The Legbar Thread!

[1muttsfan]

Yes, a maran (non-barred) roo over a CL (barred) hen would produce black sex-links, probably olive eggers if she is a CL. Male chicks should have a cream head spot, females not. I thought you were talking about a CL roo over a maran, which would not produce sex-links.

 

[blackbirds13]

I have hatched Legbar X Chocolate Bantam Orps. With the CL dad all my chicks were barred and had head spots regardless of sex. With Choclate dad over CL hen I only had one egg I tried and it's not barred and without a headspot so I assumed female. It is tiny so definitely bantam sized and looks chocolate so far.

 

[ChicKat]

Hello - all Cream Legbar aficionados -

Vote for your preferred Cream Legbar's photo and propell the bird to the winning circle.

https://www.backyardchickens.com/t/...rs-ends-february-28th-at-11-45pm-central-time

Thanks!

 

[LAFreewayChickens]

For a sex link with a CL (barred, gold r/r) roo, you would need to cross with a silver (S) female , then you would have a red sex-link cross not based on barring. To get a barred-base sex link, you cross a non-barred male with a barred female - as in black sex-links.

Barred black chicks have creamy head spots as part of their chick down, and both sexes have them, although they tend to be smaller in females.

I've crossed CL roo x Delaware hen. The females are a light buff gold and usually have some dark spots on their head. The boys are bright light yellow and so far none have had dark spots on their heads.

I'd recommend using hens with not only silver, but also columbian restriction, so you can really see the color differences clearly. Folks in the UK have used light Sussex.

BTW, I'm calling the CL x Del sex link "North Atlantic Stars" .

 

[LAFreewayChickens]

Try this one, far more interesting with implications IMHO: http://www.wattagnet.com/White_leghorn_chicken_sex_ratio_manipulated_with_hormones.html

In a nutshell, the researchers administered corticosterone ( a hormone produced by stress -- either physiolocical or psychological ) to chickens and found that increased levels skewed the hatches to boys.

My thoughts: one explanation would be if there are not enough Roos, hens are stressed because they are fearful of predators. This increased hormone causes them to lay more male eggs therefore more Roos are hatched and those boys will act as a buffer between the predators and the hens.

If this article is valid and the reverse is true ( which may not be the case), having worry-free hens will increase the female chicks or at least keep the ratio at 50/50 instead of 83% roo: 17%pullets that this paper reported.

Last year I hatched 4 boys from 4 eggs that hatched from my flock. My rooster was somewhat of a jerk and I wonder if he WAS the stress to the hens that resulted in the 100% boys. Or I just have really bad luck!

Moral: keep your hens happy! ( I rehomed the roo as he was an awesome flock guardian)

I wouldn't jump to the conclusion that less stressed birds will produce more female chicks. I've followed this research closely.

here's the link to the white leghorn study: http://www.uspoultry.org/research/resproj/PROJ_F027.html

They note that the results were the opposite what was expected. That is, they were the opposite what previous research, albeit mostly in other bird species, has found. In this study they used a very large dose of hormones, which may be the factor leading to the opposite result.

The results aren't published in a peer reviewed journal. Also they don't report any confidence interval or whether they were able to reporduce the result.

I would guess that lower, longer term levels of stress might skew the sex ratio toward females.

Here's a wikipedia link to the hypothesis underlying this vein of research: http://en.wikipedia.org/wiki/Trivers–Willard_hypothesis

 

[1muttsfan]

CL x Delaware = Legware

 

[Sphinx]

Yes, a maran (non-barred) roo over a CL (barred) hen would produce black sex-links, probably olive eggers if she is a CL. Male chicks should have a cream head spot, females not. I thought you were talking about a CL roo over a maran, which would not produce sex-links.

Woohoo! A sex linked olive egger (probably)! That's really quite exciting.

 

[dretd]

I wouldn't jump to the conclusion that less stressed birds will produce more female chicks. I've followed this research closely.

here's the link to the white leghorn study: http://www.uspoultry.org/research/resproj/PROJ_F027.html

They note that the results were the opposite what was expected. That is, they were the opposite what previous research, albeit mostly in other bird species, has found. In this study they used a very large dose of hormones, which may be the factor leading to the opposite result.

The results aren't published in a peer reviewed journal. Also they don't report any confidence interval or whether they were able to reporduce the result.

I would guess that lower, longer term levels of stress might skew the sex ratio toward females.

Here's a wikipedia link to the hypothesis underlying this vein of research: http://en.wikipedia.org/wiki/Trivers–Willard_hypothesis

Valid point, I wasn't really jumping to any conclusions and this was meant to be light-hearted. Here is a link to the full publication for all the science geeks interested in the discussion: http://knavara.myweb.uga.edu/Pinson et al. 2011.pdf Interestingly, they also had increased males in their control group and the injection itself may have influenced male selection (this could be a good thing if you want to maximize male broiler production).

Here is a excerpt from the conclusion with a possible explanation for why their results differed from those previously reported (chronically elevated hormone levels achieved with implants in Peafowl, Japanese Quail and White Crowned Sparrows) : "the chicken model has experienced a high level of inbreeding, and many of its evolutionary strategies may have been artificially selected against. The benefits of adjusting sex ratios in relation to a single acute stressful event are less clear."

Basically, they are noting that the species used in previous experiments are not domestic fowl and so therefore the chicken may differ from the other birds because of the genetic 'manipulation' from the domestication process.

As for the Trivers-Willard Hypothesis, its an interesting hypothesis. Do note that they state that the hypothesis is based on a set of listed assumptions (and it is a hypothesis, not a theory)-- the reverse is true under certain conditions and further, a supporting report states that male bovine blastocysts may be enhanced with the elevated glucose levels of the mother. I am cautious about applying this as broad support of the hypothesis between mammals and avian species because of the obvious differences in reproductive biology.

Still, to keep things lighter: my supposition of happy hens may be wrong. Does that mean that I am spoiling my hens and to get more females to hatch (or any females to hatch) that I should cause chronic stress in my girls through a weight-watchers or boot-camp regime? And here I've gotten rid of my chronic stressor--my jerk of a Rooster (at least he caused me constant stress!). So maybe he didn't cause chronic stress but rather was a good flock protector and therefore reduced the hen's overall stress resulting in all roos? I see potential experiments in the making.

At least in the case of Cream Legbars, the ratio of boys to girls is apparent at hatch! Yay Cream Legbars!

 

[dretd]

Woohoo! A sex linked olive egger (probably)! That's really quite exciting.

I would love to see some of these pictures! I wonder if they would look like Welbars?

 

[Sphinx]

I couldn't find any good pictures of a welbar, so I couldn't say. I think these girls are going to end up looking mostly black, but with some rusty highlights in the feathers. I know it's really tricky to tell how a chicken will look at this age, but I took a close up picture of one of my suspected girls to get an idea on the feather coloring. Oh, and I realized that a couple of them do have feathered shanks, so that trait is stronger than I thought.