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#116214 - 12/01/16 05:16 PM Re: MGB e+/e+ X eb/eb silver pencilled dotte [Re: Wieslaw]
KazJaps Offline
Classroom Professor

Registered: 08/30/02
Posts: 2799
Loc: Australia
Originally Posted By: Wieslaw
Originally Posted By: Hebe
The UK Partridge Wyandotte club have http://www.partridgewyandotteclub.co.uk/Genetics.html some interesting pics:


Those pictures confirm the old(from 1800s) saying, that the cocks from pullet lines will have leakages, and the hens from cockerel lines are without Pg.


Not really. I would say the opposite, considering there are clean black breasted roosters where their hens have Pg concentric pencilling. Ie, the actual Pg gene does not put phaeomelanin markings on the eb roosters. That's why Smyth et al. had to use juvenile plumage (pseudo transverse barring) to identify Pg in cockerels, ie couldn't identify Pg in adult males.

In old poultry books I've read, it was the British Wyandotte breeders that started the double-mating (very good records on Silver-laced), & this caused some problems with the mixing of lines from different countries. The USA & UK Partridge Wyandottes have different Standards (USA red enhanced, UK gold diluted) & Australia now has the USA Partridge Standard for Partridge Plymouth Rocks but kept the UK Standard for Partridge Wyandottes.

I would say that the early Dark (silver pencilled) and Partridge Brahma /Cochins (Asian imports to the west) had mostly Pg, & early Wyandottes (developed in 2nd half/late 1800's) they probably selected for Pg concentric pencilling in hens as a priority. The wild-type Black-breasted Red & Silver Duckwing phenotypes in roosters nothing special (until they prioritized breed type & Exhibition Standards) smile

UK Partridge Wyandottes were exported to Germany in 1906, & not surprisingly, the description suggests these were already double-mated lines. Eg the males were described as having brown edging on the black breast, belly & thighs.

Going by the British Poultry Standard on Barnevelder history, it seems early Barnevelder imports were not set in phenotype colour/pattern, & it seems the English selected for different modifiers than the Dutch, ended up with Barnevelder roosters with patterned /red on the breast. But with the Barnevelders, the UK Standard males actually reflects this pullet-line phenotype, so not a separate cockerel-line black-breasted Barnevelder needed. Yet Dutch Barnevelder males have black breast, double-laced hens.

So I think it more a case of the accumulation & selection of exhibition modifiers over many decades, and whether breeders went for single-mating or double-mating breeding techniques.

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#116215 - 12/01/16 05:28 PM Re: MGB e+/e+ X eb/eb silver pencilled dotte [Re: KazJaps]
KazJaps Offline
Classroom Professor

Registered: 08/30/02
Posts: 2799
Loc: Australia
A terrible blurred photo, but an update on the following F2 chicks:


The paler gold chick is slightly lighter gold than its brother:

* pale gold chick is the one in the middle
As the parents were S/s+ and s+/-, this means the chick just in shot on the right is S/s+ (the gold head at the bottom of photo is their s+/- mother). So I'm confident that the paler gold chick is s+/s+.

So at this stage it "might" appear that the modifier that adds that chick down pale caramel back stripe might be a slight gold diluter to adult plumage.


Edited by KazJaps (10/26/17 06:36 PM)
Edit Reason: temporary update of image links

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#116881 - 10/26/17 07:06 PM Re: MGB e+/e+ X eb/eb silver pencilled dotte [Re: KazJaps]
KazJaps Offline
Classroom Professor

Registered: 08/30/02
Posts: 2799
Loc: Australia
Update...
23 April 2017
F2 chicks - 2 hatched, both female
- e+ s+ (turned out a pullet like F1 mum, Pg/pg+)
- eb/eb S (turned out a pullet, appears pg+/pg+)

*unfortunately I didn't take a photo of these chicks, but I remember the eb S chick looked similar head pattern to the purebred silver Pencilled Wyandotte pullet chicks.

Here she is at 21 weeks old:




-so no signs of salmon on her breast, & plenty of stippling so probably pg+/pg+. Unfortunately the grandfather e+ MGB pullet-line has flitter-lace, so I don't know if her silver lacing is due to the MGB line alone or if a similar mutation was in the Wyandottes.

*note the tick below her wattles. This is a paralysis tick, luckily found it when taking these photos as she was raspy with breathing & starting to wobble on her legs (the toxin can be fatal, can kill dogs, calves let alone a small bantam pullet).

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#116882 - 10/26/17 07:58 PM Re: MGB e+/e+ X eb/eb silver pencilled dotte [Re: KazJaps]
KazJaps Offline
Classroom Professor

Registered: 08/30/02
Posts: 2799
Loc: Australia
28th July 2017 F2 setting
12 chicks hatched
- 2 x eb/eb (1 S, 1 s+, s+ chick died day2)
- 10 x e+/? (6 S, 4 s+)


Here are the 2 eb/eb chicks:

1 x s+ eb:

The eb s+ gold one died early.
--------------
1 x S eb:


*Appears to have at least one dose of the wyandotte dilute modifier (in S silvers it dilutes dorsal central stripe to caramel colour).

Thiz eb S turned out a S/s+ cockerel:
-12 weeks, 5 days old...

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#116883 - 10/26/17 09:16 PM Re: MGB e+/e+ X eb/eb silver pencilled dotte [Re: KazJaps]
KazJaps Offline
Classroom Professor

Registered: 08/30/02
Posts: 2799
Loc: Australia
e+ s+ gold chicks:

Of the other 10 chicks (all e+/?), there were 4 x s+ golds. Three of these golds had very typical e+ wild-type striped chick down, with no obvious modifiers. Two turned out BBRed cockerels, one pullet had probably Pg/pg+, was similar to the F1 hens.

The last chick (pullet) had the dotte-dilute modifier, was very diluted & had reduced e+ stripe on top of head, including modified thin eye-stripe:

* Notice the central back stripe (normally chestnut) is diluted to a slighter darker orangy caramel than the S silver dotte-dilute chicks.

Eg a comparison of the e+ s+ dotte-dilute chick (on left) with the eb S dotte-dilute chick (on right):

So this dotte-dilute mutation is modified by the S locus.

I suspect this e+ s+ dotte-dilute chick is homozygous for the dilute mutation, as the F1 e+/eb s+ gold chicks (all pullets, sex-linked cross) had typical e+ wild-type chick down (chestnut central dorsal stripe), but all the F1 e+/eb S silver chicks (all males) had the dotte-dilute caramel back stripes.

F1 chicks:

* Front S/s+ male, back s+ female. Both heterozygous for the dotte-dilute mutation.

Here is the e+ s+ dotte-dilute pullet now (12 wks, 5 days old), in comparison with her normal e+ s+ sister (with Pg/pg+):


So although this mutation significantly dilutes the chick down it only slightly lightens the gold neck hackles & salmon breast.

But, I also noticed she has a lot of rustiness/burnt orange on her wings.


This is significant as the grandfather e+ MGB BBRed pullet line hens don't have this trait, no rustiness on the wings (this a flaw in e+ MGB exhibition hens).

So I suspect this dotte-dilute mutation is a partial eumelanin restrictor, adds phaeomelanin to the hen's wings/top (might even be on the breast, shading the salmon pigment). I think it is also responsible for the phaeomelanin spots/lace on the Wyandotte rooster's black breast/underside too, but with the F1 roosters, all were black breasted, so needs to be homozygous for adult expression (although one F1 rooster I noticed recently was developing a little flitter on the breast, but this probably from the MGB flitter mutation, increases with adult moults).

Next I will be backcrossing this e+ s+ dotte-dilute pullet to pure e+ s+ MGB roo, & see if this mutation will express when heterozygous on male e+ s+ chicks like occurred with the F1 S/s+ heterozygous male chicks (keeping mind that with central dorsal stripes the S dotte-dilute chicks are lighter than s+ dotte-dilute chicks). This to test if the dotte-dilute mutation is autosomal incompletely dominant sex-influenced (if expressed more in male chicks than female, when heterozygous). And later I might cross her with a S/S e+ MGB silver duckwing rooster, & see again if only the male chicks end up with caramel stripes, or if all of them have caramel stripes (indicating that the F1 differences were due to S locus).

What has been a surprise is that the auto-sexing trait in the purebred eb Wyandotte chicks (males with very little eye-liner markings, females with eye-liner & more pattern) is not occurring with these e+ dotte-dilutes. Both e+ genders have significantly reduced eye-stripes. Maybe the difference is Pg, need both mutations? This dotte-dilute pullet appears to be pg+/pg+.

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