Ch. 7 Flashcards Preview

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Flashcards in Ch. 7 Deck (24):
1

Quantitative Genetics

The branch of genetics concerned w/ influences on, measurement of, relationships among, genetic prediction for, and rate of change in traits that are or can be treated as quantitative.

2

Phenotypic value (P)

A measure of performance for a trait in an individual- a performance record

3

Population Mean

The avg. phenotypic value of all individuals in a population.

4

Genotypic Value (G)

The effect of an individual's genes (singly & in combination) on its performance for a trait.

5

Environmental Effect

The effect that external (nongenetic) factors have on animal performance.

6

Value

(in animal breeding) Any measure applied to an individual as opposed to a pop. Exs. are phenotypic value, genotypic value, breeding value, & environmental effect.

7

Breeding value

The value of an individual as a (genetic) parent

8

Independent Gene Effect

The effect of a gene independent of the effect of the other gene at the same locus (dominance) and the effects of genes at other loci (epistasis)

9

Breeding Value

The part of an individual's genotypic value that is due to independent and therefore transmittable gene effects.

10

Estimated Breeding Value

A prediction of a breeding value

11

Progeny Difference (PD) or Transmitting Ability (TA)

Half an individual's breeding value- the expected difference between the mean performance of the individual's progeny and the mean performance of all progeny (assuming randomly chosen mates)

12

Expected Progeny Difference (EPD), Predicted Difference (PD), or Estimated Transmitting Ability (ETA)

A prediction of a progeny difference

13

Additive Gene Effect

independent gene effect

14

Additive Genetic Value or Additive Value

Breeding value

15

Gene Combination Value (GCV)

The part of an individual's genotypic value that is due to the effects f gene combinations (dominance and epistasis) and cannot, therefore, be transmitted from parent to offspring

16

Gene Combination Effect

The effect of a combination of genes, i.e. a dominance or epistatic effect

17

Nonadditive Gene Effects

Gene combination effects

18

Nonadditive Genetic Value or Nonadditive Value

Gene combination value

19

Repeated trait

A trait for which individuals commonly have more than one performance record.

20

Producing Ability (PA)

The performance potential of an individual for a repeated trait.

21

Permanent Environmental Effect

A environmental effect that permanently influences an individual's performance for a repeated trait.

22

Temporary Environmental Effect

An environmental effect that influences a single performance record of an individual, but does not permanently affect the individual's performance potential for a repeated trait

23

Most Probable Producing Ability (MPPA)

A prediction of producing ability

24

Threshold

A point on the continuous liability scale for a threshold trait above which animals exhibit one phenotype and below which they exhibit another