Pregnancy Diagnosis

Question 1

what is the purpose of pregnancy diagnosis (5)

Answer 1

-Every “day open” costs a dairy producer $4 to $5
-Earlier diagnosis = earlier opportunity to rebreed
-Planning help for calving/foaling/lambing
-Nutrition
-Herd management

Question 2

potential pregnancy tests (7)

Answer 2

-History of breeding
-Non-return to estrus
-“She looks pregnant” = Udder development and abdominal enlargement
-Blood tests for “pregnancy factors”
-Hormonal analysis
-Palpation of the uterus
-Ultrasonography of the uterus

Question 3

possible reasons for a false positive pregnancy

Answer 3

Inaccurate estrus detection
-Missed estrus
-Not knowing signs of estrus

Prolonged diestrus or anestrus
-Cystic ovarian disease in cows
-Up to 20% of mares may have a prolonged luteal phase

Signs of estrus in early pregnancy (~5%)

Question 4

are false pregnancies common in horses

Answer 4

no

Question 5

causes of false pregnancy diagnosis

Answer 5

-Canine – may show mammary development, lactation and nesting behaviour
-Caprine – develop enlarged abdomen, uterus full of fluid (“cloud burst” or mucometra)

Question 6

what pregnancy associated glycoprotein are tested in blood

Answer 6

PAGS

Question 7

biopryn test; what does it look for, species it can be used in

Answer 7

-For Pregnancy-Specific Protein B (one of many PAGs)
-Cows, Sheep, Goats

Question 8

PAG protein B production

Answer 8

-produced by binucleate trophoblast cells from about 28 days of pregnancy

Question 9

what is the issue with biopryn test in cows

Answer 9

it persists in blood of cows up to 73 days postpartum = so keep in mind based on if the cow you are testing is PP

Question 10

when to use biopryn test + limitations

Answer 10

-Uses: after 73 days postpartum and for cows 30 days or more after insemination
-Limitations: send out blood, lab delays, cost
-Re-check recommended due to false positives and EED

Question 11

D29 blood test; when it is used, what does it look for, species it can be used in

Answer 11

-Used as early as 29 days post insemination
-Finds DG29 marker – a proprietary “Pregnancy Specific Protein”

-Cattle, sheep, goats

Question 12

what are some potential hormone tests for pregnancy diagnosis

Answer 12

Species Dependent
-Progesterone
-Estrogens
-Equine Chorionic Gonadotropin
-Progestagens
-Relaxin

Question 13

hormonal pregnancy diagnosis in cows
-what hormone
-time of low/high values
-can this confirm pregnancy

Answer 13

-Progesterone

-Low levels 19 – 21 days post breeding are suggestive of estrus and NON pregnancy

High levels do not confirm pregnancy
-Cannot differentiate from Diestrus
-Pyometra, mummified fetus etc.
-Progesterone is NOT a good pregnancy test

Question 14

Hormonal analysis in mares – potential tests

Answer 14

-Progesterone
-Equine Chorionic Gonadotropin (eCG)
-Estrone Sulfate

Question 15

Hormonal analysis in mares – eCG
-when can you use
-false negatives
-false positives
-what can you use with this

Answer 15

-Test between 40 and 120 days
-Cups persist through 120 days even
if fetus dies = false positives

False negatives = tails of curve
-Too early in pregnancy
-Too late – after cups are gone
-Can use together with estrone sulfate – tandem assay repeated after 2-4 wks

-If show rising levels of estrone, with continued presence of eCG, indicates live fetus, viable pregnancy

Question 16

Hormonal analysis in mares; estrogens
-when to use
-diagnosis

Answer 16

Estrone sulfate (conjugated estrogen):
-Serum estrogens elevated as soon as Day 35-40
-After Day 60 feto-placental source

-Diagnostic of pregnancy by day 45 >6.0 ng/ml (BEWARE THE MINI: day 80 >60.0 ng/ml)

-Can be used for fetal viability prior to 7 months gestation

Question 17

Hormonal analysis in the bitch
-what hormone is useful
-what is it produced by and when

Answer 17

-Progesterone is NOT useful (same diestrus phase whether pregnant or not)
-Relaxin hormone (Witness® or ReproCheck®)
-Produced by canine placenta; increases in pregnancy, NOT diestrus
-From days 22-27 after breeding

Question 18

Pregnancy diagnosis in cows by palpation; what are the 4 absolute signs?

Answer 18

The four absolute (definite) signs on rectal palpation:
-Amniotic vesicle
-Fetal membrane slip
-Fetus
-Placentomes

Question 19

Palpation of the uterus – estimation of gestational age in cows (fluid and size of fetus)

Answer 19

Fluid
-Horn diameter
-Day 30 – 1 in. diameter
-Day 60 – 3 in. diameter
-Day 90 – 6 in. diameter

Size of fetus
-Day 60 – large mouse
-Day 90 – rat
-Day 120 – cat

Question 20

Palpation of the uterus – timing of events in the cow – First felt

Answer 20

Fluid-filled horn (CL on same side)
-Heifers: d 30
-Cows: d 30-40

-Fetal membrane slip: > d 30
-Ballot Fetus: > d 70
-Feel Placentomes: > d 80-90

Uterine artery “fremitus:” > d 80-120
-“buzzing” of the middle uterine artery within broad lig.
-Apply slight pressure to artery to feel
-Associate with pregnancy but not definitive

Question 21

Differential diagnoses for pregnancy - rectal palpation (6)

Answer 21

Other causes for uterus not retractable
-Adhesions, large ovarian tumour

Other causes of fluid in the uterus
-Pyometra
-Mucometra

Other causes of masses in the uterus
-Mummified or macerated fetus
-Tumor

-Embryonic death

-Incomplete postpartum involution

-Palpation of the bladder

Question 22

Palpation of the uterus - mares

-what do you feel and when

Answer 22

Increase in cervical and uterine tone
-Usually by day 15-18

Detect bulge at the base of uterine horn
-Ventral aspect
-By day 20-25

Ballot fetus
-Day 90-120

Question 23

Palpation of the uterus - bitch

Answer 23

-Abdominal palpation is reliable and safe between 25-30 days
-At this stage individual sacs can be palpated

Question 24

Ultrasonography -Earliest day detectible
-cows
-equine
-small ruminants
-porcine
-canine
-feline

Answer 24

-Bovine: approx day 27 (Placentomes first visible on U/S by day 35-40)

-Equine: day 10 (day 14 is typical)

Small ruminants:
-Transrectal: day 18
-Transabdominal: day 35

-Porcine: transabdominal, from day 22

-Canine: day 18 from OV

-Feline: day 16 from OV

Question 25

when are placentomes first seen in cows

Answer 25

30-35 days

Question 26

when can ultrasound detect pregnancy in mares

Answer 26

-In the mare pregnancy can be identified as early as 10 days post-ovulation by ultrasound
-Day 14 is the usual first check

Question 27

use of doppler ultrasonography

Answer 27

-Highlights blood flow
-Earlier diagnosis
-Fetal heartbeat

Question 28

Small ruminants ultrasound
-what do you have to differienate from pregnancy

Answer 28

-Ultrasound is useful to differentiate pregnancy from hydrometra (false pregnancy) of goats
-Fluid but absence of placentomes, no fetus

Question 29

Ultrasound exam - bitch
-when to use and for what

Answer 29

-Transabdominal
-As early as day 20
-Estimation of fetal numbers
-Fetal viability
-Gestational age
-Predict whelping dates

Question 30

Ultrasound diagnosis of fetal gender
-when
-how to tell the difference

Answer 30

-Day 60 is ideal in cattle and mares for transrectal
-Examine the area under the tail (female) and behind umbilicus (male) for genital tubercle
-Later examinations > 90 days to look for gonads

Question 31

Ultrasound in later pregnancy
-what you look at

Answer 31

-Fetal age

Fetal health
-Heart rate
-Activity
-Placenta

-Twins

Question 32

what 4 methods of pregnancy and most useful

Answer 32

-Blood tests for “pregnancy factors”
-Hormonal analysis
-Palpation of the uterus
-Ultrasonography of the uterus