The Rhodebar thread!

[RedRidge]

So... if you did a similar chart using all RIR hens and only 2 double barred Rhodebar roos, how many generations do you anticipate it would take to assure true autosexing?
I would be curious since you have genetic knowledge to see what that other chart would look like...
I am not 100% convinced the autosexing well remain simply because the barring is correct but this is one of the things I am attempting to determine with my current breeding program.

 

[ortluk]

e+e+ BB (Rhobar Rooster) X e^whe^wh b- (RIR hens)
will result in
e+e^wh Bb (F1 rooster) and e+e^wh B- (F1 Pullets)

If you are using 2 pens then select the best rooster from each pen and put them with the best pullets from the other pen to get your F2 chicks.
Possible roosters(F2)
e+e+ BB, (pure rhodebar)
*e+e+ Bb, (Single Bar)
*e+e^wh BB (Double barred, wrong down color)
*e+e^wh Bb (Single Barred, wrong down color)
*e^whe^wh BB(Double barred wheaton)
*e^whe^wh Bb(Single barred wheaton)
Pullets(F2)
e+e+ B- (pure Rhodebar)
*e+e+ b- (non barred pullet)
*e+e^wh B- (barred, but wrong down color)
*e+e^wh b- (non barred and wrong down color)
*e^whe^wh B- (barred wheaten)
*e^whe^wh b- (nonbarred wheaton, like RIR chicks)

(*culls)
F3
e+e+ BB X e+e+ B- (this cross will breed true and be auto sexing again)

Only about 1 out of 6 chicks in the F2 generation will have all of the proper auto sexing genes, so you will need to hatch at least a dozen from each pen for this cross. If you hatch enough of the second generation from each pen, and cull heavily only breeding the correct down color, and double barred males, your third generation would be back to pure, meaning all of the chicks would be auto sexing and all males would be double barred.
BTW the reason I use two pens is to avoid close inbreeding and hurting fertility rate in the roosters. You could do it with one pen and do a sibling cross if you weren't worried about breeding that close.

 

[nicalandia]

Quote:
RhodeBar Male x HRIR Femal Pen1. Frist cross will produce 100% of the chicks with heterozygous Barring(Hemizygous for females) some of these chicks(the percentage can very, but my limited experience would say around 50%) will look like wildtype chicks(boys will have headspot, females dont) the other chicks will look mostly yellow(not good)... I would separate the best and darker looking barred males(that look closer to RIR) at his point if you are happy with they way they look you can use them directly to good Rhodebar females to produce double barred males OR you can use them to further improve the strain by crossing them back to HRIR females, now the amount of wildtype looking chicks coming from that back cross will be lower than the first cross because some of these chicks will be pure wheaten and the rest will be e+/eWh, as always be in the look out for wildtype looking male chicks(headspot).. these males will be of superior quality than any Rhodebar males you have even seen, their type will close to RIR and their color will be that of a Mahogany Barred Bird, thats because they are only single barred.. but also keep the wildtype looking chicks without headspot, some of these chicks will be non barred males and none barred females, but some(50% of females) will be Barred and these females are basically pure Rhodebars, except they carry one gene of wheaten, they can be use to improve your own stock or to do a sibling cross with the single barred male to produce double barred males

 

[nicalandia]

Quote:
the Numbers to breed from F1xF1 from different pens to get a perfect Rhodebar(with double dose of Mahogany, recessive red enhansers and other modifiers that make RIR so dark) are absurds, to me the best and fastest way to get these traits from the RIR is to breed back to RIR, why? because of the nature of wheaten and Barring... that is wheaten crossed with wildtype will produce some chicks with wildtype chick down and the barring will show on this male chicks as heaspots....

 

[ortluk]

One thing I'm not completely sure on, since I haven't actually done any of these crosses, is the dominance of the wheaton and wild type alleles. Is e+ dominant over e^wh, or are they codominant, meaning that they both express so you can identify heterozygotes?

 

[nicalandia]

Quote:
well there are two types of wheaten, Dominant and recessive but since recessive wheaten is not found on RIR(or at least on great numbers, Dr. Ron Okimoto was able to sequenced recessive wheaten from some lines of RIR) but I am sure 90% of RIR today are "Dominant wheaten eWh" but even dominant wheaten can act as either full recessive or partially co dominant to wildtype, even on same hatchlings.. for example wheaten from Buff cochins is dominant yet when I did a wildtype cross to my buff cochins, some came out looking wildtype and others didnt, and a few in between... but that my friend is good to the Rhodebar breeders... Why? because they know that some e+/eWh chicks will look wildtype and they know how to distinguish them from pure wheaten and this is good because they can carryt he e+ gene further into the RIR genotype which is great as this pure RIR that carry e+/eWh will be good for the Rhodebar project... if e+/eWh didnt look any different from pure wheaten then this could not be possible

 

[nicalandia]

Quote:
you can see a similar cross on the Cream Legbar(autosexing breed like the Rhodebar) hybrid thread, where pics of CLL x RIR can be seen, some of these chicks look wiltype.. le me find the pics for ya edit. from the CCL Hybrid Thread.
Quote:

 

[nicalandia]

my very own e+/eWh cross from same parent.(father ER/e+) mother e+/e+

as you can see 2 of these chicks came out looking wildtype(one more than the other) and one looked almost pure wheaten wile being e+/eWh

 

[ortluk]

Ok,

I can see the value in adding another backcrossing there to solidify some of the Rhode island red traits. So long as you keep selecting for the wild type e+ allele and maintain the barring gene, you could do as many back crosses as you wanted until you have a chick that has the traits from the RIR that your looking for. At that point you still have to breed these improved chicks together to get back to the homozygous e+/e+ and the double factor B/B barring for the roosters, in order for them to be true breeding Rhode bars again.

 

[nicalandia]

Quote:
thats the Idea, keep crossing back to RIR as long as you can pick the e+/eWh chicks from eWh/eWh.. now to the sibling cross after you have achieve the type and color, then it would be a matter of breeding both parents and looking for the double barred males that are e+/e+ this are your ticket. while e+/eWh do look wildtype, e+/e+ chicks look more so, with better defined striping so be in the look out for them too once sibling crossing does accurs and double barred males can be easily picked apart from single barred males at hatch