Post by thrillbilly on Aug 6, 2006 12:07:37 GMT -5
Back about a decade ago I wrote this article for Gamecock and Feathered Warrior and it was then reprinted into Grit and Steel magazine.
Although I wrote this for gamefowl ie gamecocks and hens and offspring the same is applied to all chickens. I dug it out and thought that Id share it with some of you. Maybe it will help maybe it wont. But it may help explain some things you are seeing in your newly hatched fowl.
Warning. The logic and expertise in what follows is very much legit even though the writers lack of skill at putting it down on paper may not be the best lolol
Recurrent reciprocal selection:
Hens determine the sex of their offspring. In humans the chromosomes are labeled (x) and (y). In fowl geneticists labele them (z) and (w). the c*ck has two (zz) and the hen has one (z). Now if there is a (z) chromosome in the egg from the hen and there is ALWAYS a (z) chromosome from the sperm, then the offspring is a (zz) or stag. Whne the gg that comes forward has no sex chromosoome from the hen and a (z) from the sperm it is a pullet(zw).
This is uniquely different than humans. Remember the hen supplies no chromosome into the egg to produce a pullet. The cocks two (Zz) chromosomes are the same length. A chromosome is like a thin piece of string. The hen has two sex chromosomes also. Her (Z) is the same lenght as the cocks (Z) chromosome, BUT her (W) chromosome is so small, that it is considered by geneticists as non-existant and not present in the egg!!.
AGAIN one (z) from the c*ck and one (z) chromosome from the hen equals a stag. One (z) from the cocks sperm and one (w) condition, which is considered non-existant from the hen is a (zw) condition and equals a pullet.
The key here is that the pullet being formed in the egg, received much smaller genetic material than her brother,the stag, got from his father and mother!!. This is important because it gives rise to sex-linked traits. If you missed the point,re-read this over and over til you do!!
Now we see that the female in fowl, seems to be missing part of her genetic material. We MUST understand this to proceed to feather and leg colors. The hen will be involved by her sex-linked chromosomes to produice a stag or pullet. This state is directly linked to feather colors and leg colors.
Now before we continue,we must discuss dominant genes and recessive genes.You can go from dominant genes to recessive genes in fowl but NEVER from recessive to dominant!!
The combs; pea-combed , walnut,rose-combed, and straight comb are not sex-linked and will be discussed separatley later.
White legs are dominat over yellow,green and ble. Yellow legs are dominant over green and as seen above are recessive to white. Green legs are recessive to yellow and white. Grey genes for grey feathers are dominant to all other genes on chromosomes when present!!! Seems to be getting difficult to understand right?
WELL LETS CLEAR IT UP!!
Firt we will breed a grey hen to a red c*ck. When the hen supplies the (z) into the egg to form a stag she also supplies the chromosome into the egg for the color of grey feathers. the c*ck also supplies his chromosomes for his red feathers. What Happens!!?? The grey chromosome from the hen is dominant over the red chromosome from the c*ck; so every stag will be grey in color!! Now when the hen provides no sex chromosome into the egg for sex it is a (zw) for a pullet, she also DOES NOT put the chromosome for the grey color. It is absent!!. Now the c*ck puts in his red chromosome and being there is none from the hen all the pullets are 100 percent red.
Now this is so important to the cockers that have been around chickens for 20-60 years and believe that a red hen that is 1/2 grey will sooner or later throw a grey stag or pullet. SHE NEVER WILL!!! SHE CAN NOT!! WHY!! Because there are no grey chromosomes for the gray color in her body to begin with. It is absent!! The only color chromosome in her body is for the red color she has inherited from her father the c*ck.
What is wrong with our thinking is we think of this red hen as 1/2 red and 1/2 grey in all manners including grey color genes.
WRONG!!
As we just saw the grey color genes on the color chromosome is absent in the red pullets. Yes, she is half grey in her genes for gameness,cutting ability,flying,ringmanship,power,length
of her legs etc, but not for feather color or leg color. Feathers and leg colors are sex-linked to the sex chromosomes and may or may not be expresed in the offspring,depending on their sex.
Now you take this grey colored half grey and half hatch and throw it in a pen with red pullets. What will happen? This stag carries a dominant gene for grey feathers and a recessive gene from his father for red feathers. This stag is a hybred Het-er-ozy-gous individual.
Okay lets try this one. Stag(grey colored) 1/2 grey 1/2 hatch. Hen (red color) 1/2 grey 1/2 hatch. The red hen puts a RED gene into the egg for feather color when she applies the (z) chromosme for the stag offspring. the stag supplies a (z) always in the sperm. So (zz) equals stag. the feather color is chromosome is sex-linked. If the stag supplies the the grey dominant gene at the same time the hen supplied the red gene then the new stag will be GREY. Gray is dominant over red. Now when the hen supplies the red gene into into the egg as she supplies the (z) chromosome to make a stag and now the brood stag supplies the the recessive red color gen the offspring will be red. Remeber, this brood stag is a hybrid, crossed hatch/grey
He carries two color genes grey and red. Bred to a red hen you get half grey stags and half red stags. The pullets the same. you see now the red hen can and does throw grey stags when bred to a grey c*ck only. She does not have a grey gene for color in her body but the brood c*ck does and passes it 50% of the time to his offspring. Dont forget this is sex-linked. Every time a brood hen makes a stag in the egg she tries to contribute to that color of the stag. She may or may not be successful depending on whether or not her color is dominant or recessive to the brood cocks color genes. When she creates a pullet inn the egg by not supplying a sex chrmomsomein the egg she allows the cocks genes for color to determine the color of her offspring pullets.
A man wrote in The Gamecock that his red hens will dominate everything he breeds to them. That snows me. If he breeds a "pure" hom-ozy-gous peacombed white legged grey c*ck to his green legged ,red hatch hen that is stright combed every stag and pullet will be grey pea combed and white legged!! What did the hen dominate?
NOTHING!
And now for the rest fo the story. the c*ck and the hen determine 50/50 the gameness,cutting ability and fighting style of their offspring. When some breeders see a grey throw grey stags or a white legged hen throw white legged stags they immediately confuse sex linked traits with performance traits.
THEY ARE DIFFERENT!!
Never believe you can breed a dunghill c*ck to a game hen and get game stags. the genes for gameness are additive in nature. They combinme from both sides. If youve got lost, go back and rereadwhat we have covered so far.
Remember the key to keep in mind is that these colors for feathers and legs is sex linked.
Now lets try leg colors. My Madigan Clarets are dominant white legged. Lets breed him to a green legged hatch hen The stags will be white leggd because white is always dominant over green!! This is true for the pullets of this breeding as well. They are sex linked and white is dominant as well!!
Now if you thought that you bought pure clarets or whitehackles and making this cross for battle cocks you got yellow legs,complete blue legs,and green legs---guess what?
You been shafted by the seller. you have bought hybrid crosses.
In nature there are white legged fowl with blue splotches. Some claret and whitehackles with be born with tinted legs but this usually fades away. Breed a green legged hatch c*ck to white legged claret you will get 100% white legged stags and pullets will be blue and it doesnt fade and is permanent.
Now onto combs. My Leiper Hatch are 100 percent dominant peacombed from Red Richardson. Pure hom-ozy-gous peacombs are dominant over straight combs 100% of the time!
Breed your pure leiper to a straight combed claret hen and you will get 100% peacombed stags and pullets. Combs are not sex linked
Although I wrote this for gamefowl ie gamecocks and hens and offspring the same is applied to all chickens. I dug it out and thought that Id share it with some of you. Maybe it will help maybe it wont. But it may help explain some things you are seeing in your newly hatched fowl.
Warning. The logic and expertise in what follows is very much legit even though the writers lack of skill at putting it down on paper may not be the best lolol
Recurrent reciprocal selection:
Hens determine the sex of their offspring. In humans the chromosomes are labeled (x) and (y). In fowl geneticists labele them (z) and (w). the c*ck has two (zz) and the hen has one (z). Now if there is a (z) chromosome in the egg from the hen and there is ALWAYS a (z) chromosome from the sperm, then the offspring is a (zz) or stag. Whne the gg that comes forward has no sex chromosoome from the hen and a (z) from the sperm it is a pullet(zw).
This is uniquely different than humans. Remember the hen supplies no chromosome into the egg to produce a pullet. The cocks two (Zz) chromosomes are the same length. A chromosome is like a thin piece of string. The hen has two sex chromosomes also. Her (Z) is the same lenght as the cocks (Z) chromosome, BUT her (W) chromosome is so small, that it is considered by geneticists as non-existant and not present in the egg!!.
AGAIN one (z) from the c*ck and one (z) chromosome from the hen equals a stag. One (z) from the cocks sperm and one (w) condition, which is considered non-existant from the hen is a (zw) condition and equals a pullet.
The key here is that the pullet being formed in the egg, received much smaller genetic material than her brother,the stag, got from his father and mother!!. This is important because it gives rise to sex-linked traits. If you missed the point,re-read this over and over til you do!!
Now we see that the female in fowl, seems to be missing part of her genetic material. We MUST understand this to proceed to feather and leg colors. The hen will be involved by her sex-linked chromosomes to produice a stag or pullet. This state is directly linked to feather colors and leg colors.
Now before we continue,we must discuss dominant genes and recessive genes.You can go from dominant genes to recessive genes in fowl but NEVER from recessive to dominant!!
The combs; pea-combed , walnut,rose-combed, and straight comb are not sex-linked and will be discussed separatley later.
White legs are dominat over yellow,green and ble. Yellow legs are dominant over green and as seen above are recessive to white. Green legs are recessive to yellow and white. Grey genes for grey feathers are dominant to all other genes on chromosomes when present!!! Seems to be getting difficult to understand right?
WELL LETS CLEAR IT UP!!
Firt we will breed a grey hen to a red c*ck. When the hen supplies the (z) into the egg to form a stag she also supplies the chromosome into the egg for the color of grey feathers. the c*ck also supplies his chromosomes for his red feathers. What Happens!!?? The grey chromosome from the hen is dominant over the red chromosome from the c*ck; so every stag will be grey in color!! Now when the hen provides no sex chromosome into the egg for sex it is a (zw) for a pullet, she also DOES NOT put the chromosome for the grey color. It is absent!!. Now the c*ck puts in his red chromosome and being there is none from the hen all the pullets are 100 percent red.
Now this is so important to the cockers that have been around chickens for 20-60 years and believe that a red hen that is 1/2 grey will sooner or later throw a grey stag or pullet. SHE NEVER WILL!!! SHE CAN NOT!! WHY!! Because there are no grey chromosomes for the gray color in her body to begin with. It is absent!! The only color chromosome in her body is for the red color she has inherited from her father the c*ck.
What is wrong with our thinking is we think of this red hen as 1/2 red and 1/2 grey in all manners including grey color genes.
WRONG!!
As we just saw the grey color genes on the color chromosome is absent in the red pullets. Yes, she is half grey in her genes for gameness,cutting ability,flying,ringmanship,power,length
of her legs etc, but not for feather color or leg color. Feathers and leg colors are sex-linked to the sex chromosomes and may or may not be expresed in the offspring,depending on their sex.Now you take this grey colored half grey and half hatch and throw it in a pen with red pullets. What will happen? This stag carries a dominant gene for grey feathers and a recessive gene from his father for red feathers. This stag is a hybred Het-er-ozy-gous individual.
Okay lets try this one. Stag(grey colored) 1/2 grey 1/2 hatch. Hen (red color) 1/2 grey 1/2 hatch. The red hen puts a RED gene into the egg for feather color when she applies the (z) chromosme for the stag offspring. the stag supplies a (z) always in the sperm. So (zz) equals stag. the feather color is chromosome is sex-linked. If the stag supplies the the grey dominant gene at the same time the hen supplied the red gene then the new stag will be GREY. Gray is dominant over red. Now when the hen supplies the red gene into into the egg as she supplies the (z) chromosome to make a stag and now the brood stag supplies the the recessive red color gen the offspring will be red. Remeber, this brood stag is a hybrid, crossed hatch/grey
He carries two color genes grey and red. Bred to a red hen you get half grey stags and half red stags. The pullets the same. you see now the red hen can and does throw grey stags when bred to a grey c*ck only. She does not have a grey gene for color in her body but the brood c*ck does and passes it 50% of the time to his offspring. Dont forget this is sex-linked. Every time a brood hen makes a stag in the egg she tries to contribute to that color of the stag. She may or may not be successful depending on whether or not her color is dominant or recessive to the brood cocks color genes. When she creates a pullet inn the egg by not supplying a sex chrmomsomein the egg she allows the cocks genes for color to determine the color of her offspring pullets.
A man wrote in The Gamecock that his red hens will dominate everything he breeds to them. That snows me. If he breeds a "pure" hom-ozy-gous peacombed white legged grey c*ck to his green legged ,red hatch hen that is stright combed every stag and pullet will be grey pea combed and white legged!! What did the hen dominate?
NOTHING!
And now for the rest fo the story. the c*ck and the hen determine 50/50 the gameness,cutting ability and fighting style of their offspring. When some breeders see a grey throw grey stags or a white legged hen throw white legged stags they immediately confuse sex linked traits with performance traits.
THEY ARE DIFFERENT!!
Never believe you can breed a dunghill c*ck to a game hen and get game stags. the genes for gameness are additive in nature. They combinme from both sides. If youve got lost, go back and rereadwhat we have covered so far.
Remember the key to keep in mind is that these colors for feathers and legs is sex linked.
Now lets try leg colors. My Madigan Clarets are dominant white legged. Lets breed him to a green legged hatch hen The stags will be white leggd because white is always dominant over green!! This is true for the pullets of this breeding as well. They are sex linked and white is dominant as well!!
Now if you thought that you bought pure clarets or whitehackles and making this cross for battle cocks you got yellow legs,complete blue legs,and green legs---guess what?
You been shafted by the seller. you have bought hybrid crosses.
In nature there are white legged fowl with blue splotches. Some claret and whitehackles with be born with tinted legs but this usually fades away. Breed a green legged hatch c*ck to white legged claret you will get 100% white legged stags and pullets will be blue and it doesnt fade and is permanent.
Now onto combs. My Leiper Hatch are 100 percent dominant peacombed from Red Richardson. Pure hom-ozy-gous peacombs are dominant over straight combs 100% of the time!
Breed your pure leiper to a straight combed claret hen and you will get 100% peacombed stags and pullets. Combs are not sex linked