The Silkie Chicken
 Silkies originated in the Far East
 Bantam Breed
 Dark skin tone and 5 toes instead of the normal four
 Are 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 Colors
 Other colors include buff, lavender, white, and
partridge, but those colors are located on multiple
chromosomes
Color Genetics
 Black, Blue, and Splash are located on the same
chromosome and are controlled by two different
alleles.
 We use the letters
alleles
“B” and “b” to represent the
Genetic Control of Color
 BB = Black
 bb = Splash
 Bb = Blue
 What do we call this???
 Incomplete Dominance/ Blending
Inheritance
Problem #1
 What 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 #2
 What 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 #3
 What 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 #4
 What color(s) offspring would you expect from a cross
between a blue silkie rooster and a black silkie hen?
B
B
B
BB
b
Bb
BB
Bb
Quiz
1.
2.
3.
4.
5.
Is it possible for a black chick to be born from a
splash rooster?
What color(s) of parents could produce the splash
phenotype?
Can you tell the genotype of the heterozygous vs. the
homozygous dominant silkie chicken? Explain.
Show the Punnett Square for a cross between a blue
rooster and a splash hen.
List the % of the genotypes and phenotypes that
would result from that cross.
Calculating Probability
 To calculate probability, we have to determine all of
the potential crosses that are possible
1. Blue Rooster x Blue Hen
2. Blue Rooster x Black Hen
3. Blue Rooster x Splash Hen
4. Splash Rooster x Blue Hen
5. Splash Rooster x Black Hen
6. Splash Rooster x Splash Hen
Calculating Probability
 Then we calculate the ratios of each color of offspring
from each potential cross (Black: Blue: Splash)
1. Blue Rooster x Blue Hen = 1:2:1
2. Blue Rooster x Black Hen = 2:2:0
3. Blue Rooster x Splash Hen = 0: 2: 2
4. Splash Rooster x Blue Hen = 0: 2: 2
5. Splash Rooster x Black Hen = 0: 4: 0
6. Splash Rooster x Splash Hen = 0: 0: 4
Calculating Probability
 Next, we add all of the ratios to calculate a final ratio of
predicted chick coloring
 Black : 1+2 =3
 Blue : 2+2+2+2+4 = 12
 Splash : 1+2+2+4 = 9
 Final Ratio = 3:12:9
Calculating Probability
 Now we can calculate our predicted probabilities of
each color based on our ratio
 3+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!