Ultrasonographic appearance of the conceptus, fetal heart rate and profiles of pregnancy-associated glycoproteins (PAG) and prostaglandin F2alpha-metabolite (PGF2alpha-metabolite) after induction of fetal death with aglepristone during early gestation in cattle.
A higher incidence of fetal losses, especially after the use of artificial reproduction techniques, asks for more intensive monitoring of bovine pregnancies. In this study, a model for fetal death (FD) was created by administering the antiprogesterone aglepristone twice, at Day 47 and 48 of gestation (n=5). Control heifers received the solvent (n=5). The temporal relationships between changes in ultrasonographic appearance of fetal fluids and membranes, fetal heart rate (FHR) and peripheral plasma levels of pregnancy-associated glycoprotein (PAG) and PGF2alpha-metabolite as determined by radioimmunoassay associated with FD were monitored at eight hour intervals around treatment. For the analysis of plasma levels the period under study was divided into five epochs (T1: before injection of aglepristone/solvent; T2: from first to second injection; T3: from second injection to FD; T4: from diagnosis of FD to 56 h later; T5: from 56 h to 104 h after diagnosis of FD). Control heifers produced healthy calves at term, but in treated heifers, FD occurred on average at 58 (range 48-80) h after first injection of aglepristone. Fetal death was always preceded by a visible reduction of the amount of allantoic fluid and by segregation of the allantochorionic membrane from the endometrium. FHR remained rather constant in both groups, but a (non-significant) drop in FHR around 8h before FD was diagnosed in four of five treated animals. All fetuses were expulsed after FD. Levels of PAG remained constant or even slightly increased in controls, but decreased in treated animals from T2 onward: levels during T4 and T5 significantly differed from those during T1 and from values in controls during T4 and T5 (P<0.01). PGF2alpha-metabolite levels did not change in the controls, but in the treated group they were significantly higher during T3 when compared to T1 (P<0.05). After this increase, a sharp decrease in PGF2alpha-metabolite level occurred, reaching a significantly lower level at T5 when compared to control animals (P=0.01). It is concluded, that FD induced by aglepristone is preceded by ultrasonographic visible changes in fetal membranes and fluids and a rise in PGF2alpha-metabolite and is followed by a drop in PAG and PGF2alpha-metabolite.
Breukelman
Simone P
SP
Utrecht University, Faculty of Veterinary Medicine, Department of Farm Animal Health, Yalelaan 7, 3584 CL Utrecht, The Netherlands. s.p.breukelman@vet.uu.nl
Szenci
Otto
O
Beckers
Jean-Francois
JF
Kindahl
Hans
H
Mulder
Edu J H
EJ
Jonker
F Herman
FH
van der Weijden
Bert
B
Revy
Dénes
D
Pogany
Károly
K
Sulon
José
J
Némedi
István
I
Taverne
Marcel A M
MA
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology*; D015237:Dinoprost / Q000097:blood*; D004195:Disease Models, Animal; D004963:Estrenes / Q000008:administration & dosage; D005260:Female; D005313:Fetal Death / Q000139:chemically induced / Q000503:physiopathology / Q000662:veterinary*; D005865:Gestational Age; D006023:Glycoproteins / Q000097:blood; D006340:Heart Rate, Fetal; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000097:blood*; D016216:Ultrasonography, Prenatal / Q000662:veterinary*
D004963:Estrenes; D006023:Glycoproteins; D011257:Pregnancy Proteins; C419063:aglepristone; D015237:Dinoprost