Light Chest on Silver Cockerels

[Steve Neumann]

   One out of four of my Silver cockerels has a really light chest (the one on the left). I'm new to this variety.  What, genetically, causes this? 

[John W Blehm]

I see it on occasion with silvers and think there is Columbia (Co) or Darkbrown (Db) hiding in the lines/strains.  One copy of either gene will move black out of the male's breast area.  With a dominant gene like those it seems like it would be easy to breed out.  My best guess is females hide it and are used as breeders.  Since I don't take the time for test mating, I just don't breed from males that show it. 
Other ideas?

[Steve Neumann]

So, conceivably, if this cockerel had the best type and comb of the four I have to choose from, I could use him, and ONLY keep cockerels with black chests out of him?  I'm just trying to figure out if I should cull this guy now or if he might be useful and I should hang on to him.

[Mike Gilbert]

So, conceivably, if this cockerel had the best type and comb of the four I have to choose from, I could use him, and ONLY keep cockerels with black chests out of him?  I'm just trying to figure out if I should cull this guy now or if he might be useful and I should hang on to him.

You could do that, but don't forget he will pass on the undesired trait to about half his sons and also daughters - who won't show it because the gene does not seem to affect female coloration.
Another route to go would be to test mate each of your female breeders individually to find out which ones are carriers - and eliminate them and their offspring.

[John W Blehm]

The two genes, I mention above, as possible candidates are "incompletely dominant" genes, so they aren't completely dominant.  The reason I said "I think" and asked for other ideas is that I don't want anyone to take what I said as fact, but rather guesses or IMO as they say.

Sellers, Autosomal Linkage Group 3 Genes

Dark brown, Db Incompletely dominant. Changes black down of E, E^R to reddish-brown. Adults males exhibit a Columbian-type pattern of black, modifies red to orange-tan. Db is a better restrictor of black in males than females.

This seems like a possible candidate and maybe those pullets/hens with a lot of white in their upper breast area are carriers...just another guess.  I haven't bred from cockerels/cocks with much white in their breasts, but now I'll be even more selective of my female breeders going on the assumption that Db may be what I'm seeing.

You've got some of our thoughts and there are other sites that I suggest when it comes to genetics research.     

[Steve Neumann]

Thanks for the advice