There are two white genes in American Bresse Chickens: Dominant White and recessive White. Here are the reasons why French Bresse breeders have chosen to keep Dominant White Bresse genes, and not Recessive White genes.
When white American Bresse chickens were imported from France, each one arrived with double copies of Dominant White genes which produce solid white plumage. The recessive white gene also came from France, but it did not come in white Bresse birds; it came hiding recessively in the color varieties of Bresse - Black, Blue, and Splash.
Let's talk about these two types of white genes! A big THANK YOU to Nancy Norwood for the article below, which helps to clarify differences between the two white genes, and provides reasons for best breeding practices and choices.
Let’s take a look at those recessive white and dominant white genes in American Bresse.
Neither gene is completely dominant over the other, and unfortunately we currently have both of these genes represented in the American Bresse gene pool.
Because these genes function differently, I thought it might be helpful to actually look at some photos and talk about how we can identify both.
Two copies of recessive white in a COLORED flock results in a dusty yellow chick that matures into a snow white bird. It requires two copies of recessive white to result in a recessive white bird. (Pictured below.)
So, if you breed a black to a black and both carry white recessively, then you have a good chance of getting a recessive white chick. The same can happen with a blue x blue. If they both carry recessive white you can get a recessive white chick.
Two copies of recessive white in an otherwise DOMINANT WHITE flock results in...
Why is this important?
Because if you put that recessive white chick into your white flock with all of your other dominant white birds, you will begin to hatch chicks that are an ugly mess genetically, and you won’t know which bird the mess came from. Don't forget that dominant white birds are also masking a color.
Your first clue will probably be a few yellow chicks in the brooder with black spots. Who knew that white birds bred to white birds could result in spotted or even colored chicks? It's all there in the genetic instructions.
If I paint two coats of white paint over a black barn, I will have a white barn. It will take both coats to do a good job of it and turn the black barn well and truly white.
What happens if I paint only one coat of paint? Will some black streaks show through? You bet they will. That’s a picture of how dominant white works. The black or blue (or other colors) are always underneath.
A dominant white bird needs two genes for dominant white. If a bird only gets one gene for dominant white, then its base color “leaks” through.
Remember when I said that recessive white in your dominant white pen is a problem? What if you have dominant white (98% of Bresse) with recessive white carried in their gene pool?
You will inevitably end up with a genetic mess.
One copy of dominant white and one copy of recessive white produces a white bird with lots of color leakage. It's like every underlying color can leak through. It’s like an old house with multiple layers of paint that have been scraped off in a few places. Anything that is in the bird's genetics can leak through.
Because mixing dominant and recessive white genes in the same flock is sure to result in incorrectly colored chickens, you can avoid the entire genetic headache by NOT mixing the two white genes in American Bresse flocks.
Genes do things. They have consequences. Using recessive white genes in American Bresse flocks may affect the breed as a whole. But first, it will affect individual flocks, and I'm not sure whether it will be for better or for worse.
Given the fact that the White American Bresse breed as a whole is made up of mainly Dominant White birds, here are SIX known consequences to injecting recessive white genetics into a dominant white American Bresse flock.
Use of dominant white genes was the chosen path of the original French breeders for the last five hundred years, for at least the above reasons. They minimized fraud and gene dilution through legal protections, maintained bird size within their desired parameters, and now they control the extent of yellowing via selective breeding.
The singular drawback to the dominant white gene in the minds of some breeders is the propensity to yellowing. Because it is dominant to black but incompletely dominant to yellow pigment, dominant white can allow for some leakage of yellow pigment into the plumage, especially in roosters, in some cases more so than others.
The ability to completely eliminate yellowing sounds like a brilliant idea to some breeders. But, let's finish thinking this through!
After five hundred years, the French STILL keep their dominant white flocks and their legal protections. It ain't broke and they're not trying to fix anything. Yes, in France one can still see tinges of yellowing in Bresse roosters. Yellowing can be minimized over several breeding seasons through using solid black (not silver) as a base color, and then selectively breeding the birds with the least yellowing.
Don't forget that dominant white birds are up to 1.5 pounds heavier than recessive white pasture-mates. If that means a slightly higher income potential, I'm happy to keep the dominant white genes with the yellowing and accept the challenge of selectively breeding toward whiter plumage.
Recessive white genes came to North America in colored Bresse imported from France. They were then mistakenly introduced into our dominant white stock. Now we are already seeing these recessive white genes popping up more and more in our dominant white flocks. The mixed dominant and recessive birds that show the obvious black leakage lets the breeder know that the recessive gene has entered the flock. Any chicks that are 100% recessive white will likely fly under the radar for awhile, making your job of finding them all very difficult.
Recessive white should be selected away from, most especially in the dominant white flock, but also in colored flocks as well.
Here are some clues to look for. If the job of identification proves too difficult, I recommend either starting over with dominant white stock from a reputable breeder, or implementing genetic testing so you can cut to the chase and begin hatching 100% dominant white chicks with no black spots.
In color flocks, the recessive white chicks will stick out like a sore thumb. They are those few dusty white chicks amongst the full color ones. Those chicks are homozygous recessive white (two matching genes). They are easy to identify. If you breed two colored birds together and get a white chick, it must be a recessive white. These chicks will grow into snowy white adults. (The gray sheen goes away entirely.) You can’t always tell them apart once they grow into their adult plumage.
The presence of recessive white chicks means that BOTH the rooster and the hen are recessive white carriers. (If you haven't pair-hatched, you'll need to determine which birds are the parents.)
DON'T SELL your recessive white chicks as breeders! They ARE delicious and the white feathers pluck cleanly. But if your freezer is already full, sell them as egg-layers to families and homesteads. Do the right thing and ensure that your customer knows the genetics are incorrect, and therefore they are not for resale, but only for family use.
DON’T buy a recessive white bird and put it in your dominant white flock! Ask the breeder before buying. Are you getting recessive whites in your black/blue/splash flock? Don't put them in with the dominant white flock! Please recognize that Recessive White birds and Dominant White birds are two completely different fowl, and very poorly compatible (Hutt, 175), despite the fact that they look very similar.
In the photo at the top of the page you can see the leakage I was talking about. The young cockerel is possibly a pure American Bresse but because of the existence of the two conflicting genes, the "paint" is leaking both black and gray/cream.
IDENTIFY carriers of the Recessive White gene and any Recessive White birds. This is difficult, since both the dominant and the recessive white usually look virtually identical in adult birds. In time, you may be able to pick up on the clues that are specific to your particular flock:
Could Beak Color Help Identify the Recessive White Bird in Your Dominant White Flock? An interesting observation by Camren Cambra is that the 100% recessive white birds (not the dominant/recessive mix) tend to have white beaks. This would also be a fantastic way to identify them if you have any in your adult dominant white flocks.
If these recessive white genes in American Bresse can be identified and pulled out, you can stop getting the accidental spotted chicks and leakage adults! I know I have a recessive white hen in my dominant white pen because she has produced the boy in the top photo. I know her egg color and I don’t hatch them, but finding her is a huge problem, so I’m excited to look for her!
I hope these tips help you to sort your birds and hatch less leakage!!
Despite her decades of chicken-breeding experience, Nancy Norwood prefers not to use the fancy nomenclature of geneticists. Instead, she talks genetics in a way that most everyone can understand. "I didn't learn with official terminology," she says. "I learned by doing. My education might be old school, but having even a basic grasp of genetics can help our flocks improve."
Research, edits, and formatting by Karen Patry, Ambresse.com
References for White Genes in American Bresse:
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