nicalandia what do you think of the Hagedoorn method of breeding autosexing.. ?
Creating autosexing birds that already carry the wildtype e allele(e+) its a NO BRAINER, nothing special about that, and as you can see all he did was introduce the barring gene and kept crossing it back to pure Barnevelder untill he got back to good type and color, then what he did in order to get true breeding autosexing was to select single barred males and mate them to the barred females thats all, nothing special about that.
now Breeding good Quality Rhodebars is Way more complex than that, why? because RIR are wheaten at the e locus(eWh) instead of the wildtype e locus(e+) the Rhodebar carry, so its more complex...
why? wheaten is a very unstable e allele, meaning that if you cross wheaten and wildtype you would expect all of the chicks to be wheaten heterozygotes and thats true, but just how does a wheaten heterozygote looks like? thats the issue, some look like pure wildtype(chipmunk) some look like pure wheaten(yellow/orange chick down) and some will come out looking right in the middle like a yellow looking chipmunk chick...
but if I were doing the cross I would cross a Rhodebar male over a good quality RIR hatch over 15 eggs, select the chicks that look wildtype or close to it. be in the look out for males, cross them back to a few good quality RIR and hatch 25+ eggs, why? because most of the chicks will come out wheaten looking and the few that come out as close to wildtype will be a mix of barred and none barred birds so hatching as many as you could is the best way to go about it. reapeat the process till you are happy with body and type and then cross barred male with barred females and be in the look out for the doulbe barred male, this is your ticket for autosexing
this can also be apply to the Hampbar breeding programe