The Wonders of Horse Coat Color

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The Wonders of Horse Coat Color
Objective 3
Objective 1
Objective 2
The colors of
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The Genetic
The colors
Explanation
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Internet assign.
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Basic Color Determinants

• At 1 loci 3 alleles possible, C, c, and cr.
  The alleles C and cr are co-dominant for skin
  pigmentation. Where C codes for solid color and
  cr codes for mutated color. The allele c is
  recessive and codes for no pigment in the skin.
  However, if both alleles on this loci are c the
  gene becomes lethal. The horse would have been a
  true albino, but it dies before it is ever born.

• At 2 loci 2 alleles possible, B and b. This
  loci codes for skin color. B is black and
  dominant. The recessive b codes for brown.

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Regulation of Pigment

• At loci 4 3 alleles possible, ED, E, and e.
  (Listed in order of dominance.) These genes act
  in conjunction with the genes at loci 1and 2,
  and code for pigment intensity. ED raises the
  intensity of dark pigment. E produces normal
  pigment distribution. The allele e supresses
  black and brown pigments, and increase the
  intensity of the colors yellow and red.
• At loci 5 2 alleles possible, D and d.
  These genes are dilution genes. D is dominant
  and dilutes all colors. The allele d is
  recessive and produces a non-diluted, normal
  coat color.

• At 3 loci 4 Alleles possible, A, A, a, and
  a. (Listed in order of dominance.) The allele A
  codes for a bay hair coat. The allele A is a
  dun or buckskin. The allele a makes the horse
  have tan or red points. The allele a makes the
  horse totally uniform in color.
  

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Searching the Web for horses

• When you get to the internet sight you will want
  to run a search. You may then select what type
  of ad you are looking for, what state it is from,
  what breed of horse you want, what discipline the
  horse is in, etc. Be sure to click the list photo
  ads only box before you run the search!
• Find a horse you like. Look at its picture and
  identify its color. Record this information on
  your worksheet (10a).

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Internet Extension

• Now that you have information about what color
  your internet horse is, pick two loci out of
  the five and try to determine what alleles would
  be present to create your horses coat color (10b
  and c). If you need to go back to the loci
  slides click on the box below.

Loci Info
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congratulations!

• Your worksheet should be filled out (keep it
  until it is collected by the teacher)
• You should have learned the colors of horses
• You should now understand why coat color occurs
• You should have found a horse you like on the web
  and identified its coat color
• You should have also genetically explained the
  internet horses coat color
• CREDITS
• 1. Evans, Warren. Horses. W.H. Freeman and Co.,
  New York, p. 51-4, 580-91.
• 2. Www.horses-for-sale.net/
• 3. Www.mcquaystables.com
• 4. Www.horsesales.com/whitehorse.htm

THE END!!!
YOU SHOULD HAVE HAD FUN!