Shadrach's Ex Battery and Rescued chickens thread.

[Perris]

to exist in isolation

that drives speciation certainly, but isolation is the exception rather than the norm for life on earth, isn't it? E.g.
"hybridization between domesticated and wild populations is common in nature and thus could mislead the estimation of their genetic differences [32, 33]. Domesticated chickens have been affected by gene flow via hybridization with other RJFs and jungle fowl species over thousands of years [34, 35]." Wang et.al. Large-scale genomic analysis reveals the genetic cost of chicken domestication https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-021-01052-x

 

[BDutch]

Well if that isn't the truth! But generally speaking ecosystems tend to exist long enough for certain phenotypes to stay the same for while. Or millions of years, looking at you coelacanth and horseshoe crab . I do think I have read you writing you do add new breeds every once in a while, so guess it's always changing how exciting!

That's how I understood it too. In your specific flock I would think most should be heterozygous and the specific rooster just didn't inherit that gene.

But you do raise an interesting question. I only know the theoretical stuff which suggest that Polish are homozygous well all the other smaller crests are heterozygous. I have seen some small variation in crest size, as the farther my flock went from their Polish ancestor the smaller the crests became. But this homozygous and heterozygous view seems to suggest cream legbars, brabanters and spitzhauben are heterozygous. So maybe there are indeed multiple genes going on behind the scenes, or the smaller crests of these breeds could be an ancestor version of the Polish one and are therefore still homozygous?
View attachment 4159511
Showing this image from a paper that created a taxonomy of old Dutch breeds. Sadly it doesn't show other European breeds. there are 2 Polish breeds listed as Polish bearded tends to refer to Padovana, which is a seperate breed.


Don't know much about double spurs yet. But I do know they are very hard to psot on females. So somewhere you did get a double spurred chicken and if that was a long time ago then its only been inherited by the hens so far, until now that is. If you are able maybe check your hens and see if you can spot an indication of double spurs?

The scheme is nonsense. One example:
Schijndelaar is a new breed (around 2010) while Dutch is a very old one (recognised features around 1910 but in fact much older) . So Dutch cant be a descendant of Schijndelaar. The layer and broilers were bred after WWII.

 

[BDutch]

I don't know. I choose to try to ensure that each pullet/hen gets a chance to reproduce her genes and those of whoever she mated with, rather than to continue a particular trait. Would that be landrace or not? I'm trying to put Darwin in the driving seat while maximising everyone's chances.

I you want to establish a group best fit for your garden and the way you feed them, you don’t need to bring in new genes. The finches with the large beaks who are able to eat the nuts didn’t come from a large gene pool.

 

[BDutch]

When actively selecting for bigger crests in roman times they would have crossed individuals with homozygous crests, but those are small compared to today's standards. Those primitive smaller homozygous crests are probably the crests we see today in the Brabanter and Spitzhauben. The Polish is simply the 2005 broiler in terms of crests.

Not in roman times but later as a hobby for the rich.
From www: Although the exact origins of the Polish remain somewhat mysterious, pastoral paintings from the 15th-century in the Netherlands help solidify its history as a fancy bird of European origin.
There is a Dutch type with a large crest too. The exact origin of the ‘Hollands Kuifhoen’ or ‘Crested Dutch’ is not known. It is considered to be an originally Dutch breed, but possibly has Polish roots and is certainly originally from Asia. It is depicted in Dutch paintings from the beginning of the 17th century, but it may have been present in the Netherlands for longer.

Article with more information from a trustworthy source: http://www.aviculture-europe.nl/nummers/14E06A03.pdf

 

[Skyeknight]

that drives speciation certainly, but isolation is the exception rather than the norm for life on earth, isn't it? E.g.
"hybridization between domesticated and wild populations is common in nature and thus could mislead the estimation of their genetic differences [32, 33]. Domesticated chickens have been affected by gene flow via hybridization with other RJFs and jungle fowl species over thousands of years [34, 35]." Wang et.al. Large-scale genomic analysis reveals the genetic cost of chicken domestication https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-021-01052-x

I completely agree with you! And I encourage gene flow. But a landrace is something like a group of domestic animals that have "thrived" in isolation in a specific environment. I don't care much for landraces and breeds also have a lot of problems. I myself collect a single individual from a breed and crossbreed them to watch how the mutations work etc. I feel like I am gatekeeping landraces and that is not my intention so apologies for that.

The scheme is nonsense. One example:
Schijndelaar is a new breed (around 2010) while Dutch is a very old one (recognised features around 1910 but in fact much older) . So Dutch cant be a descendant of Schijndelaar. The layer and broilers were bred after WWII.

I feel like you are misinterpreting the taxonomic tree. I know the Schijndelaar is the most recent developed Dutch breed. It is not saying the Dutch Bantam descended from it, it is saying that the Schijndelaar is closer related to a Welsumer than the Dutch Bantam is to a Welsumer. It's not about which were the ancestors of certain breeds, but which breeds share the most genetics with each other.

 

[Perris]

I you want to establish a group best fit for your garden and the way you feed them, you don’t need to bring in new genes

That isn't the aim, at least consciously. I started off with naïve notions about preserving rare breeds, but I soon realized that rare breeds have tiny gene pools, some are probably rare for good reason, and they are relatively fragile health wise. Then I realized that rare breeds are usually creations of one person, and the SOP got crystalized/ fossilized at one (relatively recent in the grand scheme of things) time. That was a bit of a watershed moment. What is the point of preserving that? A chicken is an animal not a museum object, living in the world not a cabinet.

So now what motivates me is the notion that a mix of breeds developed in different places at different times from different mixes is most likely to supply the most diverse range of chicken genes here and now, and that those best suited to the environment will thrive, and those least suited will die out. I already had evolved and cold-hardy (Swedish) when I added selected and heat-tolerant (Penedesenca), and all breeds have been chosen as good foragers and predator-aware by repute. The Fayoumis just added should bring proven disease-resistance as well as a relatively ancient pedigree. So I'm trying to bring a large and diverse range of genes into the same pool and letting nature sort and select them. I don't think it's the same as selecting for lots of eggs or a hefty carcass for the table, but maybe it is...?