References of "El Amiri, B"
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See detailCould Western blot analysis be an alternative to radio-immunoassay for sheep pregnancy associated glycoproteins measurements ?
El Amiri, B.; El Abbadi, N.; Benjelloun, B. et al

in Reproduction in Domestic Animals (2010, September 15), 45(Suppl 3), 65

This study prospected whether Western blot analysis could be an alternative to radio-immunoassay (RIA) for sheep pregnancy diagnosis. Blood samples were taken from Boujaâd ewes (n= 9) and Boujaâd x D’man ... [more ▼]

This study prospected whether Western blot analysis could be an alternative to radio-immunoassay (RIA) for sheep pregnancy diagnosis. Blood samples were taken from Boujaâd ewes (n= 9) and Boujaâd x D’man (BD) cross breed (n= 12). The pregnancy associated glycoproeins (PAGs) were weekly monitored in plasma during the whole gestation and the first month postpartum by two RIA systems (El Amiri et al., 2007, Reprod Domest Anim 42:257-62). The highly immunoreactive samples derived from PAG profiles were tested using Western blot based on the same antiserum used in RIA. Each week (from the 13th to the 19th week), two pools of plasma samples (4 ml each) were taken from single and multiple lambing ewes respectively. Samples were submitted to a protein extraction at neutral pH, followed by ammonium sulfate (A.S.) precipitation, dialysis, and lyophilization. The placental extract was used as a check. Results revealed that ewes with multiple lambs presented numerically higher PAG concentrations. In both RIA systems, the high concentrations were recoded around the 19th week of gestation and the maximal concentrations varied from 120 to 700 ng/ml. In Western blot, the placental extracts reacted positively while the plasma samples did not give any positive reaction. In conclusion, the RIA remains the only sensitive method to measure PAGs in plasma. The present study strengthens the need to develop an ELISA kit as an alternative to RIA systems. [less ▲]

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See detailPregnancy-associated glycoprotein secretion in North Moroccan goats
Chentouf, M.; El Amiri, B.; Sulon, Joseph ULg et al

in Reproduction in Domestic Animals (2008), 43(6), 696-700

The plasma profile of pregnancy-associated glycoprotein (PAG) and its relationship with fetal number were studied in 14 North Moroccan goats using a semi-heterologous radioimmunoassay (RIA). Peripheral ... [more ▼]

The plasma profile of pregnancy-associated glycoprotein (PAG) and its relationship with fetal number were studied in 14 North Moroccan goats using a semi-heterologous radioimmunoassay (RIA). Peripheral blood was collected every day during the first month of pregnancy, afterward the blood samples were collected trice a week. The PAG were first detected at day 20 of pregnancy, their levels increase to week 8 of gestation then decrease slightly until parturition. Statistical differences between goats carrying one or two foetuses are observed from week 5 of pregnancy until parturition. Factorial Discriminant Analysis provides mathematical models for the discrimination between the litter size using the PAG level and the week of pregnancy. Using only one blood sample per week, high sensitivity, specificity and overall accuracy (74%, 88% and 81%) were obtained using these models. It is concluded that the PAG RIA is an effective tool for early diagnosis of pregnancy and for discrimination between the litter sizes in North Moroccan goats. [less ▲]

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See detailMeasurement of ovine pregnancy-associated glycoprotein (PAG) during early pregnancy in Lacaune sheep
El Amiri, B.; Karen, A.; Sulon, Joseph ULg et al

in Reproduction in Domestic Animals (2007), 42(3), 257-262

This study describes ovine pregnancy-associated glycoprotein (ovPAG) concentrations in 20 Lacaune sheep during early pregnancy. Measurements were performed by using semi-purified ovPAG as standard, tracer ... [more ▼]

This study describes ovine pregnancy-associated glycoprotein (ovPAG) concentrations in 20 Lacaune sheep during early pregnancy. Measurements were performed by using semi-purified ovPAG as standard, tracer and immunogens for antibody production in rabbits. Antisera R780 (against ovPAG(57+59kDa)) and R805 (against ovPAG5(58+61kDa)) were used respectively in RIA-780 and RIA-805. Blood samples were collected at days 0, 18, 20, 22 and 25 after artificial insemination. From day 18 after breeding onward, the mean ovPAG concentration was significantly higher (p < 0.001) in plasma samples from pregnant ewes (n = 17) than in non-pregnant ones (n = 3). The specific activity of the tracer was 11 760 Ci/mmol in RIA-780 and 14 900 Ci/mmol in RIA-805. The minimal detection limits for RIA-780 and RIA-805 were 0.2 ng/ml and 0.3 ng/ml, respectively. The intra-assay CV of samples with low (1.0 ng/ml), medium (2.5 ng/ml) and high (4.0 ng/ml) PAG concentrations were 3%, 6% and 9% for RIA-780 and 8%, 9% and 5% for RIA-805. The inter-assay CV in the same samples were 13%, 12% and 7% for RIA-780 and 13%, 11% and 5% for RIA-805. The recovery was higher than 95% in both assays. No cross-reaction was observed with members of aspartic proteinase family as well as with other tested proteins. In both RIA-780 and RIA-805, inhibition of the binding of the tracer by antisera was parallel between standard curve and serial dilutions of pregnant ewe samples. In conclusion, the two homologous RIA systems are suitable for early quantification of ovPAG concentrations in ewe plasma samples from day 18 after breeding. [less ▲]

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See detailComparison of accuracy of transabdominal ultrasonography, progesterone and pregnancy-associated glycoproteins tests for discrimination between single and multiple pregnancy in sheep
Karen, A.; El Amiri, B.; Beckers, Jean-François ULg et al

in Theriogenology (2006), 66(2), 314-322

The aim of the present study was to evaluate and, compare the accuracy of transabdominal ultrasonographic (US) and the progesterone (P4-RIA) and ovine pregnancy-associated glycoprotein (ovPAG-RIA) tests ... [more ▼]

The aim of the present study was to evaluate and, compare the accuracy of transabdominal ultrasonographic (US) and the progesterone (P4-RIA) and ovine pregnancy-associated glycoprotein (ovPAG-RIA) tests for the discrimination between single and multiple pregnancy in sheep. One hundred pregnant Awassi x Merino ewes were scanned by transabdominal ultrasonography (3.5 MHz linear-array transducer) at Days 43-56 and 81 of these ewes were scanned at Days 76-87 of gestation. The ewes were scanned in dorsal recumbency at the bare area of the inguinal regions (without pre-scanning shaving of the ventral abdominal wall). After each scan, blood samples were withdrawn from the jugular vein to estimate the levels of P4 and ovPAG by radioimmumoassay. At lambing, 61 ewes gave birth to single lambs and 39 ewes gave birth to multiples. The sensitivity of the transabdominal US, the P4-RIA and the ovPAG-RIA tests for determining ewes carrying multiples was 54, 64.1 and 64.1% at Days 43-56. At Days 76-87 of gestation these accuracies were 60.0, 66.7 and 76.6% for the US, P4-RIA and PAG-RIA tests, respectively. The specificity of the transabdominal US, the P4-RIA and the ovPAG-RIA tests for determining ewes carrying singles, was 78.6, 60.7 and 62.3% at Days 43-56 and 78.4, 64.7 and 70.6% at Days 76-87 of gestation, respectively. It is concluded that the accuracy of transabdominal ultrasonographic (without pre-scanning shaving of the ventral abdominal wall), the P4- and the ovPAG-RIA tests for determination of the fetal numbers in Awassi x Merino crossbred ewes is too low to be used in the field. (c) 2005 Elsevier Inc. All rights reserved. [less ▲]

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See detailEffect of number of lambs, their sex and birth weignt on ovine pregnancy associated glycoprotein (ovPAG) concentrations
Vandaele, L; Verberckmoes, S; De Cat, S et al

in Journal of Reproduction & Fertility. Abstract Series (2004), 16(2), 192193

Early pregnancy detection and prediction of the number of lambs would be profitable for sheep breeders, as this enables nourishment of pregnant ewes to their individual needs. Nonpregnant ewes can be ... [more ▼]

Early pregnancy detection and prediction of the number of lambs would be profitable for sheep breeders, as this enables nourishment of pregnant ewes to their individual needs. Nonpregnant ewes can be separated and sold before winter. Prediction of sex is interesting for the curiosity of impatient breeders. Early pregnancy detection (before 45 days after mating) by means of ovine pregnancy-associated glycoproteins (ovPAGs) has proved to be a more reliable test than the commonly used transrectal ultrasound. The concentration of ovPAG has been claimed to be related to the number of lambs, their sex and birth weight, but contradictory results were obtained in different small-scale studies. In this study the correlation between number of lambs, their sex and birth weight and the ovPAG concentration in the serum of the ewes was examined. In a field trial, 160 and 70 ewes of the Texel and Suffolk breed, respectively, housed on 6 different farms, were synchronized by means of intravaginal sponges impregnated with 40 mg cronolone (Chronogest®, Intervet, Boxmeer, The Netherlands). At the moment of synchronisation (T0) and at 25 (T25), 35 (T35) and 45 (T45) days after mating or artificial insemination, blood samples were taken by jugular vein puncture. A heterologous radioimmunoassay (RIA) was used to determine the ovPAG concentration. In the heterologous RIA boPAG molecules were used as tracer, and ovPAG molecules as standard, while rabbit antibodies against ovPAG were used as antiserum. At parturition, number, sex and birth weight of the lambs were registered and their effect on ovPAG concentrations was statistically evaluated. No significant difference in ovPAG concentration was found between ewes pregnant of a single male or female lamb (P = 0.29). ovPAG concentrations were affected by the total birth weight (P < 0.05). In ewes pregnant with multiples, the ovPAG concentrations were higher (P < 0.01) than in ewes pregnant with singles at T25, T35 and T45, respectively. Because ovPAG concentrations were affected by the farm, it was impossible to predict the number of lambs by the ovPAG level. In conclusion, ovPAG concentrations were not affected by the sex of the lamb. However, ovPAG concentrations were related to the total birth weight. Within the farm, increased ovPAG concentrations may indicate pregnancy of multiples. [less ▲]

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See detailOvine pregnancy-associated glycoprotein profiles in ewes pregnant with singletons or twins
Vandaele, L.; Verberckmoes, S.; Van Soom, A. et al

in Reproduction in Domestic Animals (2004), 39(4), 278

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See detailUse of heterologous and homologous radioimmunoassay (RIA) for ovine pregnancy-associated glycoprotein (ovPAG) determination to detect pregnancy in sheep
Vandaele, L.; Verberckmoes, S.; De Cat, S. et al

in Reproduction (Cambridge, England). Abstract Series (2004), 31

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See detailDiagnostic et suivi de gestation chez la chèvre et la brebis
Melo de Sousa, Noelita ULg; Gonzalez, F.; Karen, A. et al

Scientific conference (2004)

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See detailA new test for early pregnancy diagnosis in sheep: Determination of ovine pregnancy associated glycoprotein (ovPAG) concentration by means of a homologous radioimmunoassay
Verberckmoes, S.; Vandaele, Leen; De Cat, S. et al

in Vlaams Diergeneeskundig Tijdschrift (2004), 73(2, MAR-APR), 119-127

Early pregnancy diagnosis is a useful tool in the management of sheep breeding. In this study different methods for pregnancy diagnosis in sheep, including the assessment of ovine Pregnancy-Associated ... [more ▼]

Early pregnancy diagnosis is a useful tool in the management of sheep breeding. In this study different methods for pregnancy diagnosis in sheep, including the assessment of ovine Pregnancy-Associated Glycoproteins (ovPAGs), are briefly discussed. Subsequently, in a field trial the use of transrectal ultrasound is compared with the assessment of the concentration of ovPAGs for early pregnancy diagnosis. At the start of the breeding season in 2002, 192 Texel ewes at 4 different farms were synchronized and afterwards mated or artificially inseminated (AI). At the moment of synchronization (D-14) and at 25 (D25), 35 (D35) and 45 (1345) days after mating/AI, transrectal ultrasound was performed and blood was collected by jugular vein puncture. The ovPAG concentration in the plasma of the ewes was measured by means of a homologous radioimmunoassay (RIA). The specificity of transrectal ultrasound was 85%, and the sensitivity was 92% at D25, 94% at D35 and 95% at D45. The specificity of the homologous RIA was 100%, and the sensitivity was 99% at D25, and 100% at D35 and D45. Higher ovPAG concentrations were detected at D35 and D45 than at D25 (P<0.01). An interesting finding was that within the same breed (Texel), ovPAG concentrations were significantly affected by the farm (P<0.01). In conclusion, determination of ovPAG concentration by means of homologous RIA can be used for early pregnancy diagnosis in sheep and is more reliable than transrectal ultrasound at 25,35 or 45 days of gestation. [less ▲]

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See detailIsolation and characterization of eight pregnancy-associated glycoproteins present at high levels in the ovine placenta between day 60 and day 100 of gestation
El Amiri, B.; Remy, Benoit; Melo de Sousa, Noelita ULg et al

in Reproduction Nutrition Development (2004), 44(3, May-Jun), 169-181

Pregnancy-associated glycoproteins (PAG), structurally related to aspartic proteinases, are expressed in the outer epithelial cell layer (chorion/trophectoderm) of the ungulate placenta. The aim of the ... [more ▼]

Pregnancy-associated glycoproteins (PAG), structurally related to aspartic proteinases, are expressed in the outer epithelial cell layer (chorion/trophectoderm) of the ungulate placenta. The aim of the present study was to isolate as many PAG molecules as possible from placentae collected between day 60 and day 100 of gestation and to characterize their amino-terminal amino-acid sequences. Three heterologous radioimmunoassays were used to monitor PAG immunoreactivity throughout the isolation procedures. Sequential use of DEAE-cellulose, gel filtration, and CM ceramic chromatographies led to the isolation of several fractions rich in PAG immunoreactivity. The fractions with a large amount of proteins were also purified by chromatofocusing. The analysis of immunoreactive fractions by SDS-PAGE, Western blotting and two-dimensional electrophoresis followed by amino-terminal microsequencing on PVDF membranes allowed to identify eight different ovPAG with apparent molecular masses ranging from 55 to 66 kDa and isoelectric points from 4.0 to 6.8. The N-terminal sequences were determined and their comparison to those previously identified revealed that four of them are identical to those encoded by previously known cDNA, while the additional four sequences appear to be novel since they have not yet been described. [less ▲]

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See detailPregnancy diagnosis in sheep by means of ultrasound and ovine pregnancy-associated glycoprotein (ovPAGs)
Verberckmoes, S; Vandaele, L; De Cat, S et al

in Proceeding of pregnancy diagnosis in sheep by means of ultrasound and ovine pregnancy-associated glycoprotein (2003, November 17)

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See detailValidation of two homologous radioimmunoassays for measuring pregnancy-associated glycoprotein in ewes.
El Amiri, B.; Karen, A.; Sulon, J. et al

in Reproduction in Domestic Animals (2003), 38(4), 358

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See detailPregnancy-Associated Glycoprotein 55h [Fragment] from Ovis aries placenta - Access number P83500
El Amiri, B.; Remy, B.; Melo de Sousa, Noelita ULg et al

E-print/Working paper (2003)

N-terminal microsequence obtained after purification and characterization of placental proteins in ovine species. Proteins were submitted to SwissProt databank.

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See detailPregnancy-Associated Glycoprotein 59g [Fragment] from Ovis aries placenta - Access number P83499
El Amiri, B.; Remy, B.; Melo de Sousa, Noelita ULg et al

E-print/Working paper (2003)

N-terminal microsequence obtained after purification and characterization of placental proteins in ovine species. Proteins were submitted to SwissProt databank.

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See detailPregnancy-Associated Glycoprotein 60f [Fragment] from Ovis aries placenta - Access number P83498
El Amiri, B.; Remy, B.; Melo de Sousa, Noelita ULg et al

E-print/Working paper (2003)

N-terminal microsequence obtained after purification and characterization of placental proteins in ovine species. Proteins were submitted to SwissProt databank.

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See detailPregnancy-Associated Glycoprotein 66e [Fragment] from Ovis aries placenta - Access number P83497
El Amiri, B.; Remy, B.; Melo de Sousa, Noelita ULg et al

E-print/Working paper (2003)

N-terminal microsequence obtained after purification and characterization of placental proteins in ovine species. Proteins were submitted to SwissProt databank.

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See detailPregnancy-Associated Glycoprotein 66d [Fragment] from Ovis aries placenta - Access number P83496
El Amiri, B.; Remy, B.; Melo de Sousa, Noelita ULg et al

E-print/Working paper (2003)

N-terminal microsequence obtained after purification and characterization of placental proteins in ovine species. Proteins were submitted to SwissProt databank.

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See detailPregnancy-Associated Glycoprotein 58c [Fragment] from Ovis aries placenta - Access number - P83495
El Amiri, B.; Remy, B.; Melo de Sousa, Noelita ULg et al

E-print/Working paper (2003)

N-terminal microsequence obtained after purification and characterization of placental proteins in ovine species. Proteins were submitted to SwissProt databank.

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See detailPregnancy-Associated Glycoprotein 61b [Fragment] from Ovis aries placenta - Access number P83494
El Amiri, B.; Remy, B.; Melo de Sousa, Noelita ULg et al

E-print/Working paper (2003)

N-terminal microsequence obtained after purification and characterization of placental proteins in ovine species. Proteins were submitted to SwissProt databank.

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See detailPregnancy-Associated Glycoprotein 58a [Fragment] from Ovis aries placenta - Access number P83493
El Amiri, B.; Remy, B.; Melo de Sousa, Noelita ULg et al

E-print/Working paper (2003)

N-terminal microsequence obtained after purification and characterization of placental proteins in ovine species. Proteins were submitted to SwissProt databank.

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