The Silkie ChickenSilkies originated in the Far EastBantam BreedDark skin tone and 5 toes instead of the

normal fourAre wonderful “brooders” and have been

known to adopt baby geese/ducks if given the chance

Silkie Colors

Silkies come in a large variety of colors.Black, Blue, and Splash are all on the same

chromosome- we will deal with these colors in our study

Splash Hen (Ophelia)

Blue Rooster (Nelson)

Splash Rooster (Cockatoo)

Black Hens (Peach & Petunia)

“Broody” Blue Hens

Other ColorsOther colors include buff, lavender, white,

and partridge, but those colors are located on multiple chromosomes

Color GeneticsBlack, Blue, and Splash are located on the

same chromosome and are controlled by two different alleles.

We use the letters “B” and “b” to represent the alleles

Genetic Control of ColorBB = Blackbb = SplashBb = Blue

What do we call this???

Incomplete Dominance/ Blending Inheritance

Problem #1What color(s) of offspring would you predict

from a cross between a splash silkie rooster and a blue silkie hen?

b b

B Bb Bb

b bb bb

Problem #2What color(s) offspring would you expect to

get from a blue silkie rooster crossed with a blue silkie hen?

B b

B BB Bb

b Bb bb

Problem #3What color(s) offspring would you expect

from a cross between a slash silkie rooster and a splash silkie hen?

b b

b bb bb

b bb bb

Problem #4What color(s) offspring would you expect

from a cross between a blue silkie rooster and a black silkie hen?

B b

B BB Bb

B BB Bb

Quiz1. Is it possible for a black chick to be born from

a splash rooster?

2. What color(s) of parents could produce the splash phenotype?

3. Can you tell the genotype of the heterozygous vs. the homozygous dominant silkie chicken? Explain.

4. Show the Punnett Square for a cross between a blue rooster and a splash hen.

5. List the % of the genotypes and phenotypes that would result from that cross.

Calculating ProbabilityTo calculate probability, we have to

determine all of the potential crosses that are possible

1.Blue Rooster x Blue Hen2.Blue Rooster x Black Hen3.Blue Rooster x Splash Hen4.Splash Rooster x Blue Hen5.Splash Rooster x Black Hen6.Splash Rooster x Splash Hen

Calculating ProbabilityThen we calculate the ratios of each color of

offspring from each potential cross (Black: Blue: Splash)

1.Blue Rooster x Blue Hen = 1:2:12.Blue Rooster x Black Hen = 2:2:03.Blue Rooster x Splash Hen = 0: 2: 24.Splash Rooster x Blue Hen = 0: 2: 25.Splash Rooster x Black Hen = 0: 4: 06.Splash Rooster x Splash Hen = 0: 0: 4

Calculating ProbabilityNext, we add all of the ratios to calculate a

final ratio of predicted chick coloringBlack : 1+2 =3Blue : 2+2+2+2+4 = 12Splash : 1+2+2+4 = 9

Final Ratio = 3:12:9

Calculating ProbabilityNow we can calculate our predicted

probabilities of each color based on our ratio3+12+9 = 24

(3/24)*100 = 12.5% Black(12/24)*100 = 50% Blue(9/24)*100 = 37.5% Splash

Later, we will calculate our percent error to see how accurate these predictions were!