The "Ask Anything" to Nicalandia Thread

[kurby22]

I need help with some genetics - I had a breeding pair of bobtail Cochins and tonight I found my pullet dead :-( I am wondering if I can still use the rooster and eventually get back some bobtail chicks? I know they are recessive genes and the calculator doesn’t really handle it either, to my novice eye. If I have a black or a blue Cochin hen, could f2 babies be bobtails? I’m so upset, she was a really special girl. I think she may have been egg bound

@NatJ I've read that bobtail is sort of complicated so I don’t wanna just make a mess of things! Thanks.

 

[SourRoses]

Oh no, I'm sorry @kurby22
It extra-sucks when it's one of your favorites

 

[kurby22]

Oh no, I'm sorry @kurby22
It extra-sucks when it's one of your favorites

Thanks it truly does extra suck!! She was full of personality and so pretty I want more just like her and was super excited to start collecting eggs from her soon

 

[NatJ]

I need help with some genetics - I had a breeding pair of bobtail Cochins and tonight I found my pullet dead :-( I am wondering if I can still use the rooster and eventually get back some bobtail chicks? I know they are recessive genes and the calculator doesn’t really handle it either, to my novice eye. If I have a black or a blue Cochin hen, could f2 babies be bobtails? I’m so upset, she was a really special girl. I think she may have been egg bound

@NatJ I've read that bobtail is sort of complicated so I don’t wanna just make a mess of things! Thanks.

I don't know much about bobtail either.

But for any recessive gene, if you cross one parent who has it (your rooster) with one parent who does not (hen), you get F1 chicks that carry the gene. Breeding them to each other gives F2 chicks with about 1/4 showing the recessive gene. Or doing a backcross of F1 chicks back to the parent gives about 1/2 chicks that show the recessive gene.

When you are working with more than one recessive gene, the numbers get worse pretty fast. Two recessive genes would appear together in about 1/16 of chicks in the F2 generation, or 1/4 of the chicks in the backcross generation. Three recessive genes would be expected to appear together in only about 1/64 of F2 chicks, or 1/8 of backcrossed chicks.

When there are sexlinked genes involved, it can be easier or harder depending on which gender has which genes.

If you have the option of black cochin or blue cochin hen, I would use the black one (because then you don't have the blue gene making things any more complicated than they already are.) If you have to use a blue hen, I would cross her to the bobtail rooster and only breed from chicks that show black (not blue).

As regards information specifically about bobtail, I found this:
https://www.cochinsint.com/uploads/8/8/2/1/8821267/ci_-_bobtail_cochins.pdf
It's from 2013, and I can't find any updates on the breeding trials that are mentioned.

If that is right, the actual bobtail gene should be a sex-linked gene, and I think the "blackred" color they mention might be Birchen chickens with red instead of the silver.

A Birchen hen might be a good choice, although it could be even better if you found one showing gold or red instead of the silver (I'm not sure of the correct variety name in Cochins: maybe Gold Birchen or Brown Red?)

If you find the "right" hen to work with, and if the actual bobtail gene is sex-linked, you would get bobtail females in the first cross to your rooster, and breeding them to their father would give pure bobtails. Breeding the F1 pullets to their brothers would give some bobtails in both genders, perhaps as high as 50% bobtails.

Note, the previous three paragraphs involve some guesses and assumptions, and I may be wrong in one way or another. If I am wrong, hopefully someone else will set us both straight.

@nicalandia do you know more about bobtail? Both the gene, and what other genes are required (E^R Birchen? does gold vs. silver matter?)

 

[kurby22]

I don't know much about bobtail either.

But for any recessive gene, if you cross one parent who has it (your rooster) with one parent who does not (hen), you get F1 chicks that carry the gene. Breeding them to each other gives F2 chicks with about 1/4 showing the recessive gene. Or doing a backcross of F1 chicks back to the parent gives about 1/2 chicks that show the recessive gene.

When you are working with more than one recessive gene, the numbers get worse pretty fast. Two recessive genes would appear together in about 1/16 of chicks in the F2 generation, or 1/4 of the chicks in the backcross generation. Three recessive genes would be expected to appear together in only about 1/64 of F2 chicks, or 1/8 of backcrossed chicks.

When there are sexlinked genes involved, it can be easier or harder depending on which gender has which genes.

If you have the option of black cochin or blue cochin hen, I would use the black one (because then you don't have the blue gene making things any more complicated than they already are.) If you have to use a blue hen, I would cross her to the bobtail rooster and only breed from chicks that show black (not blue).

As regards information specifically about bobtail, I found this:
https://www.cochinsint.com/uploads/8/8/2/1/8821267/ci_-_bobtail_cochins.pdf
It's from 2013, and I can't find any updates on the breeding trials that are mentioned.

If that is right, the actual bobtail gene should be a sex-linked gene, and I think the "blackred" color they mention might be Birchen chickens with red instead of the silver.

A Birchen hen might be a good choice, although it could be even better if you found one showing gold or red instead of the silver (I'm not sure of the correct variety name in Cochins: maybe Gold Birchen or Brown Red?)

If you find the "right" hen to work with, and if the actual bobtail gene is sex-linked, you would get bobtail females in the first cross to your rooster, and breeding them to their father would give pure bobtails. Breeding the F1 pullets to their brothers would give some bobtails in both genders, perhaps as high as 50% bobtails.

Note, the previous three paragraphs involve some guesses and assumptions, and I may be wrong in one way or another. If I am wrong, hopefully someone else will set us both straight.

@nicalandia do you know more about bobtail? Both the gene, and what other genes are required (E^R Birchen? does gold vs. silver matter?)

Thank you! You always explain things so well! The black hen I have came from two blues but the rooster is not a good blue—he’s like part birchen or blue with a LOT of gold leakage. So his daughter actually has some gold leakage as well in the hackles. Would this be a possible option with the gold leakage? Obviously a fully gold birchen would be better…it’s just the most gorgeous color and the feathers truly are beyond soft and fluffy. She had laid some pullet eggs so they’re probably not fertile, but I put them in the incubator anyway

 

[NatJ]

Thank you! You always explain things so well! The black hen I have came from two blues but the rooster is not a good blue—he’s like part birchen or blue with a LOT of gold leakage. So his daughter actually has some gold leakage as well in the hackles. Would this be a possible option with the gold leakage? Obviously a fully gold birchen would be better…it’s just the most gorgeous color and the feathers truly are beyond soft and fluffy. She had laid some pullet eggs so they’re probably not fertile, but I put them in the incubator anyway

Yes, that pullet might be a good choice to start with, especially since you already have her. That means you don't need to wait to buy a new hen, or buy chicks and wait for them to grow up before you can start breeding.

Hatching some chicks from her, with your bobtail rooster, should definitely give an idea of how easy the project will be-- if they show bobtail traits you are close to what you want, if they look like normal blacks you have a more difficult situation but crossing the daughters back to the bobtail rooster would be a good next step.

I also realized: if the bobtail gene is on the Z sex chromosome, it may not matter whether there is gold vs. silver in the hen you use.

 

[JosieMaeChickens]

What do you know about red sex links? We want to start breeding them. We are considering golden Comets or ISA Browns. What do the parents have to be to in order to make these hybrids?

 

[NatJ]

What do you know about red sex links? We want to start breeding them. We are considering golden Comets or ISA Browns. What do the parents have to be to in order to make these hybrids?

To get the really high production, you need the specific parent lines used by the hatcheries, which they do not sell.

If you just want color-sexable chicks, a Rhode Island Red rooster is the most common father breed.

To get the common red females who have white feathers in their wings & tails, you need an all-white mother with the right genes. Not all white breeds will work. Rhode Island White is commonly mentioned as the mother breed for the commercially available ones. White Rocks or White Wyandottes might work or might not. White Leghorns will not work.

If you want color-sexable chicks but don't care about exact details of color, use a mother that has a lot of silver and some black. Good choice could include Delaware, or Columbian Wyandotte, or Columbian Rock, or Light Sussex. Using a hen that has some black will mean the chicks grow some black feathers too, so the sons will loook Columbian and the daughters will look rather like Rhode Island Reds (not quite the same appearance as ISA Browns or Golden Comets, but the pattern of red females/white males will be correct.)

 

[3KillerBs]

What do you know about red sex links? We want to start breeding them. We are considering golden Comets or ISA Browns. What do the parents have to be to in order to make these hybrids?

Welcome to BYC.

As @NatJ said, to get the same sort of commercial sexlinks that hatcheries use you have to have the specially-selected production lines for parents.

You have to have them every generation -- maintaining those two separate parent lines pure as well as crossing them to get the sexlinked chicks because the sexlinkage doesn't work in subsequent generations.

 

[MoaHula]

Hello Nicalandia,
First, thank you for your great input on the forum. I have learned much from you.
So, I have raised chickens for multi-colored egg production and sale for a few years now. I am starting on a new breeding program this year which includes the Ayem Cemani. One of the first phases of that (besides bringing in additional lines) is to test my current 3 beautiful birds for Fibro 1 or 2.
I have one AC rooster and two hens.
Now, I see that you suggest using Ameraucana for testing but I do not have that breed. What I have are: Silverudd's Blue, Welsummer, Black Copper Marans, Cuckoo Maran, Beilefelder, Anconda, Silver Wyandotte, and multiple olive eggers.
I have tried using the Kippenjungle.nl website to identify a suitable pairing but was unsuccessful.
I know you did say to use Slate or Willow shanked birds but could you tell me if any of these will work?
Thank you.