Ultrasound In Dairy Practice

Question 1

What are US used for in diary cattle?

Answer 1

Access ovarian function
Dx pregnancy earlier
Detect twins
Determine fetal viability
Visualize pathology

Question 2

Important US images

Answer 2

Early signs of fetal dz
Congenital fetal abnormalities
Ovarian and uterine pathology
Fetal sexing

Question 3

Hyperechoic

Answer 3

Greater reflection of waves
Bones and other dense tissue

Question 4

Hypoechoic

Answer 4

Fewer waves reflected
Soft tissue

Question 5

Anechoic

Answer 5

Appears black
No waves returned
Fluid (early pregnancy)

Question 6

Pregnancy can be detected as early as ____________

Answer 6

25-26d (now about 30-35)
allows for early resynchronization for open cows

Question 7

Why are recheck exams essential?

Answer 7

EED rates of 8-10% for single pregnancies and 25% for twin pregnancies

Question 8

Heartbeat is detected ________ gestation

Answer 8

28d
lack of heart beat= fetal demise

Question 9

Detection of fetal viability

Answer 9

Echogenic debris within CA or amniotic fluid
Separation of fetal membranes from the wall of uterus
Irregularly shaped or hyperechoic embryo

Question 10

ID of non viable fetus allows ____________

Answer 10

Quicker return to breeding eligibility (could be in there for days or weeks)

Question 11

Examples of congenital anomalies

Answer 11

Multiple headed fetuses
Schistosomus reflexus
Anasarca

Question 12

Fetal gender determination

Answer 12

Producers use to make management decisions: neonatal management, culling and AI contracts
55-90d gestation

Question 13

What does fetal determination depend on?

Answer 13

Genital tubercle (migration complete by 55d)

Question 14

Female genital tubercle

Answer 14

Bi-lobed, hyperechoic structure under the tail of bovine after 55d gestation

Question 15

Male genital tubercle

Answer 15

Hyperechoic structure located immediately caudal to the umbilicus

Question 16

Fetal aging

Answer 16

More precise prediction with unknown
More accurate than palpation alone
After 128d US less accurate for aging

Question 17

Embryo is 1cm in length at _______

Answer 17

28d

Question 18

Trunk diameter

Answer 18

Widest part of the rib cage at the level of umbilicus

Question 19

Biparietal diameter

Answer 19

Maximum diameter of the skull @ the level of the eyes

Question 20

Crown-rump length (CRL)

Answer 20

Up to 50d gestation age:
CRL (mm) + 18 = fetal age in days

Question 21

Head length

Answer 21

Measures from crown of head to tip of nose

Question 22

3 yr-old Holstein cow for pregnancy dx. Image of the tip of the uterine horn and ovary. What condition and therapy?

Answer 22

Presence of purulent fluid in uterine lumen
Prolonged lifespan of CL due to failure of leuteolysis
Tx: luteolytic dose of PGF2a

Question 23

4 yr-old Holstein @ 85 DIM. What structures are seen? The other ovary is static and cow hasn’t shown signs of estrus. Management?

Answer 23

Anovular condition (no luteal tissue)
May exhibit repeated estrus
Tx: GnRH +/- TAI protocol

Question 24

2 yr-old crossbred beef cow for pregnancy dx @ 110d after AI. IS this fetus normal? If not, abnormalities?

Answer 24

Fetal Ascites/ Anasarca

Question 25

Ovarian enlargement ruleouts?

Answer 25

Granulosa Cell tumor- dx with AMH (produced by granulosa cells within DF)