Blue Marans, Splash Marans
Splash Marans
The blue colored varieties have existed in the Marans breed since its origins, i.
e. Blue was introduced at the first crossing with it’s English Game ancestors. At
this time I can find no country that has accepted a Blue or Splash as a separate
variety, but the process is under way in several.

The Blue gene is a dominant gene with variable penetration that dilutes black
pigment, when present in either the homozygous Bl/Bl, or the heterozygous
Bl/bl+ states. In the heterozygous state, Bl/bl+ dilutes black to a bluish/gray
color, this blue color produces a variety of shades in the plumage, ranging from
‘pigeon egg blue’ to a dark ‘navy blue’, often with some blackish feathers
scattered here and there, but has no effect on gold/red pigments.

Homozygous Blue Bl/Bl creates an even greater dilution effect, producing a
Splashed White (Splash) bird. This plumage is white with the odd blue feather; it
is known in Europe as “dirty White” This is very different from both the Dominant
White and the Recessive White, both of which have the effect of converting
black to white.

It is important to understand that:
Blue does not breed true but gives the following results,

A Blue to Blue, Bl/bl+ X Bl/bl+ mating will give 25% Splash,
Bl/Bl; 50% Blue, Bl/bl+ and 25% Black bl+/bl+

A Splash to Black, Bl/Bl X bl+/bl+ mating gives 100% Blue,
Bl/bl+

A Blue to Black mating, bl+/bl+ X Bl/bl+, gives 50% each
Blue, Bl/bl+ and Black bl+/bl+.

Blue should not be confused with recessive Lavender,
which dilutes both black and red, and is true breeding.
Lavender dilutes black to a "pearl gray color" producing a
very uniform plumage colour. The  "pearl-gray color" is not
found in Marans.

The genome of the heterozygous Blue Marans cock is E/E
S/S Ml/Ml Bl/bl+ Id/Id W/W Pti-1/Pti-1 and that of the hen is
E/E S/- Ml/Ml Bl/bl+ Id/- W/W Pti-1/Pti-1.

The varieties based on the Extended Black allele may
mask all other allele in the series.
David Hancox
Information on the Blue Marans was obtained from  
http://maransofamericaclub.com
_______________________________________
Information on Blue Genetic Breeding Made Simple:

Blue (Bb) X Blue (Bb) = 50% Blue (Bb), 25% Black (BB), 25% Splash (bb)
Blue (Bb) X Splash (bb) = 50% Blue (Bb), 50% Splash (bb)
Blue (Bb) X Black (BB) = 50% Blue (Bb), 50% Black (BB)
Splash (bb) X Black (BB) = 100% Blue (Bb)
Black (BB) X Black (BB) = 100% Black (BB)
Splash (bb) X Splash (bb) = 100% Splash (bb)
This is our largest Blue Marans egg
to date -  3.153 oz -
Blue Black and Splash Marans
day old chicks
We are very pleased with the eggs we are producing from our Blue Marans.  While not as dark as
our Black Copper Marans (about  5-7 on the
Marans scale)  they consistently lay extra large eggs
usually beginning with the second laying season.  Although we breed to the French standards and
all our Marans are feather shanked they still throw chicks from time to time with clean legs.

The color of the Blue Marans can be a little inconsistent.  The rule of the blue genetics applies to this
breed as well
(see the info below on breeding blue to blue) you could get blue, black or splash
chicks.   We have also seen them occasionally throw
blue copper and some black with coppering.