14: Genetic Resemblance pt2 Flashcards
GCV cannot be inherited but is maintained through…
mating strategies
Outbreeding results in increased
GCV (favourable gene combination)
E.g. of breed complementarity
Gir cattle mixed with holstein cattle
Have hybrid vigor, adaptability, good milk production in hot climates, quiet disposition
What is the most common relationship in a pedigree
Half siblings due to fixed time artificial insemination
What is the coefficient of inbreeding
The probability that both genes of a pair in an individual are identical by descent
How do common ancestors affect coefficient of inbreeding
Each CA contributes a separate probability that the alleles in animal X are copies of the same ancestral alleles
Coefficient of inbreeding range
0 (no inbreeding) to 1
Fx
Fx equation
Fx = (1/2)^(n1+n2+1) (1+Fca)
Slide 16
What is Fca
inbreeding coefficient of the common ancestor
What are the n’s in the Fx equation
Number of generations separating the CA from the dam and sire
First step to calculating coefficient of inbreeding
Identify unique paths through parents of animal X
Second step to calculating coefficient of inbreeding
Sum the values of all unique paths
Relationship definition
Probability that a randomly taken allele from individual X is identical by descent to a randomly taken allele from individual Y
What is Wright’s Coefficient of Relationship (Rxy)
Probable proportion of one individual’s genes (X) that are identical by descent to genes of a second individual (Y)
Rxy range
0 (completely unrelated) to 1 (identical twins)
