Pregnancy determination in cattle

Question 1

Types

Answer 1

Rectal examination of the uterus
Ultrasound
Biochemical tests

Question 2

Rectal examination of the uterus

Answer 2

Pregnancy check
• Fluctuation:
    o Fluid in the uterine lumen
    o Safe and precise on Day 35 to 70 
    o (US: from Day 25 (28) )
• Palpation of the amnion:
    o We palpate the amnion itself in the fluid-filled lumen 
    o Foetal mortality 
• Membrane slip:
    o we slip the foetal membranes between our fingers when palpating the 
    o fluid-filled uterine horn
    o Foetal mortality 

Question 3

Ultrasound

Answer 3

• Ultrasound transducer into rectum
o Linear probe: inserted into rectum with arm
o Convex probe: inserted into rectum with extension arm
▪ Can be difficult to detect pregnancies older than 6 months because foetus is deep in the cow and pulls uterus over the pelvis
• Easy to learn
• Can detect pregnancy as early as 25-30 days (experienced operator)
• 45 days: most people can accurately detect pregnancy
• Can determine viability of foetus, presence of multiple embryos, foetal age,
calving date and occasionally foetal defects
• Experience operator: can detect sex at 55-80 days

Question 4

Biochemical tests

Pregnancy-associated glycoproteins

Answer 4

• Proteins produced by the placenta of the developing calf that enter the maternal blood stream
• Can be detected approx. 25-30 days after breeding
• Can be detected for up to 60 days after calving

Question 5

Biochemical tests

Pregnancy associated glycoprotein subtypes : PAG

Answer 5

• Aspartate proteinase family members, proteolytic enzymes
• Cell specific expression
• Unknown function

Question 6

Biochemical tests

Pregnancy associated glycoprotein subtypes : PAG

bPAG-1

Answer 6

• Genetically younger cells produce
• Only binucleatee cells produce
• After day 25 of pregnancy proteins cross basement membrane and show up in maternal circulation
• Higher plasma concentration in crossed animals

Question 7

Biochemical tests

Pregnancy associated glycoprotein subtypes : PAG

bPAG-2

Answer 7

• Genetically older cells produce
• Mono and binucleate cells produce
• Cells are located mostly at the foetomaternal border of the placenta
• PAG 2 production start earlier and lasts longer in the placenta

Question 8

Biochemical tests

Pregnancy associated glycoprotein subtypes : PAG

On farm PAG measurement

Answer 8

• Rapid visual PAG test

* Sandwich type ELISA