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Flashcards in Ch. 2 Deck (29):
1

The purpose of animal breeding

to genetically improve populations of animals

2

tools used by animal breeders

selection and mating

3

Mating*

the process that determines which selected males are bred to which selected females

4

Two types of selection

natural and artificial

5

Natural selection

evolutionary force and survival of the fittest

6

artificial selection

Has human control by replacement selection and culling

7

Replacement selection

young animals, replacing older animals. (involved A.I. and E.T.)

8

Culling

25-30% yearly cull rate recommended for livestock

9

goal of selection

individuals w/the best set of genes reproduce so the next generation (on avg.) has more desirable traits than the previous generation. Individuals w/ the best set of genes have the best breeding value

10

Heritability

a measure of the strength of the relationship between breeding values and phenotypic values for a trait in a population

11

Performance testing *

systematic measurement of performance in a population. It varies among species and breeders in a species. Usually seedstock producers participate

12

Dairy Herd Improvement Association (DHIA)

Established in 1965 it collects and processes info on dairy cows for 1/3 of the US producers.

13

Pedigree Data *

info on the genotype or performance of ancestors and/or collateral relatives of an individual

14

Progeny data *

info on the genotype or performance of descendants of an individual. Can also be used to predict breeding values.

15

A pedigree contains

performance data and genetic predictions

16

Accuracy*

a measure of the strength of the relationship between true vales and their predictions (also called repeatability or reliability)

17

genetic predictions*

the area of animal breeding concerned with measurement of data, statistical procedures, and computational techniques for predicting breeding values and related values.

18

sire summaries*

a list of genetic predictions, accuracy values, and other useful info about sires in a breed

19

Polygenic traits*

traits that are affected by many genes w/no known single [major] gene having an overriding influence

20

Simply-inherited trait*

a trait affected by only a few genes

21

between-breed selection*

the process that determines the breed(s) from which parents are selected

22

Complementarity*

An improvement in the overall performance of offspring resulting from mating individuals w/ different but complementary breeding values

23

crossbreeding*

the mating of sires of one breed or breed combination to dams of another breed or breed combination.

24

Hybrid Vigor or Heterosis*

an increse in the performance of hybrids over that of purebreds.

25

what are the most common improvements?

fertility and survivability

26

Inbreeding*

The mating of relatives

27

Inbreeding Depression*

A decrease in the performance of inbreds, most noticeably in traits like fertility and survivability

28

Line breeding

Careful inbreeding within lines can be useful to produce heterosis when crossing w/other lines (outbreeding)

29

Corrective mating*

A mating designed to correct in their progeny faults of one or both parents