BSO stands for Blue Silver Orange (although some say Blue Shoulder Orange). This color is created by combining blue partridge and dark, and it is still very rare in the United States. Hens have blue penciling on a silver base, often with a rusty tint. Roosters are blue and silver with varying degrees of orange on their shoulder.
Blue does not "breed true" in poultry, meaning two blue parents do not produce all blue offspring. Breeding BSO x BSO also produces Dark Silver Orange (DSO) where blue is replaced with black, and Splash Silver Orange (SSO) where blue is replaced with splash.
As of 2022, we no longer have a dedicated BSO pen. However, in years where we include dark Brahmas in our partridge pen to continue improving our line, BSO and/or DSO will be a resulting byproduct. If you are a fan of BSO hens, our blue dark project may interest you as well. These hens have the same blue penciling as BSO hens but they have a cleaner, brighter silver, resulting in an overall more striking pattern. And if you are interested in breeding your own BSOs, SSOs, or DSOs, you can hatch a variety order of eggs from our partridge and blue dark pens and easily create all three colors in as little as one generation. We are always happy to offer guidance to our customers for arranging breeding groups to produce whichever color(s) you would like to pursue!