New Dominique/ee chick. I think it's a girl?

[donrae]

You are adding words to my mouth, but FINALLY giving some empirical data.

(Just because I say, they will all look like that does not mean I am stating that they can be sexed. That is the question. Taking a few words out of the post, and not relating them to the rest of the post is out of context.)

Look the first reply was wrong, and everyone was agreeing. Ok. That is number one. The first post alluded to being able to tell if it is a male under certain heterozygous conditions. This would NEVER be the case. The FEMALE phenotype will be determinable for sure, when only one sex gene is available...but this will not help determine sex, if males look like females too...

It doesn't appear that "dominant" is the right term. Of course there are examples of dosing, however I see NOTHING in the literature for this discussion. That is something that I referred to in saying that chicken genetics seem to be lacking comparatively? A female with ONE dose of a sex-linked dominant gene (100%) has more black on the legs than a male with two copies (100%)? That means that there are OTHER genes involved... IF that is the case, THERE are other subtle things that should be observable. The female with ONE copy, and ONLY one copy will look the same regardless of whether the father was homozygous or heterozygous. Now, using the FEMALE as the standard, you could look for "dosage" dependent differences in leg color:
-My chick has VERY dark legs, possibly darker than a female should have. Could this be caused by the "slate" leg color of the EE? If YES, then I have a male. EE sex-linked "black" leg color gene from mother x Dom "Yellow" Dominant sex-linked gene from father... So, IF there is DOSAGE effect and there are other alleles involved in leg color, you should be able to see subtle differences, as long as you understand genetics.

THIS is something that should NOT be "oh, i've been doing it for years, so I'm right". If the world worked that way we'd all be in trouble.

Now I'm getting insulted and feeling I should walk away from this thread before I go to byc jail. But I guess I'm not that smart before my Diet Coke kicks in.

My first response was not wrong.

Unless both parents are barred, you can't go by the "rules" of barring to sex your birds, sorry.

which parent was which? If the Dom was the father, you'll have to wait for comb, etc around 6 weeks.

If the Dom was the mother, you have a sex linked male.

Please enlighten me exactly what sentence was wrong in your mind. There are only three, it should be easy to narrow down.


My point in saying I've been doing this for years was to show I've seen actual, hands on proof of my research. It's not just theoretical or "popular opinion". I've been blessed to have studied some very knowledgeable folks in the field of chicken color genetics and applied what they told me. I've seen it for myself, not just on paper on the interwebz.

 

[pa2chitown]

...of course, if there are "maternal effect" genes, related to leg color, expressed in the female gamete prior to fertilization, we have even more to add to the discussion.

Something that I am wondering is: sometimes "heat-shock" genes play a role in color. The same genes expressed in rabbit ears, as in the rest of the rabbit, can produce a different color because the ears are not the same temp as the rest of the rabbit. Overall it is a convoluted pathway.
Now, I read that in chickens, males have a higher heart rate. Would this mean they have a higher internal temp, even slightly??? If so, heat shock genes may be the reason for variation in color of the chicks (is this known?)? ....anyway, just a random thought.

 

[pa2chitown]

First, I did NOT want to insult you. My hand was forced...

"If the Dom was the mother, you have a sex linked male"

-that is reversed in chickens (versus human genetics). In chickens the Male has two copies of the sex-chromosome. In humans the Female has two copies of the Sex-chromosome.

Therefore if the Dom was the MOTHER, you CAN ONLY have a heterozygous male.
If the Dom is the FATHER, females will have one copy of the Sex-linked gene/chromosome/allele, for sure.

 

[junebuggena]

This thread may help clarify the leg color sexing for you.
https://www.backyardchickens.com/t/472912/leg-color-genetics

 

[pa2chitown]

....I meant to say, females would have one and ONLY ONE gene/chromosome, for sure.

 

[pa2chitown]

The leg color chart is incorporated into "My" argument. The argument that "dominance' is NOT the correct term if it is dosage dependent and especially if other pathways and other genes are involved.

 

[pa2chitown]

FYI, I have a MS in the field of genetics and have taught "general genetics" to undergraduates.

 

[pa2chitown]

Maybe we are advancing the field of chicken genetics right here?

Quote:
Two points:
-First, in a STRICTLY dominant sex-linked situation, you WOULD be able to sex any offspring that have ONE or TWO copies of that chromosome. Females are a gimme with ONE and ONLY ONE chromosome, can only produce that trait (100% expression, because no other gene present). If they receive it their trait will be expressed the same way regardless. Now males with a purely "dosage dependent" sex-linked dominant heterozygous situation will produce 50% of the dominant gene and 50% of the other. The "dosage" will be ONLY 50%. This is key, since NOW you would expect the males to have less yellow (in this situation)...(hypothetically)
- Secondly, If some other genes (autosomal) are influencing the trait (most likely, although heat-shock and/or maternal genes could). Knowing THIS can aid in sexing the offspring of heterozygotes but it is essentially the same as #1. A dominant pathway involving several genes will not produce as much product and should be visible.

 

[junebuggena]

First, I did NOT want to insult you. My hand was forced...

"If the Dom was the mother, you have a sex linked male"

-that is reversed in chickens (versus human genetics). In chickens the Male has two copies of the sex-chromosome. In humans the Female has two copies of the Sex-chromosome.

Therefore if the Dom was the MOTHER, you CAN ONLY have a heterozygous male.
If the Dom is the FATHER, females will have one copy of the Sex-linked gene/chromosome/allele, for sure.

With the way the barring gene works, the hens can only pass their barring gene to their male offspring. That is why we call the barring gene 'sexlinked'. If the Dom was the mother, and the rooster was not barred, then only the male chicks would have the head spot indicating the presence of the barring gene.
Dominique roosters have two copies of the barring gene, and will pass one copy to each of his offspring, regardless of the chick's gender. You will not be able to sex the chicks at hatching, unless you are really good at vent sexing.
Leg color genes are very complicated. This article may help you understand just how complicated leg color genes can be.
http://www.edelras.nl/chickengenetics/mutations2.html#gen_mut_leg<br><br>W

 

[pa2chitown]

This is the first chick I've hatched in about 30 years (other than the one I saved from Virology course at about day 17, and gave away). "He" will grow up to displace his father in governing the small flock. He is half Dom and half EE (Americauna?).

Thanks to EVERYONE who talked through this conclusion that he is a rooster. His legs are WAY too dark to be a female with a single sex-linked chromosome (unless, of course, his EE mother influenced color due to "maternal gene" protein in the gamete).

Thanks everyone. I will keep track and post updates.

Agree or disagree? I am moving on....

Thanks again!