34) Breeding value: definitions, methods of estimation (BLUP, AM, gBV)

Question 1

List the definitions of breeding value

Answer 1

• Genetic merit
• Breeding value

Question 2

Genetic merit: Types

Answer 2

(Absolute/theoretical value)

Individual, population

Question 3

Breeding value: Types

Answer 3

(Relative/theoretical value)

Individual, population, general, special, aggregated

Question 4

Genetic merit: Definition

Answer 4

• Sum of calculated averages
• According to additive + non-additive allelic effects in each loci
• An individual’s genetic merit is theoretical and remains constant

Question 5

Breeding value: Definition

Answer 5

Deviation of:

• Individual genetic merit from
• Population genetic merit

Question 6

Breeding value: General value

Answer 6

Only additive gene effects are considered

Question 7

Breeding value: Special value

Answer 7

Calculation including:

• Additive gene effects
• Nonadditive gene effects

Question 8

Breeding value: Aggregated value

Answer 8

Complex calculation:

• For more traits simultaneously

Question 9

List the methods of breeding value estimation

Answer 9

• BV
• BLUP
• AM

Question 10

BV

Answer 10

• Breeding value
• The difference between individual and population GM
• Estimated from phenotypic performance

Question 11

Goal of breeding

Answer 11

• Select the best animal for breeding
• Genetically superior to others

Question 12

EBV=

Estimated breeding value

Answer 12

h² x (p_i - p_pop)

• h² = Heritability estimate*
• p_i = Individual phenotypic performance*
• p_pop= Mean of population’s phenotypic performance*

Question 13

Grades of multistage BV estimation

Answer 13

• Ancestral performance
• Collateral performance
• Own performance
• Progeny performance

Question 14

BLUP

Answer 14

• Best linear unbiased prediction
• A complex system of equations used in BV estimation
• General linear mixed model

Question 15

General linear mixed model equation

Answer 15

y = Xβ + Zu + e

• y = Observation vector*
• β​ = Unknown vector*
• u = Non-observed random vector*
• RXZ = Known matrices describing random effects*

Question 16

AM

Answer 16

• Animal model
• Most developed form of the BLUP method
• When more or less pedigree information is available
• Phenotypic performance is adjusted according to degree of relationship

Question 17

Model types used in BV estimations

Answer 17

• Additive
• Nonadditive

Question 18

Additive models

Answer 18

• AM
• BLUP
• Correlation factors
• Classification models

Question 19

Nonadditive models

Answer 19

• Dominance-epistasis
• Cytoplasmic inheritance
• Major genes

Question 20

gBV

Answer 20

Genomic breeding value