Genetic Testing - Large Animal

Question 1

What are the requirements to successfully implement genetic testing?

Answer 1

-Understanding that genetics impact trait expression and selection can impact expression
-Understand how genetic selection works
-Have a plan to use the info

Question 2

What are some applications of genetic testing

Answer 2

-Breeding management
-Culling decisions
-Medical guidance
-Rearing management
-Marketing

Question 3

Where does most dairy cattle testing end up

Answer 3

Council on Dairy Cattle Beeding

Question 4

What can be used as a sample?

Answer 4

Hair
Blood
Semen
Tissue
Mucus

Question 5

What are the ways to estimate genetic merit

Answer 5

Parent average - most common, assumes that genes are 50-50 merit inheritance & that parentage is accurate
Genotypic value - based on own performance
Breeding value - based on progeny’s performance
Progeny difference = transmitting ability - value of gamete
Producing ability - performance potential of an individual for a repeated trait (ex. milk, wool quality)

Question 6

Who has the most significant genetic impact on dairy cattle population

Answer 6

Bulls

Question 7

How does genomic prediction work

Answer 7

Reference population (herd) –> phenotypes and SNPs –> association –> individual –> SNPs to predict phenotypes

Question 8

What are the benefits of genomics

Answer 8

-More accuracy in genetic trait and merit prediction
-Merit of young stock is available
-Parentage validation
-Can know carrier status

Question 9

Rate of genetic change equation

Answer 9

Genetic variance - variation in the pop. due to genetics (we can’t change this)
Selection differential - how selective we are
Accuracy - how certain we are about genetic worth, etc

Question 10

What are the major traits selected for in dairy

Answer 10

Production
Conformation
Health

Question 11

What is a total performance index

Answer 11

Combination of multiple traits into a single numerical grade