This Rooster Ilustrates Why It's Difficult to Judge Mixes

[speckledhen]

No clue but what a pretty boy <3

Thanks, he was a good boy. Loved his blue shade. He was large fowl Buff Orp rooster x bantam blue frizzle Cochin x Silkie (and maybe something else), but he looked enough like a blue Ameraucana to the untrained eye for someone to steal his photo to sell them, LOL.

I like the crazy mixes we've accidentally ended up with over the years like my Poufy Head sisters. Mothers were pure BRs, sire was a red colored mixed Silkie/Cochin and whatever else was in there. He had feathered legs and the pouf. They were three different sizes, laid eggs with size corresponding to their body size. No feathered legs. Here was one. Great little hens.

 

[JedJackson]

This thread is interesting! I think most of all it illustrates that there is a lot we still don't know about genetics, but more than that there are a lot of hidden genes in our purebreds waiting for the right combinations to pop out. A great example of that are Auburn Javas that reappeared from Black Javas some years back during an intensive breeding project of the latter variety. And even our established breeds have different strains that can and often do have different ancestry from one another, and crossing these different strains can result in all kinds of genetic weirdness.

Having said all that, I still think ancestry of mixes can be determined with a certain amount of accuracy in many cases, especially if the parents were purebred.

 

[speckledhen]

This thread is interesting! I think most of all it illustrates that there is a lot we still don't know about genetics, but more than that there are a lot of hidden genes in our purebreds waiting for the right combinations to pop out. A great example of that are Auburn Javas that reappeared from Black Javas some years back during an intensive breeding project of the latter variety. And even our established breeds have different strains that can and often do have different ancestry from one another, and crossing these different strains can result in all kinds of genetic weirdness.

Having said all that, I still think ancestry of mixes can be determined with a certain amount of accuracy in many cases, especially if the parents were purebred.

I do love that term "genetic weirdness", mainly because I've seen so much of it, including the dwarf gene in my Delaware line. That is one other gene that folks believe happens a certain way and is passed a certain way, but years ago, before I was aware that my rooster was a carrier, my best friend hatched some eggs from me, giving her two hens, one very large and chunky and one smaller bodied. Then, someone hatched a dwarf chick from eggs I sent to them and I began to research the trait. This is thyrogenous dwarfism, that is semi-lethal. Chicks only show it around 3 weeks of age when you notice curved, short parrot-like beaks, mongoloidish looking eyes, a too-round head, usually curved outer toes and of course shortened legs that stop growing at a certain point.
Anyway, her vet at the time in Oregon was, coincidentally(and wonderfully), doing research on dwarfism in poultry and asked if he could test those two hens. The smaller bodied hen carried no dwarf gene. This is where it gets weird and out-of-textbook. The larger hen carried TWO copies of the gene! He said his colleagues did not believe it could be true, but there were the test findings. He said not to reproduce her because, even if the sire carried no dwarf gene, she could produce dwarfs by herself, giving two genes to the chicks without a contributor on the other side. I cannot remember his name, but I believe he was publishing a paper on it, would have to ask Ladyhawk.
Our experience with the dwarf gene goes to show, once again, that genes are not as understood as we think sometimes.

 

[JedJackson]

I do love that term "genetic weirdness", mainly because I've seen so much of it, including the dwarf gene in my Delaware line. That is one other gene that folks believe happens a certain way and is passed a certain way, but years ago, before I was aware that my rooster was a carrier, my best friend hatched some eggs from me, giving her two hens, one very large and chunky and one smaller bodied. Then, someone hatched a dwarf chick from eggs I sent to them and I began to research the trait. This is thyrogenous dwarfism, that is semi-lethal. Chicks only show it around 3 weeks of age when you notice curved, short parrot-like beaks, mongoloidish looking eyes, a too-round head, usually curved outer toes and of course shortened legs that stop growing at a certain point.
Anyway, her vet at the time in Oregon was, coincidentally(and wonderfully), doing research on dwarfism in poultry and asked if he could test those two hens. The smaller bodied hen carried no dwarf gene. This is where it gets weird and out-of-textbook. The larger hen carried TWO copies of the gene! He said his colleagues did not believe it could be true, but there were the test findings. He said not to reproduce her because, even if the sire carried no dwarf gene, she could produce dwarfs by herself, giving two genes to the chicks without a contributor on the other side. I cannot remember his name, but I believe he was publishing a paper on it, would have to ask Ladyhawk.
Our experience with the dwarf gene goes to show, once again, that genes are not as understood as we think sometimes.

Wow, that is strange! You'd expect the smaller hen to carry any dwarf gene and you'd never expect the large hen to carry two copies. How is that even possible? But chickens, having been bred for centuries to suit human needs, must be constantly evolving. I don't have a strong grasp of the science of genetics, but I would guess constant and rapid evolution would do strange things and cause mutations and other genetic anomalies to occur more than would be the case with a wild bird like the jungle fowl. There's also the intriguing mystery of just which species contributed genetically to chickens, and how much. At one time scientists believed they were strictly descended from red jungle fowl but they are finding more and more evidence that gray and green jungle fowl were a little involved in the mix too.

 

[speckledhen]

Wow, that is strange! You'd expect the smaller hen to carry any dwarf gene and you'd never expect the large hen to carry two copies. How is that even possible? But chickens, having been bred for centuries to suit human needs, must be constantly evolving. I don't have a strong grasp of the science of genetics, but I would guess constant and rapid evolution would do strange things and cause mutations and other genetic anomalies to occur more than would be the case with a wild bird like the jungle fowl. There's also the intriguing mystery of just which species contributed genetically to chickens, and how much. At one time scientists believed they were strictly descended from red jungle fowl but they are finding more and more evidence that gray and green jungle fowl were a little involved in the mix too.

That was exactly our reaction when he told my friend the findings of the blood tests. And my rooster was a big boy, too, but since his grandson and one of his granddaughters are gene carriers, as we discovered over the past year, he had to be. The hens involved came from an old fine heritage line of Barred Plymouth Rocks and I've never heard one peep about any dwarf gene in them from anyone, anywhere, so it came from the Delaware line.

Normally, it takes one gene from each parent to produce a dwarf. And each parent contributes the gene to roughly half of its progeny. So, it's like dwarf roulette where you must have two balls fall in one slot to produce a dwarf. If only one gene is passed from one parent to the chick, the chick is a carrier, but shows no sign of it until bred with another carrier and they both contribute a gene to produce a dwarf. So, you can see how you can breed for literally years and not know you have dwarf gene carriers. But, in the case of the big Delaware hen, the tested two-gene carrier, if we had gotten a dwarf chick, we'd be thinking the sire of the chick was a carrier when it was all her. Luckily, her eggs were never hatched.

By the way, if you've never seen a dwarf chick, I had two this past year, Barred Rocks descended from my Dellie rooster (grand-chicks of my 1/4 Del rooster) and I have YouTube videos featuring them, called Piglet and Pooh-bear. I knew they would not live long so they didn't get big names. This type of dwarf never makes it to sexual maturity, though Pooh lived to about 14 weeks old.
Pooh died not long after I made this video:

 

[JedJackson]

That was exactly our reaction when he told my friend the findings of the blood tests. And my rooster was a big boy, too, but since his grandson and one of his granddaughters are gene carriers, as we discovered over the past year, he had to be. The hens involved came from an old fine heritage line of Barred Plymouth Rocks and I've never heard one peep about any dwarf gene in them from anyone, anywhere, so it came from the Delaware line.

Normally, it takes one gene from each parent to produce a dwarf. And each parent contributes the gene to roughly half of its progeny. So, it's like dwarf roulette where you must have two balls fall in one slot to produce a dwarf. If only one gene is passed from one parent to the chick, the chick is a carrier, but shows no sign of it until bred with another carrier and they both contribute a gene to produce a dwarf. So, you can see how you can breed for literally years and not know you have dwarf gene carriers. But, in the case of the big Delaware hen, the tested two-gene carrier, if we had gotten a dwarf chick, we'd be thinking the sire of the chick was a carrier when it was all her. Luckily, her eggs were never hatched.

By the way, if you've never seen a dwarf chick, I had two this past year, Barred Rocks descended from my Dellie rooster (grand-chicks of my 1/4 Del rooster) and I have YouTube videos featuring them, called Piglet and Pooh-bear. I knew they would not live long so they didn't get big names. This type of dwarf never makes it to sexual maturity, though Pooh lived to about 14 weeks old.
Pooh died not long after I made this video:

So it's basically a lethal gene like the one for tufts in Araucanas and the short leg gene in Japanese bantams? Recessive until two copies appear. But what puzzles me is how the large Delaware hen with two copies didn't show any symptoms-- that is very strange. So maybe it's a little different from lethal genes after all.

It's very interesting stuff. You never know what may be lurking in the gene pool. But at least you became aware of what was going on and were hopefully able to come to some positive outcomes as a result.

 

[speckledhen]

No, it's a semi-lethal gene. The chicks can live quite awhile, they don't die in shell like with a lethal gene. The Araucana and Japanese genes are definitely lethal genes.
What is bad about the dwarf gene is the waste. They will never lay an egg, will never produce a chick. You watch them seem perfectly healthy and robust and suddenly, they live for weeks and weeks and then, they die almost overnight. That is this type of dwarfism. There are other types that allow the bird to live much longer and achieve sexual maturity. Basically, they are just short, more than anything else. Thyrogenous dwarfism is not fun at all. I have an article on BYC about it with photos.

As far as showing symptoms, a basic dwarf gene carrier will show none. I still have two hens that I believe carry it. I know one does and could be both do. I cannot breed from them with their sire, period, since he also carries. If I put them in another pen, they will just introduce the gene into that line as well, though it currently has nothing of the kind. But, the problem is that you do not know any bird is a carrier until it meets up with another carrier, produces chicks and eventually, a dwarf. Why the hen with two copies was not a dwarf herself and showed no signs of it, I cannot tell you. Another genetic mystery.

I guess we've sort of veered off the path we started on, my point that with a cross, you often just cannot say what is in the mix. Even if you think you have two pure breeds, what if one of those carries some genetic material way back in its lineage and that happens to show up in the chick? That really muddies the waters.

 

[21hens-incharge]

I have been reading and finding it fascinating.

off topic or not it is educational.

 

[speckledhen]

I have been reading and finding it fascinating.

off topic or not it is educational.

Glad we aren't boring you! Hopefully, others will also get something from the discussion, though we've veered more into genetics and heredity than "what is my chicken?" now.

 

[speckledhen]

I'll give you an easier one to make up for C.J., okay? This one I created myself here so I'm 100% positive of who the parents were, only two breeds involved in this cross so you'll get it. The blue one and the black one are full brother and sister. Easy-peasy on this one, no mysteries here, I bet. I loved this cross and really miss the parents involved. By the way, the big guy in the group is the same exact age as the rest in that first photo! I called him the draft horse of chicks and it fit. His owner named him Sherman, as in Sherman tank.