pregnancy diagnosis · why pregnancy check? •avoid feeding cost through the winter that will not...

Pregnancy diagnosis

17/10/2019

Why pregnancy check?

• Avoid feeding cost through the winter that will not produce a calf.

– cost of stored feed is a high percentage of input.

– maintaining an open cow for Midwest is ~$320/year.

• Cull cow costs are higher in September than November….so preg check earlier if possible.

(In general, the better you are, the earlier you can pregcheck)

• Improve pregnancy rate of your herd by eliminating infertile females……

• Know expected calving dates of females:

– For herd records and labor management

– To sell bred replacement heifers to match a buyer’s calving season

• Pregnancy determination can also help you manage feeding to meet the high nutritional demands of gestation, calving, lactation and rebreeding more effectively.

Why pregnancy check?

1: Vulva; 2: Vagina; 3: Cervix; 4: Body of the uterus; 5: Right uterine horn; 6: Oviduct; 7: Ovary; 8: Urinary bladder; 9: Ischial bone (cut); 10: Rectum.

Characteristics of non-pregnant reproductive tract

Methods of pregnancy diagnosis

• Visual methods– Non-return to estrus

– Cocking of the tail (dromedary camel): 14 to 15 days after fertile mating

• Clinical methods– Recto-genital palpation: cost effective

– Abdominal ballottement

– Ultrasonography

– Radiology

– Blood Test for Pregnancy Specific Protein B

Recto-genital palpation

• Basic principle• Restraint and clothing

– coveralls, gum boots and disposable plastic or rubber full arm sleeves

• Precautions during rectal palpation– Ruthless movements should be avoided– trim nails and avoid dirty soiled sleeves– sleeve must be used– Gently rectal palpation during fever– Care should the taken for preventing making fistula– Clinicians must assure that even it the animal kicks it

does not harm them– Uncareful palpation of the uterine horns with undue

pressure can cause rupture of the amniotic vesicle

• Consequences of improper palpation: termination of pregnancy

• Palpable findings of pregnancy in cattle and buffaloes: re-submitted for examination 15-30 days later preferably after a fasting.

• Location of pregnant uterus

– descending into the abdominal cavity: 3½ - 4 months

– abdominal floor: 4½ - 5 months

• during the 4 – 6½ months period and diagnosis has to be dependent on other features of pregnancy (placentomes or fremitus).

Recto-genital palpation

PREGNANCY DIAGNOSIS IN COW

• Palpation at 35 to 40 days:

– Uterus on the floor of the pelvis, except in large cows with elongated reproductive tracts.

– Slight enlargement of one horn with detectable dorsal bulging

– Palpation of corpus luteum on the ovary adjacent to gravid horn


• Palpation at 45 to 50 days

• Foetal membrane slip

• Uterus still on pelvic floor. Slightly greaterdifference in size

• Palpation of corpus luteum on the ovary adjacentto gravid horn.

Gravid uterus at ~60 days

• The gravid uterinehorn will be droppingslightly over the brimof the pelvis andfeels like balloonfilled water

• Corpus luteum onthe ovary adjacent togravid horn

• Fetal membrane slip

Gravid uterus at 90 days• The uterus will be

pulled well over thepelvic brim and willbe 8 to 10 cm indiameter

• The foetus will be 10to 15 cm long andeasily palpated.

• Corpus luteum onthe ovary adjacent togravid horn.

• enlargement of theuterine arteries withtheir characteristicpulsation.

End of third month

Gravid uterus at ~110 days• The uterus will be well

over the brim of thepelvis with the cervixpulled almost to thepelvic brim.

• The foetus can be easilypalpated and will be from25 to 30 cm long.

• Small palcentomes canbe identified

• The ovaries may bedifficult to reach, but a CLwill be present on theovary adjacent to thegravid horn.

Fifth month of gestation• The uterus will be

pulled well into theabdominal cavity andthe cervix will belocated at the brim ofthe pelvis

• Distinct placentomesabout the size ofovaries can beidentified

• The foetus is wellformed and will be 35to 40cm in length butmay be difficult toreach in larger cows

The pulse of pregnancy (fremitus) will be quite distinct with the artery being 6 mm to 1.25 cm in diameter

Sixth month of gestation• Cervix will be at the brim

of the pelvis and may bebent over the edge.

• The dorsal wall of theuterus will be tight anddifficult to palpate.

• The placentomes willvary in size and may bedifficult to palpate

• The foetus will be difficultto palpate particularly inlarger cows due to thedepth of the abdominalcavity.

•There will be strong pulseof pregnancy (fremitus) andthe artery will be 1.25 to 1.4cm in diameter.

Palpation at 230 days to 280 days: (7.5 to 9 months)

•The foetus will be large enough toextend back within range of thehand. The head and front feet areusually the structures palpated.

•Movement of the foetus canfrequently be detected.


Pregnancy diagnosis by rectal palpation remains one of themost practical means for detecting pregnancy in cattle:

Structures to be palpatedCervix:

The cervix is chiefly a landmark serving as a guide for locatingother structures.

The position of cervix can give an indication of the stage ofpregnancy, but a diagnosis should never be based on the cervixalone.


Uterus:

The uterine wall becomes thinner as pregnancyprogresses and is very resilient to touch compared withthe uterus of the open cow.

The thickness and tone of the uterine wall areimportant.

The size of the uterus (asymmetry) influences itsposition in relation to the pelvis and should be noted.

Most of the diagnosis is based on the uterus and itscontents.


Foetal membrane Slip:

By 120 days (4 months) the placentomes are largeenough to palpate through the uterine wall.

Therefore, the term “slipping of the foetal membrane”has been used to describe this procedure.

With some practice one can feel the membrane slip frombetween the thumb and finger.

Gently grasping the uterine wall between the thumb andforefinger and lifting slightly can detect the chorionicmembrane.

PREGNANCY DIAGNOSIS IN COW• The contents of the uterus

are the most positivediagnostic structures to bepalpated.

• After 90 days, the foetus canbe palpated except during aperiod from 170-230 days(6-7 months) when it is toodeep in the abdominal cavityto reach in large cows.


Amniotic Vesicle:

The vesicle is turgid early in pregnancy but becomesflaccid with advancing pregnancy until days 65 to 70when it is difficult to detect at all

From approximately 30 to 65 days gestation, theamniotic vesicle can be detected as a movable ovalobject within the uterine lumen..


Parameter Size Gestation age.

Amniotic 1 (finger width) 1.5cm 42 (days)vesicle 2“ 3.5 cm 48 (days)

3“ 5.5 cm 52 (days)4“ 7.5 cm 58 (days)4 **“ 9.0 cm 62 (days)5“ 10.5 cm 65 (days)


Placentomes:

In general, they can be detected as soft, thickenedlumps in the uterine wall and are more easily detachedas pregnancy advances.

Since there is great variation in size among individualplacentomes, usefulness in aging a pregnancy islimited.

The presence of placentomes is another positive signof pregnancy and is detectable from about 75 days toterm.

fetus - simple enough! Cotyledons/caruncles

Placentomes (cotyledons on the placenta/caruncles on the uterus)

Placentome size


Depending on the skill of the examiner and thelocation of the foetus, the foetus can be palpatedfrom the time of amniotic softening (65 to 70days) to term.

Of course, the presence of the foetus itself is asign of pregnancy.

Palpation of the Foetus:

Foetal growth is quite uniform up to about thesixth month, so that foetal size can be used toestimate foetal age accurately.


Parameter Fetal Size Fetal Head size Gestation ageFoetus Mouse Marble 2 months

Rat Golf ball 3 monthsSmall cat Tennis ball 4 monthsLarge cat Softball 5 monthsBeagle dog Beagle dog 6 months

Fremitus Unilateral 120+ daysin uterine Bilateral 210+ daysartery


• Ovaries

• The ovaries can be palpated upto about 120 days.

• Structures on the ovary canhelp confirm either a positive ora negative diagnosis.

• Pregnancy is alwaysaccompanied by CL

• However, one must rememberthat a CL is not alwaysaccompanied by pregnancy.


• Pulse of pregnancy (thrill” or“Fremitus)• Helpful in confirming a diagnosis

and also confirming the viability ofcalf, particularly at certain stages ofpregnancy

• Felt in the middle uterine artery,which supplies blood to foetus

• By 120 days of pregnancy themiddle uterine artery will haveenlarged sufficiently to be used as adifferential diagnosis in pregnancydetermination by rectal palpation.


• Pulse of pregnancy (thrill” or “Fremitus)

• Enlargement of the uterine arteryipsilateral to the pregnant horn isdetectable after 80 to 90 days of gestation

• By approximately 130 days, the blood flowwithin the ipsilateral uterine artery hasincreased to the point at which turbulenceis palpable as a buzzing sensation, alsoreferred to as a thrill or fremitus.


Diameter of pregnant bovine uterine horn atdifferent stages of pregnancy:

•Stage in days Diameter (cm)

30 Slight enlargement &

dorsal bulging

60 7

90 8

120 12

150 18

Approximate volumetric measurement of uterine horn

Days of gestation Volume of uterine horn

30 days 30-60 ML

40 days 75-100ML

50 days 90-200ML

60 days 200-450ML

70 days 350-650MlL

Abdominal ballottement

• In cattle abdominal ballottement is performed by placing the first over the lower right abdominal wall and pushing it in an intermittent manner in a dorsal medial direction deeply. The fetus can be felt as a hard solid object floating in fluid. This is usually possible in lean cows after the 7th month of gestation– Cow: 7 month onward

– Sheep and goat: 4 month

Ultrasond method• There are different types of

machines available. The most commonly used machines today are B-mode real-time, meaning that they produce an acoustic image in real time.

• They usually range from 3.5 -7.5 MHz. With greater MHz you see more detail but have less depth penetration

• There is more depth penetration with lower MHz, but less detail.

Ultrasond method

Fetal echocardiography

• limited extent fetal echocardiography

• Vaginal electrical resistance

– conductivity of the vaginal mucous membranes changes at estrus due to increased hydration, increased blood supply and other changes.

– vaginal electrical resistance (VER) is low at estrus

• Laparoscopy: directly visualizing the genitalia

in animals but costly

• Laboratory tests– Progesterone hormone assay– Estrone sulfate– Chemical tests for pregnancy diagnosis: cuboni test– Assay of gonadotrophins– Biologic test: detection of eCG including the Aschiem

Zondek Test, the Friedman test (rabbit test) or the Frog or toad test. Aschiem Zondek test

• On farm tests• Milk ejection by low dose prostaglandin• Pregnancy associated glycoproteins (PAG)• Early pregnancy factor

Methods of pregnancy diagnosis (indirect method)

Laboratory test (indirect method)• Progesterone hormone assay

– Low progesterone concentrations in maternal blood at 18 to 24 days post breeding can predict that the animal is non-pregnant and vice versa

– Available ELISA, plasma or milk progesterone assay kits have not become popular due to their high cost and a low specificity

• Estrone sulfate – Estrone sulfate is produced by the feto-maternal axis or

the conceptus and therefore its presence in urine, milk, feces or blood is an indicator of pregnancy.

– 120 days of gestation and specially suggested for miniature horses and donkeys

– RIA, EIA

• Cuboni test:

– A positive (pregnant) test is indicated by the appearance of a dark, only green fluorescent color in the lower sulfuric acid layer and

– A negative (non-pregnant) is characterized by absence of fluorescent color and presence of a brownish color

• Effective beyond 150 days of gestation, 70-80% accurate

Laboratory test (indirect method)

• Barium chloride test– In non-pregnant cows a white precipitate is

formed, whereas, in pregnant animals the urine remains clear

– The accuracy of the test was described to be 70-95%, from 15 to 210 days of pregnancy

• Milk alchohol coagulation test

• Copper sulfate test

• Costa’s test

• Kosjakovs test

Laboratory test (indirect method)

Pregnancy associated glycoproteins(PAG)

• Two pregnancy specific proteins (PSP) A and B have been isolated from bovine fetal membrane extracts . Of these PSP-A was identified as a a-fetoprotein and PSP-B was found to be specific to the placenta.

• Cattle , buffalo, sheep and goats and accuracy from 29 to 30 days post breeding

• The sensitivity and specificity of PSP-B based on RIA is known to be 92.0% and 82.6 to 91.9% from 29 to 30 days post insemination

• ELISA

Early pregnancy factor (EPF)

• Rosette inhibition bioassay

• EPF was detected in the serum of all mammals tested within 24 to 48 h of fertilization and disappeared within 24 to 48 h after death or removal of embryo

• Mice, sheep and cattle

Relaxin assay

• Relaxin is produced by the placenta in the bitch and cat

• Peripheral circulation of pregnant bitches at 20-30 days of gestation, whereas it is absent in non-pregnant bitches at all stages of the reproductive cycle.

Vaginal Biopsy

• The basis for the test is the decrease in the layers of the stratum germinativum under the influence of progesterone.

• The number of layers is high at estrus (around 20 layers) due to influence of estrogen hormone.

• The accuracy of this method between 18 and 22 days is 97% and 94% for the diagnosis of pregnancy and non-pregnancy respectively in the sow

Determination of fetal age

Definite signs of pregnancy(pregnancy specific)

• Palpation of enlarged uterine horn containing the placental fluids

• Palpation of the amniotic vesicle

• Slipping of the fetal membranes

• Palpation or ballottement of the fetus

• Palpation of the placentomes

• Palpation of enlarged thin walled “whirring” uterine arteries– To confirm <60 day pregnancy

Things that are NOT pregnancy-specific but can assist in your diagnosis

• 1. Fluid in one or both horns WITH a thin-walled uterus

• 2. Fremitus = ?

– the ‘buzz’ felt when palpate hypertrophy of the middle uterine artery

• 3. Can’t retract tract up onto rim with cervix

• 4. Corpus luteum – which ovary?

False positives(You said she’d calve, but she never does.......

How differentiate?

1. Bladder – fluid-filled No slip, no fetus, ribbed feel to bladder wall

2. Pouch of the rumen Fibrous feel, you can indent it with a finger

3. Cow’s right kidney Location is always high and right, moves very little

4. Postpartum tract Will feel caruncles, but no calf… Good RECORDS!

5. Repro tract abnormality

Is it IN the uterus?

pregnancy diagnosis · why pregnancy check? •avoid feeding cost through the winter that will not...

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