Chicken Genetics

[Arielle]

Quote: Great details Karen. Now I know why you are emphatic about this coloring. I need to go pound nails and mull this over.

 

[Arielle]

BBR is regarded as the most basic color. Because it is a bird, more genes are in effect than just the red Some thing allows the black breast to show in the phenotype and something effects the wing color separating it from the Black copper marans.

Maybe they are all homozygous. And either recessive or dominant. But the loci for the other genes that effect color must have an allele.

 

[3riverschick]

BBR is regarded as the most basic color. Because it is a bird, more genes are in effect than just the red Some thing allows the black breast to show in the phenotype and something effects the wing color separating it from the Black copper marans.

Maybe they are all homozygous. And either recessive or dominant. But the loci for the other genes that effect color must have an allele.

The BBR is a completely recessive color palette. There are no hypostatic genes in BBR. Every other color gene other than s+ or s- corrupts BBR and BBR disappears to one extent or another. The wonderful thing about BBR is...if one can get it in its pure-breeding state... it just self-replicates. No color balancing , no worries about winnowing or adding other genes. BBR is already completely winnowed for color. It's why it fascinates me. The thought of a self-replicating color so I could just spend my time breeding to type instead. Ah, what a genetic luxury! ( and such pretty chicks too!)
Best,
Karen

 

[Arielle]

Quote: THanks for confirming. I am learning!!

 

[Arielle]

http://chickengenetics.edelras.nl/

http://kippenjungle.nl/Overzicht.htm#kipcalculator



I have been using BOTH of these to better understand.

I keep running into those who say, and I'm paraphrasing, that Mendelian genetics don't apply to chickens. What am I not understanding. I thought Mendel was the founder of genetic and selection as we know it today. He provided the foundation, and today the chicken is another mapped genome and selection as reached a point of additive and non-additive genes that the poultry industry was divided into meat production and egg production. ( The KWPN divided it's horses into jumpers and dressage breeding directions a few years ago when research revealed the jumping genes work against the dressage genes. Sounds a bit like meat and eggs in chickens to me).

 

[3riverschick]

Hi Arielle,
Try this: http://bellwethercollies.webs.com/breedingplans.htm . It is the genetic history behind our collie kennel and the stunning 10 puppy triple-hybrid strain-cross litter which was so like peas in a pod.
Basically what Darwin is saying is to find a female who is a double hybrid. This female must have 75% of her blood pure in each strain her sire and dam lines represent. Then cross her with a stud who is closely linebred (or even better, bred pure-in-the-strain) of a completely unrelated line. Done this way, the get from such a union will resemble their sire as closely as if they were hatchling/litter siblings.
However, if one reverses the sexes and mates a closely linebred female to a double hybrid male, the get will not resemble either parent.
So, I think if one were seeking to establish biodiversity in a flock, the former way would be the way to do it and not lose type. The key would be in the chosen lines of the dam and their 75% ratio of purity plus the selection of a closely linebred cock of superlative merit from a third line.
Darwin also states that genetic merit in the abstract is a very valuable (actually, essential) tool in such matings. This is where study of the lines involved and ability to balance excellence in the abstract is a vital skill. I used written charts of percentage of characteristics ( pics can lie) to balance my breeding animals in the abstract.
Best,
Karen

 

[Arielle]

Karen: This was an interesting read. I've had a very good rottie, she and all her litter mates closely resemble the father. IT was like looking at clones by the time they were 6 months old. THe breeder had a very good b--itch and was quite large at 100#. All the pups finished about 80#, noticably smaller like the father.

THe collie get become a three breed hybrid. I'm thinking the 3 breed rotational system is a compromise. To make the triple hybrid there must be three linebred or inbred lines to work with. Long term, perhaps there is a place for all the methods and each has it's value at given points in continuing or developing productive lines. Make sense?

 

[3riverschick]

Karen: This was an interesting read. I've had a very good rottie, she and all her litter mates closely resemble the father. IT was like looking at clones by the time they were 6 months old. THe breeder had a very good b--itch and was quite large at 100#. All the pups finished about 80#, noticably smaller like the father.

THe collie get become a three breed hybrid. I'm thinking the 3 breed rotational system is a compromise. To make the triple hybrid there must be three linebred or inbred lines to work with. Long term, perhaps there is a place for all the methods and each has it's value at given points in continuing or developing productive lines. Make sense?

Yes, I did study 3 breed rotational crosses and adapted the system to strain-crossing instead of breed crossing. Yes, finding the three veteran linebred strains was difficult. It took me 2 years to find them , vet them for health, and cross balance all three lines for Health Type and Temperament in order of their excellence from greater to a lesser extent.
Strain A: Health Temperment Type ( My foundation girl)
Strain B: Type Health Temperment ( Sire of A/B litter)
Strain C: Temperment Type Health( Sire of A/B/C litter)
It reads like this: In Strain A; the 1st reason I went to it was Health, the 2nd reason was Temperament and the 3rd reason was Type. etc. etc. What we end up with is excellent balance in the abstract. I just love the research and the challenge. At one point I even spent 8 months after the A/B litter was born extrapolating the kennel breeding program out to 13 generations. Including a huge master pedigree I still have upstairs. What you wrote makes perfect sense to me.
Best,
Karen

 

[Arielle]

A master breeder recommended the 3 breed rotational system. It maybe more suitable for some breeds than others.

 

[Henk69]

A few remarks:

BBR is not a super name for the wildtype color. Because they are genetically GOLD, not always red enhanced which I would call RED like in Rhode Island Reds. Also wheaten, duckwing and brown males are the same male color, and it doesn't point to the difference with the crow winged colors that are black breasted and show "red" too. In fact all e-locus variants (wheaten,duckwing,brown,birchen,extended black) have black breasted male color.

GOLDEN is not a super name either, because it is often used as the description for heterozygous silver/gold which would be more or less brassy looking silver in appearance. I know that gold means the same as golden, but still ...

So the wildtype chicken should be called GOLD DUCKWING. We tend to do that at the-coop.org
Duckwing is a stupid name too, but at least it points to the right area of the wing that is typical.

There is no such thing as s-
Suggested notation:
s+//s+ (or s+/s+) for males,
s+/- for females.
s+/(s+) for both genders.
A slash represents a chromosome, in females the piece of chromosome where the second gene would reside is missing, hence only double slashes for the male here, which is mostly simplified as a single slash anyway.