Early pregnancy diagnosis in goats by determination of pregnancy-associated glycoprotein concentrations in plasma samples.
Different RIA systems available for measuring the concentrations of pregnancy-associated glycoproteins (PAGs) in dairy goats were compared in order to evaluate their accuracy in early pregnancy diagnosis. Plasma concentrations of PAGs were determined by 3 heterologous RIA systems with a bovine PAG standard and tracer in combination with antisera anti-ovine PAG (RIA 1), anti-caprine PAG55 + 62 (RIA 2), anti-caprine PAG55 + 59 (RIA 3), and by 2 homologous RIA systems that employed caprine PAG55 + 62 and caprine PAG55 + 59 and their specific antisera (RIAs 4 and 5, respectively). In all of the RIAs, the mean concentrations of PAGs were significantly higher (P < 0.01) in pregnant than in nonpregnant goats from Day 21 onwards after breeding. On Day 21, the accuracy rates of early pregnancy diagnoses were 56% (RIA 1), 96% (RIA 2), 99% (RIA 3), 95% (RIA 4) and 90% (RIA 5), whereas on Day 28 these rates were > 99% for RIAs 2, 3, 4 and 5. The RIAs for PAGs depend on proteins from the placenta being present in maternal plasma and require only a single sample of blood, to distinguish pregnant goats from those that fail to return to estrus for other reasons. The homologous and semi-heterologous assays are highly accurate as early as Day 21 of pregnancy.
González
F
F
Faculty of Veterinary, Las Palmas de Gran Canaria, Spain.
Sulon
J
J
Garbayo
J M
JM
Batista
M
M
Cabrera
F
F
Calero
P
P
Gracia
A
A
Beckers
J F
JF
D000818:Animals; D001947:Breeding; D002417:Cattle; D005260:Female; D006023:Glycoproteins / Q000097:blood; D006041:Goats; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000097:blood*; D011258:Pregnancy Tests / Q000379:methods / Q000662:veterinary*; D011863:Radioimmunoassay; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors
D006023:Glycoproteins; D011257:Pregnancy Proteins