need help with silkie genetics

[farmer boy]

i don't get why people don't like cross coloring ... people make it sound like im cross breeding if i cross colors .. saying like its not a pure partridge or something its not like its a different breed right lol silkies are the same just different colors they have fluffy feathers most are docile and they look the same right so why do people make such a big deal about cross coloring ? .. well if jamie says it is part partridge then hes prob right

 

[tadkerson]

First, let me state that Tim knows his genetics at least as well as, and probably more thoroughly than anyone else on BYC. My initial reaction was the same as in his first post here. You can't make partridge from those varieties. The I looked at the photos of parents and offspring, and started rethinking.

The buff looks to have an e^b base rather than E^Wh, I say this because of his dark comb and that he has a fair amount of black in his tail. Thus he could pass e^b on to the next generation.

Many silkies of all varieties have an e^b base, and I would venture to guess that either or both of the hens are at least heterozygous for it. Whether they also have E or E^R would take test breeding or DNA analysis to determine. Being blue they *should* also be laced, whether they are or not is really difficult to say with silkie feathers, but I would speculate that they might have some of the genetic makeup for lacing (PgMl). So Pg could come from the mother, as well as an additional copy of e^b.

This could give some e^b/e^b Pg/pg+ offspring. The same genotype as these specific parents should not be assumed for all buff or blue silkies , and many would NOT give this outcome. Since the original question is about the offspring of the pictured buff rooster and one of the blue hens, but not the pictured offspring, one cannot assume that they inherited e^b/e^b or Pg. You would only know from breeding outcomes or DNA analysis. The potential might be there, but it also might not.

Mixing buff with other colours can give a lot of strange and semi-unique outcomes as there are a number of "recipes" for a buff bird. Without repeatedly selecting for a consistent phenotype, you are simply randomly experimenting,and will not really have a clue what you have genetically.

If you are trying to breed to the standard, you need to know which varieties share what portions of genotype, and breed accordingly. The easiest and simpliest "multi-variety" breeding is blue, black and splash. Next, and it definitely has its drawbacks, is greys and partridge or possibly buff and red (not recognized in silkies).

Tim, please pick apart my analysis and let me know if my reasoning makes sense Thank you!

Suze,

I agree with you. On the first cross the pattern gene would not be expressed in the offspring, it would take another cross (F1 x F1) for the pattern gene to segregate along with the brown allele.

Tim