Ch. 11 Flashcards Preview

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Flashcards in Ch. 11 Deck (22):
1

Selection Index

A linear combination of phenotypic info and weighting factors that is used for genetic prediction when performance data come from genetically similar contemporary group

2

Own Performance Data

Info on an individual's own phenotype

3

Pedigree Data

Info on the genotype or performance of ancestors and(or) collateral relatives of an individual.

4

Progeny Data

Info on the genotype of performance of descendants of an individual

5

Bias

Any factor that causes distortion of genetic predictions

6

Regression for Amount of info

The mathematical process causing genetic predictions to be more or less "conservative" (closer to the mean), depending on the amount of info used in calculating them

7

Unbiased

A genetic prediction is considered unbiased if, as more info is used in subsequent predictions for the same animal, those predictions are as likely to change in a positive direction as they are to change in a negative directions

8

Common Environmental Effect

An increase in similarity of performance of family members caused b their sharing a common environment. Common environmental effects are particularly important within litters (full sibs)

9

Confidence Range

A range of values withing which we expect- with a given probability, a given degree of confidence- that a true value of interest lies.

10

Pedigree estimate

A genetic prediction based solely on pedigree data

11

Best Linear Unbiased Prediction (BLUP)

A method of genetic prediction that is particularly appropriate when performance data come from genetically diverse contemporary groups

12

Large-Scale Genetic Evaluation

The genetic evaluation of large pops- typically entire breeds

13

Field Data

Data that are regularly reported by individual breeders to breed associations or g'vt agencies

14

Statistical Model

A mathematical representation of animal performance that includes various genetic and environmental effects and is used for genetic prediction

15

Animal model

An advanced statistical model for genetic prediction that is used to evaluate all animals (as opposed to just sires) in a pop,

16

Multiple-Trait Model

A statistical model used to predict values for more than one trait at a time

17

Nonrandom mating

Any mating system in which males are not randomly assigned to females

18

Direct component or direct effect

The effect of an individual's genes on its performance

19

Maternal Component or Maternal Effect

The effect of gens in the dam of an individual that influence the performance of the individual through the environment provided by the dam

20

Paternal Component or Paternal Effect

(in rare instances) the effect of genes in the sire of an individual that influence the performance of the individual through the environment provided by the sire. Traits of the dam or offspring that are affected by a male's fertility and physical ability to breed are also said to have a paternal component.

21

Total Maternal Value

A combination of breeding values for both the direct and maternal components of a trait. A female's total maternal value represents the heritable part of her ability to produce a quantity measured in her offspring.

22

Environmental Trend

Change in the mean performance of a pop. over time caused by changes in environment