Laboratory of Animal Endocrinology and Reproduction

Liège, Belgium

Laboratory of Animal Endocrinology and Reproduction

Liège, Belgium
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Szenci O.,Clinic for Large Animals | Karen A.,Clinic for Large Animals | Karen A.,Kafr El Sheikh University | Bajcsy A.C.S.,Clinic for Large Animals | And 2 more authors.
Theriogenology | Year: 2011

The aim of the present study was to evaluate the effect of restraint stress, which is commonly practised in the field, on plasma concentrations of cortisol, progesterone (P4) and bovine pregnancy-associated glycoprotein-1 (boPAG-1) in pregnant heifers between Days 30 to 40 of gestation. Twelve Holstein-Friesian heifers between Days 30 (Day 0 of experiment) and 40 (Day 10 of experiment) of pregnancy in a Hungarian dairy farm were used in the present study. The heifers were exposed to an acute stressor consisting of immobilisation (restraint stress) in a crush for 2 h (Group 1, n = 6) on Day 2 (Hour 48) and for 2 × 2 h (Group 2, n = 6) on Days 2 and 3 (Hour 72) of the experiment. Transrectal ultrasonography (7.5 MHz linear-array rectal transducer) was performed daily from Day 0 to Day 10 of the experiment to detect embryonic heartbeat or the fate of the conceptus. Blood samples were withdrawn before each ultrasonographic examination. Additional blood samples were withdrawn by 1 and 2 h (at Hours 49 and 50 in Groups 1 and 2 and Hours 73 and 74 in Group 2) of the onset of applying the stressor. Plasma cortisol, P4 and boPAG-1 concentrations were measured by radioimmunoassay. Acute restraint stress significantly (P < 0.001) increased the plasma cortisol level in pregnant heifers at 1 h of the exposure to the stressor at Days 2 (48 h) and 3 (72 h) of the experiment. On the other hand, the restraint stress did not affect the concentration of P4 and boPAG-1 concentrations in both groups. In conclusion, restraint stress for 2 h during early pregnancy in heifers increased blood cortisol, but it did not affect the concentrations of P4 and boPAG-1 between Days 30 to 40 of gestation. © 2011 Elsevier Inc.


Karen A.M.,Kafr El Sheikh University | Darwish S.,Egyptian Animal Production Research Institute | Ramoun A.,Kafr El Sheikh University | Tawfeek K.,Egyptian Animal Production Research Institute | And 5 more authors.
Tropical Animal Health and Production | Year: 2011

The present study was undertaken to evaluate the accuracy of transrectal palpation (TRP) for diagnosing early pregnancy in buffaloes and the false diagnoses of the TRP test by using the pregnancy-associated glycoprotein radioimmunoassay (PAG-RIA) test. Pregnancy was diagnosed in 168 buffalo-cows once by TRP and PAG-RIA test between days 31 and 55 after breeding. The sensitivity of TRP for detecting pregnant buffalo-cows was 37. 5% at days 31-35, increased to 93. 8% at days 46-50 and reached 100% at days 51-55 (P < 0.01). All cases of false negative diagnoses (n = 10) had PAG concentration higher than the threshold (≥1.8 ng/mL) for diagnosing pregnancy. The specificity of TRP for detecting non-pregnant buffalo cows ranged between 90.9%, and 100% between days 31 and 55. All cases of false positive diagnoses (n = 5) made by TRP had PAG concentrations lower than the threshold for diagnosing pregnancy. It could be concluded that TRP is an accurate method for diagnosing pregnant and non-pregnant buffalo cows from day 46 after breeding. © 2010 Springer Science+Business Media B.V.


Karen A.,MTA SZIE Large Animal Clinical Research Group | Karen A.,Kafr El Sheikh University | Bajcsy A.C.,MTA SZIE Large Animal Clinical Research Group | Minoia R.,University of Bari | And 6 more authors.
Journal of Reproduction and Development | Year: 2014

The aim of the present study was to determine the relationship of progesterone (P4), bovine pregnancy-associated glycoprotein-1 (bPAG-1) and nitric oxide (NO) levels with late embryonic (LEM; day 28 to day 42) and early fetal mortalities (EFM; > day 42 to day 56) in dairy cows. Transrectal ultrasonography (6-8 MHz) was performed in 100 Holstein-Friesian cows at days 28, 42 and 56 after artificial insemination (AI; day 0) to diagnose pregnancy and to monitor the fate of the embryo. After ultrasound scanning of each cow, a milk sample was collected for assessment of P4 by an ELISA test and a blood sample was collected for assessment of bPAG-1, by using a double-antibody radioimmunoassay, and serum NO metabolites (nitrate + nitrite). Based on ultrasonographic examinations and bPAG-1-RIA, 41 of 100 inseminated cows were confirmed pregnant at day 28 after AI. Nine cows suffered of LEM, and 6 cows suffered of EFM and the overall pregnancy loss rate was 36.6% (15/41) between days 28 and 56 of pregnancy. By logistic regression analysis, there were no significant relationships between the level of P4 and bPAG-1 at day 28 after AI and the occurrence of LEM and EFM. Also, there were no significant relationships between the levels of P4 and bPAG-1 at day 42 and the occurrence of EFM. On the other hand, a significant relationship (P<0.05) was found between NO level at day 28 and the occurrence of LEM. In conclusion, measurement of the serum NO concentration at day 28 of pregnancy might help to predict the outcome of pregnancy by day 42 in dairy cows but further studies are needed to confirm this. © 2014 by the Society for Reproduction and Development.


Shahin M.,University of Gottingen | Friedrich M.,University of Gottingen | Gauly M.,University of Gottingen | Beckers J.F.,Laboratory of Animal Endocrinology and Reproduction | Holtz W.,University of Gottingen
Small Ruminant Research | Year: 2013

Pregnancy-associated glycoproteins (PAGs) are macromolecules produced by placental tissue and released into the maternal circulation where they allow pregnancy diagnosis and follow-up. The present study addresses the question to what extent plasma PAG determination may serve as a means of early pregnancy detection in goats in a similar way it is practiced in cows, and whether an ovine or bovine PAG-ELISA may be utilized to this end. Blood samples were collected from eight pregnant pluriparous Boer goat does twice weekly during the first seven weeks and the last four weeks of pregnancy and weekly in-between and during four weeks following parturition. Plasma PAG concentrations (mean ± SEM) were determined using a competitive enzyme-linked immunosorbent assay. Assays were conducted with polyclonal antisera raised in rabbits against purified preparations of caprine (AS#706), ovine (AS#780) and bovine PAG (AS#726). In the assay systems purified bovine PAG served as standard and tracer and goat anti-rabbit IgG served as coating antibody. With the antibody raised against caprine PAG (AS#706) a steep increase to a climax of 69 ± 9. ng/ml on day 56 of pregnancy was followed by a gradual decline to 16 ± 3. ng/ml at parturition and 0.3 ± 0.07. ng/ml four weeks postpartum. The results achieved with the anti-ovine PAG (AS#780) showed close similarity, a maximum of 92 ± 14. ng/ml being reached at 56 days of pregnancy. With anti-bovine PAG (AS#726), the PAG level increased to a maximum of 3.1 ± 0.2. ng/ml on day 105 of pregnancy and fluctuated around 3. ng/ml until the end of pregnancy. The difference between pregnant and non-pregnant does reached a significant level 21 days after conception, one week earlier than with caprine and ovine antisera. © 2013 Elsevier B.V.

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