the blue gene because all chicks hatched were slate blue with yellow. What do you guys think?
 
Also how could I introduce the sex-link/auto sexing gene?
 
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