Repro Management

Question 1

VWP

Answer 1

Voluntary waiting period

Calving until effort made to AI

Question 2

DOPN

Answer 2

Days open

Calving to conception

Question 3

CI

Answer 3

Calving interval

One calving to next

Question 4

Location length for cows that fail to become pregnant

Answer 4

How much milk she gives over time

Function of peak milk and persistency

Question 5

Benefits of improved repro performance

Answer 5

Lower average DIM- more milk/cow/day
Improved culling options
More calves/replacements produced
Avoidance of fat cow syndrome

Question 6

Improved repro performance costs

Answer 6

More transition cows
Higher feed costs
Repro program costs

Question 7

Repro management basic approaches

Answer 7

AI- rapid genetic progress, synchronization, less dangerous
Natural service- easier
Combo- clean up bull

Question 8

Normal Inestrus period

Answer 8

18-25 d (21 heifer, 23 cow)

Question 9

Standing estrus

Answer 9

5-8hrs
Differences due to milk production and how quickly estradiol is removed from circulation
Cows avg 6-9 mounts with 25sec standing/estrus
Stand better in dirt

Question 10

Estrus detection

Answer 10

Watch for 30 min 3x per day
Kamar, estrus alert, heat watch
Pedometer, goner bull, chin-ball marker
Tail paint/chalk

Question 11

IR

Answer 11

Insemination risk
Bred/eligible for breeding
35-70%, avg 48%, goal >65%

Question 12

CR

Answer 12

Conception risk
Conceived/bred
25-45%, avg 33% Goal is >40%

Question 13

Pregnancy rate

Answer 13

Pregnant/eligible per 21d period

Question 14

Poor display of estrus

Answer 14

High milk prod associated with shorter, less intense displays of estrus

Question 15

Challengers with low conception risk

Answer 15

CR in lactating cows 1/2 of heifers (35 v 60%)

High milk prod reduced CR

Question 16

Challenges for repro

Answer 16

Poor display of estrus
Low conception risk
Prolonged a estrus
Embryonic/fetal wastage

Question 17

Primary bottleneck to improving reproduction

Answer 17

Low insemination intensity

Question 18

GnRH

Answer 18

Factrel
Induces ovulation/lute ionization of dominant follicle
Initiates new follicular wave by remove influence of current dominant follicle

Question 19

hCG - human chorionic gonadotropin

Answer 19

LH like - induce ovulation of responsive follicle

Question 20

Estrogen

Answer 20

Illegal in dairy cows, no longer commercially available

Question 21

PGF2a

Answer 21

Lutalyse

Removes CL-drop in progesterone

Question 22

Progestagens

Answer 22

CIDR

Mimics presence of CL

Question 23

Ovsynch

Answer 23

0-GnRH, removes dominant, new wave
7-prostaglandin, removes CL, mat of dominant
56h later- GnRH, ovulation of dominant (28h)
12-16h- TAI

Question 24

PR

Answer 24

Pregnancy rate
Pregnant/eligible for 21 d
12-18%, 16%, goal >24%

Question 25

PR influenced by

Answer 25

Insemination risk- cyclicity, detection, TAI protocols

Conception risk- detection, semen, health of repro tract