This post of mine is prompted by discussions I have had in the past with poultry breeders, comments by Smyth and by Robbpa's suggestion to read the article on The Chook Shed about breeding Gold Pencil Hamburg (http://www.webone.com.au/~greggles/gp2.html).

First of all, the "pencilling" is really autosomal barring. (First of all before that, Greggles claims copyright on that site (The Chook Shed) and I don't believe he is the owner of the copyright for all the illustrations there...but, this is another matter... The University of Illinois publishes a professional journal titled "Journal of Law, Technology & Policy" (http://www.jltp.uiuc.edu) which addresses a lot of legal issues on the internet. The day will rapidly arrive when people infringing on copyright laws on the internet will be held accountable. (If you want to refer to something, don't copy it and reproduce it on another site, just make a link to it... that's completely legal.))

Back to 'gold pencil hamburgs' ... The 'pencilling' of "gold pencil hamburgs" is due to autosomal barring. Here I quote Smyth in R.D. Crawford, Editor, "Poultry Breeding and Genetics", Elsevier, Chapter 5, page 129: "The terminology associated with the pencilling and autosomal barring patterns has been CONFUSED by the exhibition poultry breeders' referral to BOTH phenotypes as pencilling. One is characterized by concentric rings wholly contained within the feather, while the other is the parallel type referred to by geneticists as autosomal barring. Therefore, Silver Pencilled and Partridge Plymouth Rock females have concentric-pencilled feathers, while their male counterparts are wild-type. In contrast, Silver Pencilled Hamburg females are autosomal barred and the males are Columbian-like with black restricted to the wings and tail."

This issue (pencilling being confused with autosomal barring) is different from our issue of pencilling being confused with lacing....

so,lacing as defined above. pencilling is used to define a type of barring,it is lacing whether fine or coarse, single or double. i think the hamburg club has discovered the fault of using pencilling in their standard. i hope i can find a way to get that book as my local library has been been a month trying to get me a copy on loan.

Well... pencilling is used to describe more than autosomal barring... Sometimes "Pencilling" describes the black lines on a roosters (white) hackles....

The pattern gene (Pg) probably came into Europe and America with the the Chinese Cochins, or Brahma or both, since they look like they are related. I've speculated, with a large grain of salt, that the old time breeders knew what they were talking about when they called them both penciled. Pg and Ml are linked by 10 cM (only 10% recombination). When they crossed a partridge penciled bird to their Db Hamburgs (Spangled Hamburgs) they would segregate both gold and silver autosomal barred progeny. The F1 itself would be autosomal barred. The linkage would have been Db pg+ Ml (Hamburg) and db+ Pg ml+ (Cochin descendant) They might have kept the penciled designation because they knew that the same factor was responsible for both patterns, but in the different genetic backgrounds.

Db is linked to Pg by 23 cM and the Db Ml linkage is 33 cM (Db 23 Pg 10 Ml), so the most likely recombinant chromosome to produce from the hybrids is the new Db Pg autosomal barred linkage. Not only that, but since the interaction between Db and Pg is dominant they could have kept selecting the barred birds until they got the recombinants, and got a very good pattern.

you know roc, you are not too far over my head, i am just yoo far under yours. i want to know whats right on this, but the bottom line is, it is the common usage in the fancy that counts most to me. you know what impresses me is how dedication and attention to detail has allowed so many undereducated people to elevate the type of stock they keep merely by the eye of the beholder. it has worked well for me in the past,i think i want to know the why of it. i am catching some of the whys at this site. too bad i could npt have become this addicted in school .darn homemade wine makes me talk too much.

Hamburgs have the gene Db that is needed to create the autosomal barred pattern if you also have Pg. Partridge birds have the Pg, but they do not have Db so they have the concentric laced pattern. Both genes are dominant (they are expressed in the hybrid), so when you cross a Spangled Hamburg to a partridge pattern bird you get a poorly autosomal barred bird. Spangled Hamburgs also have the gene called Ml, but as one copy without another gene called columbian (Co) you still see the autosomal pattern. You now have three dominant genes in the hybrid the Hamburg donated Db pg+ Ml and the partridge bird donated db+ Pg ml+ so the hybrids are Dbdb+ Pgpg+ Mlml+ triple heterozygotes (two different alleles at the same gene location). There is linkage because all three genes are on the same chromosome, but let's forget about that. You can now form all the the laced patterns except single laced by breeding the hybrids together.

You can get autosomal barred DbDb PgPg ml+ml+, partridge db+db+ PgPg ml+ml+, double laced like Barnvelders db+db+ PgPg MlMl. You can also get DbDb PgPg MlMl, but there is no feather pattern like this in the fancy so I don't know what it looks like. It must look pretty ugly or someone would be breeding the color. If you add columbian to the Barnvelder type you get CoCo db+db+ PgPg MlMl and this is the single laced color type. All of these patterns seem to show up best if the birds are ebeb (brown at the E locus).

If you have CoCo DbDb PgPg MlMl and birchin ERER at the E locus you will get the laced tailed single laced type that you see in Sebrights and Laced Polish.

This is just the genetic explanation for the laced and penciled patterns.

thankyou,I will make a copy and study. I WILL grasp this sooner or later. I do have a personal question, if you wish. What is your motivation to give so much of your time and knowledge to this site?

info do you mean to say, pencilling is used to describe tttttttttthe bblack lines on a white or other color hackle , that is NOT lacing. that lacing and pencilling are not interchangeable terms by definition.

Thank you Robb and Rokimoto. I see two issues here. #1) Robb, as you said, one issue is the meaning of "pencilling" as used in the fancy, and #2) the genetic definition of pencilling as stated by Smyth, for example ... and it seems to me that the two useages of the term 'pencilling' are not the same.

At some point, one must accept an 'authority' (like the dictionary if one is talking about the meaning of words, or the encyclopedia...). I take the information in Crawford's volume to be the authoritative reference, and I believe the scholars who wrote the chapters were very careful and strived to be correct. A lot of what Rokimoto writes is in Smyth's Table 5.3 in Chapter 5 of Crawford. Smyth insists on referring to the Hamburg type of 'barring' as autosomal barring ('autosomal' to distinguish it from sex-linked barring) rather than pencilling. Smyth lists three types of autosomal barring (that fanciers sometimes call 'pencilling'): the Hamburg, Fayoumi and Buttercup types. Genetically they have different alleles at the E-locus and the Fayoumi type has Co in addition.

Regarding the black lines on the white rooster hackle, I meant to say that there are cases in which the term 'pencilling' is clear and makes sense, such as the black 'pencil lines' in the white hackle ... I agree, that isn't lacing at all. But, there are 'pencilled' birds that look like they're laced (please see the Wyandottes on Feathersite)! That's where the confusing comes in for me.

Rokimoto, I have read about single gene for autosomal barring.... I was trying to find that reference this morning but don't put my hands on it quickly. Is this a known gene?

Robbpa:

I contribute to this site because it is recreational. I just completed a grant budget and switched over to the web. Budgets and grants are the worst thing about science. I learn a few things and I help a few people out. I remember when I was starting out and I wanted to know this stuff, but I couldn't get my hands on the any of the knowledge. Even when I was in college I went to research institutions that didn't have agriculturally related journals so I had to make do with biological abstracts and try and figure out what they were doing from their results. There are also people like Don Frame who gave me my first set of show quality bantam eggs, and all the people in the feather club that told me what they were doing. When I was a member of the Salt Lake Club it was a very cooperative group. I heard stories that it wasn't always like that, but it was when I was there. I think that you have to get lucky and find the right people to help you out. Your local Fancy club would probably be the place to start, and you'll probably meet some new friends. They are competitors, but most of it is on a friendly basis, and any club that will not help beginners is going to go extinct. I think that they all realize that and promote aid whenever they can.

Infomaniac:

Before Carefoot's work autosomal barring was thought to be an autosomal recessive gene (ab). Hutt based his conclusions on the Campine crosses. Campines probably have ER (birchin) and the autosomal barring doesn't show up on the mostly black bodied F1 hybrids so they thought it was recessive. It would have been different if they had crossed Hamburgs to partridge or Dark Brown Leghorn type birds with the eb (brown or partridge) allele. If they had done the eb cross they would have classified it as Ab and dominant, but they would have still been wrong. We know now that autosomal barring is due to Db and Pg interacting together. When birchin is present like in the Fayoumi (maybe in the Campines, but I don't think that it has been verified) you need Co to get the autosomal barring pattern. As far as I know there is no other autosomal barring gene. If you can find Hutt 1946 Genetics of the Fowl, I think he has a section on ab.

If I had had this much access to genetic info when I was a teen, I would have exploded! I had science teachers who were full of misconceptions about genetics (then called heredity) and who were completely unable to guide me. Thanks to all of you who share your knowledge :-)