Exam 1

Question 1

any observable or measurable characteristic of an individual

Answer 1

trait

Question 2

trait questions

Answer 2

what color are they?
what kind of growth do they have
how tall are they

Question 3

an observed category or measured level of performance for a trait in an individual

Answer 3

phenotype

Question 4

phenotype examples

Answer 4

red coat color
576 pounds meaning weight
15.1 hands tall

Question 5

” a bad temperament”
which is the trait and which is the phenotype

Answer 5

temperament or disposition is the trait ( what is being measured
bad in the phenotype (the measurement)

Question 6

presence of horns, yearling weight, placing, shell color, quarter mile times, calving ease, litter size

Answer 6

traits

Question 7

horned, polled, scurred, dehorned, 850lbs, first, white, brown, 19.3 seconds, assisted

Answer 7

phenotypes

Question 8

the genetic makeup of an animal

Answer 8

genotypes

Question 9

a classification for animals with similar genotypes for traits of interest (heavy type draft horses, prolific wool type sheep , all-purpose type cattle)

Answer 9

biological type

Question 10

a group of interdependent parts ( single farm - animals, facilities, fixed resources, management)

Answer 10

system

Question 11

a dependent relationship among components of a system in which the effects of any one component depend on other components present in the system

Answer 11

interaction

Question 12

a dependent relationship between genotypes and environments in which the difference in performance between two (or more) genotypes changes from environment to environment

Answer 12

G x E interactions

Question 13

A general goal for a breeding program- a notion of what constitutes the best animal ( parasite resistance in tropical areas and brisket disease resistance in high elevations)

Answer 13

breeding objectives

Question 14

Facets of the US beef industry

Answer 14

seed stock (genetics) , cow-calf (weaned market calves, replacement females, cull bulls, cull cows) , backgorunding-stocking (feeder calves and light weight weaned calves) , feed yard (finished steers and heifers), processing (retail beef and hides)

Question 15

if Perkins could get rid of one facet

Answer 15

backgrounding- stocking

Question 16

what must you know before selecting your genotypes

Answer 16

resources, expenses, income, and environment

Question 17

should producers strive to produce the highest level of one given trait

Answer 17

no, NEVER single trait select

Question 18

what does intermediate optimum do

Answer 18

maximized profitability and/ or function ( pastern angle in cattle, horses, and pigs)

Question 19

genetic material in the form of live animals, embryos, semen, blood, or tissue

Answer 19

germ plasm

Question 20

% of cattle quality

Answer 20

69% commercial
30% premier
1% elite

Question 21

genotype of jersey

Answer 21

small size, moderate feed intake, moderate yield, high butterfat

Question 22

genotype of Holstein

Answer 22

larger size, high intake, high yield, low buttrfat

Question 23

a group of intermating individuals. can be a breed, species, a herd, or a group of animals in a herd

Answer 23

population

Question 24

animal breeding is all about improving an individual animal

Answer 24

false; an entire population

Question 25

the process that determines which individuals become parents, how many offspring they produce, and how long they remain in the breeding population

Answer 25

selection

Question 26

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

Answer 26

mating

Question 27

traits for beef cattle

Answer 27

pregnancy.....pelvic area calving ease .....feed conversion birth weight.....scrotal circumference weaning weight ..... breeding soundness yearling weight .....fat thickness mature weight.....ribeye area hip height ..... marbling ( intramuscular fat)

Question 28

traits for dairy cattle

Answer 28

days dry calving interval services per conception milk yield % fat in milk % protein in milk

Question 29

traits for horses

Answer 29

wither height .....time to trot 1/4 mile mature weight .....time to run 1 mile time to trot 1-mile.....weight started (draft) placing ..... cutting score winnings ..... fleshing ability

Question 30

traits for pigs

Answer 30

pregnancy..... 21-day litter weight litter size (born alive) ..... days to 230 lbs litter size (weaned).....feed conversion weaning weight.....loin eye are marbling .....fat thickness

Question 31

traits for chickens

Answer 31

number of eggs in one year .....egg weight hatchability .....feed conversion ratio hot carcass weight .....mature body weight shank length ..... breast weight breast muscle area .....woody breast disease

Question 32

traits for sheep

Answer 32

pregnancy ..... number born 60-day weight .....feed conversion birth weight .....scrotal circumference yearling weight ..... breeding soundness staple length ..... loineye area clean fleece weight .....grease fleece weight `

Question 33

the measure of the relationship between the breeding value of a trait and the phenotype or expression of the trait

Answer 33

heritability

Question 34

the value of an individual as a parent

Answer 34

breeding value

Question 35

performance testing levels

Answer 35

on-farm regional state association

Question 36

a trait affected by many genes

Answer 36

polygenic

Question 37

a trait affected by a few genes

Answer 37

simply inherited trait

Question 38

what is the major gene

Answer 38

H-Y histocompatibility gene on the short arm of the Y chromosome

Question 39

British/English cattle

Answer 39

Angus, short horn, Hereford, galloways

Question 40

European cattle

Answer 40

Charolais, limousine, Simmental

Question 41

Bos taurus vs bos indicus

Answer 41

Bos Taurus: non humped, cool environment Bos indicus: hot, humid environment (zebu)

Question 42

a set of rules for mating animals

Answer 42

mating system

Question 43

mating system examples

Answer 43

large to small largest to largest Sorrell to cremello Charolais to Angus half brother to half-sister ( genetic defect will be exposed and lower BWT)

Question 44

mating animals that are different yet complementary of each other for improved genetics, marketing value, etc.

Answer 44

complementarity

Question 45

mating of animals less closely related to each other than the average relationship in the population

Answer 45

crossbreeding

Question 46

what happens to hybrid vigor and heterosity with crossbreeding

Answer 46

increases

Question 47

increased performance of the crossbred offspring over the performance of either purebred parent

Answer 47

hybrid vigor-heterosis

Question 48

what can cause hybrid vigor to be negative

Answer 48

inbreeding depression

Question 49

mating of animals more closely related to each other than the avg. relationship in the population

Answer 49

inbreeding

Question 50

the opposite of heterosis; decrease in fitness with increased genome-wide homozygosity that occurs in the offspring of related parents.

Answer 50

inbreeding depression

Question 51

history of livestock measurement

Answer 51

1. average daily gain 2. within herd ratios 3. most probable producing ability 4. estimated breeding value 5. expected progeny difference 6. genomic enhanced EPD

Question 52

what accuracy do young animals have originally and how much does it increase with genomic enhanced epd's

Answer 52

.05 originally increases by .3

Question 53

what does progeny equivalence do to accuracy

Answer 53

increases it

Question 54

combination of parental expected progeny difference and individual performance for a given trait.

Answer 54

expected progeny differences

Question 55

what do EPD's include

Answer 55

differences in expected performance of future progeny as well as individual performance for a given trait.

Question 56

what traits are EPD's calculated for

Answer 56

growth, reproduction and body composition

Question 57

normal curve for epd values

Answer 57

68%: -1 +1 95%: -2 +2 99%: -3 +3

Question 58

heritability for reproduction traits ( low)

Answer 58

< .20

Question 59

heritability for growth traits ( moderate)

Answer 59

.20-.39

Question 60

heritability for carcass traits ( high)

Answer 60

> .40

Question 61

a group of cattle of the same breed and sex, born in the same season at the same location, managed alike from birth to the time of measurement

Answer 61

contemporary groups

Question 62

effects of proper contemporary groups on environmental effects

Answer 62

minimizes them

Question 63

how are differences expressed within contemporary groups

Answer 63

as ratios

Question 64

why do EPDs change

Answer 64

1. improper sampling 2. genetic by environment interaction 3. changes in the sire and dam EPDs 4. additional progeny data * 3 and 4 change daily

Question 65

beef production economics

Answer 65

reproductive efficiency maternal ability early growth longevity end product merit

Question 66

how do you account for antagonistic genetic correlations

Answer 66

minimize them because you cannot totally avoid them

Question 67

what must you do when using carcass merit EPDs

Answer 67

define the target

Question 68

what is not a good idea if you are retaining replacement heifers

Answer 68

remove the ability to deposit fat needed for reproduction

Question 69

selection considerations

Answer 69

- use EPDs as a selection tool - determine your genetic strengths and weaknesses -balance reproduction, calving ease, growth rate, cow size, and carcass merit -know your market opportunities -keep the consumer in mind when making decisions

Question 70

BLUP

Answer 70

best linear un-biased pedictors

Question 71

what is the normal distribution curve for

Answer 71

binomial distributions; comparing 2 bulls progenys

Question 72

how often to EDPs change

Answer 72

angus: once a week other breeds: per season

Question 73

do not select below 50th percentile if..

Answer 73

trait is of importance