Pregnancy Pregnancy DeterminationDetermination

Pregnancy DeterminationPregnancy Determination

AdvantagesAdvantages Increase herd productivityIncrease herd productivity Cull non-pregnant femalesCull non-pregnant females Rebreed non-pregnant femalesRebreed non-pregnant females Separation of twins vs. singles (ewes)Separation of twins vs. singles (ewes)

**If done properly there are not many **If done properly there are not many disadvantagesdisadvantages

Pregnancy DeterminationPregnancy Determination

A pregnancy test A pregnancy test mustmust be: be:

QuickQuick InexpensiveInexpensive SimpleSimple AccurateAccurate Minimize animal handling and laborMinimize animal handling and labor Cannot cause abortionCannot cause abortion

Determining age by uterine Determining age by uterine characteristics and fetal sizecharacteristics and fetal size

Days of Days of GestatioGestationn

Identifying CharacteristicsIdentifying Characteristics Relative Relative Fetal SizeFetal Size

3030 *Uterus in approximate position of *Uterus in approximate position of nonpregnant uterusnonpregnant uterus

*One uterine horn slightly *One uterine horn slightly enlarged and thinning uterine wallenlarged and thinning uterine wall

*Fetal membranes may be slipped *Fetal membranes may be slipped through fingers from 30-90through fingers from 30-90

Small Small MarbleMarble

(1/100 oz.)(1/100 oz.)

4545 *Uterine horn somewhat enlarged, *Uterine horn somewhat enlarged, thinner walled and prominentthinner walled and prominent

Small EggSmall Egg

(1/8-1/4 (1/8-1/4 oz.)oz.)

6060 *Uterine horn 2 *Uterine horn 2 1/21/2 to 3 to 3 1/21/2 in in diameterdiameter

*Uterine horn is fluid filled*Uterine horn is fluid filled

MouseMouse

(1/4-1/2 (1/4-1/2 oz.)oz.)

Days of Days of GestatioGestationn

Identifying CharacteristicsIdentifying Characteristics Relative Relative Fetal Fetal SizeSize

9090 *Both uterine horns swollen (4-5” diameter)*Both uterine horns swollen (4-5” diameter)

*Uterus begins descending into abdominal *Uterus begins descending into abdominal cavitycavity

*Uterine artery *Uterine artery 1/81/8 to to 3/163/16” in diameter” in diameter

*Cotyledons ¾ to 1” across, very soft*Cotyledons ¾ to 1” across, very soft

RatRat

(3-6 oz.)(3-6 oz.)

120120 *Uterine horns continue descent into *Uterine horns continue descent into abdominal cavityabdominal cavity

*Uterine horns are 5 to 7” in diameter*Uterine horns are 5 to 7” in diameter

*Uterine artery ¼” diameter*Uterine artery ¼” diameter

*Cotyledons 1 ½ “ in length (more distinct)*Cotyledons 1 ½ “ in length (more distinct)

Small CatSmall Cat

(1-2 lb.)(1-2 lb.)

150150 *Difficult to palpate fetus*Difficult to palpate fetus

*Uterine horns are deep within body cavity*Uterine horns are deep within body cavity

*Uterine horns 6 to 8” in diameter*Uterine horns 6 to 8” in diameter

*Uterine artery ¼ to 3/8” diameter*Uterine artery ¼ to 3/8” diameter

*Cotyledons 2 to 2 ½ “ diameter*Cotyledons 2 to 2 ½ “ diameter

Large CatLarge Cat

(4-6 lb.)(4-6 lb.)

Days of Days of GestatioGestationn

Identifying Identifying CharacteristicsCharacteristics

Relative Relative Fetal Fetal SizeSize

180180 *Uterine horns are deep within the *Uterine horns are deep within the abdominal cavity and ascending phase abdominal cavity and ascending phase of growth beginsof growth begins

*Uterine artery 3/8 to ½ “ diameter*Uterine artery 3/8 to ½ “ diameter

*Cotyledons are more enlarged*Cotyledons are more enlarged

*From 6 months until calving the feet, *From 6 months until calving the feet, legs, or head of the fetus can be easily legs, or head of the fetus can be easily palpatedpalpated

Small DogSmall Dog

(10-16 lb)(10-16 lb)

After 7 After 7 monthsmonths

*Uterine artery ½ “ diameter at 210 *Uterine artery ½ “ diameter at 210 daysdays

*Uterine artery ½ to 5/8” diameter at *Uterine artery ½ to 5/8” diameter at 240 days240 days

*Uterine artery ½ to ¾” diameter at *Uterine artery ½ to ¾” diameter at 270 days270 days

*Continued increase in cotyledons *Continued increase in cotyledons after 7 monthsafter 7 months

210 (20-30 lb)210 (20-30 lb)

240 (40-60 lb)240 (40-60 lb)

270 (60-100 270 (60-100 lb)lb)

Increasing Increasing Fetal SizeFetal Size

Determining the Stage of Pregnancy Determining the Stage of Pregnancy

Open cowsOpen cows: In females that are nonpregnant, the : In females that are nonpregnant, the reproductive tract is usually located within the reproductive tract is usually located within the pelvic cavity; however, in older and large-pelvic cavity; however, in older and large-frame cows the cervix and uterine horns may frame cows the cervix and uterine horns may be distended over the pelvic brim into the be distended over the pelvic brim into the body cavity.body cavity.

Determining Factors:Determining Factors:1.1. No fluids in uterusNo fluids in uterus2.2. No membranes present upon slippageNo membranes present upon slippage3.3. Thick uterine wall with a meaty textureThick uterine wall with a meaty texture4.4. Uterine tone:Uterine tone:

Firm – at or near estrusFirm – at or near estrusFlaccid – between estrus periodsFlaccid – between estrus periods

Determining Stage of Determining Stage of PregnancyPregnancy

Pregnancy Stage 1Pregnancy Stage 1: Females in this stage : Females in this stage vary from 40 days to 3 months of vary from 40 days to 3 months of pregnancy. Cervix and uterine horns pregnancy. Cervix and uterine horns are in the pelvic cavity or perhaps are in the pelvic cavity or perhaps moving over the pelvic brim in to the moving over the pelvic brim in to the body cavity as stage 1 advances.body cavity as stage 1 advances.

Determining factors:Determining factors:1.1. Fluids in uterus and somewhat enlargedFluids in uterus and somewhat enlarged

2.2. Presence of membranes upon slippagePresence of membranes upon slippage

3.3. Thin uterine wallsThin uterine walls

4.4. Buttons indistinct to the touchButtons indistinct to the touch

Determining Stage of Determining Stage of PregnancyPregnancy

Pregnancy Stage 2Pregnancy Stage 2: Females in this stage : Females in this stage vary from 3 to 5 ½ months of pregnancy. vary from 3 to 5 ½ months of pregnancy. Cervix is normally located on the pelvic Cervix is normally located on the pelvic brim with uterine horns distended into the brim with uterine horns distended into the body cavity out of the normal reach.body cavity out of the normal reach.

Determining Factors:Determining Factors:

1.1. Displacement of the uterusDisplacement of the uterus2.2. Presence of buttonsPresence of buttons3.3. Pulsation of middle uterine arteryPulsation of middle uterine artery

Fremitis – palpation of the uterine arteryFremitis – palpation of the uterine artery

Determining Stage of Determining Stage of PregnancyPregnancy

Pregnancy Stage 3Pregnancy Stage 3: Females in this stage : Females in this stage vary from 5 ½ months pregnant to term. vary from 5 ½ months pregnant to term. Cervix is at or near the pelvic brim. Cervix is at or near the pelvic brim. Developing calf has achieved sufficient Developing calf has achieved sufficient size to be reached. Palpation of the calf size to be reached. Palpation of the calf becomes progressively easier as Stage 3 becomes progressively easier as Stage 3 advances.advances.

Determining factors:Determining factors:1.1. Displacement of uterusDisplacement of uterus2.2. Palpation of large fetusPalpation of large fetus3.3. Presence of buttonsPresence of buttons