References of "Beckers, Jean-François"
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See detailMicroscopic study of equine oocyte maturation within quaternary follicles
Ponthier, Jérôme ULg; Beckers, Jean-François ULg; Deleuze, Stefan ULg

in Comptes Rendus de l'Académie Bulgare des Sciences = Proceeding of the Bulgarian Academy of Sciences (2009), 62(4), 491-498

In various species a relationship between oocyte maturity and morphological characteristics of oocytes has been established. To our knowledge, little attention has been paid to the immature oocyte aspect ... [more ▼]

In various species a relationship between oocyte maturity and morphological characteristics of oocytes has been established. To our knowledge, little attention has been paid to the immature oocyte aspect under light microscopy in the equine. The aim of the study is to give a general description and analysis of the microscopic parameters of immature oocytes. Follicles from abattoir ovaries are punctured after measurement of their diameter and their cumulus-oocyte complexes are recovered. Different characters such as oocyte diameter, cumulus aspect, granulosity and polarity of ooplasm are observed under light microscopy. No correlation between the estral activity, follicle maturity, cumulus cells aspect, polarity and granulosity of ooplasm was observed. The thickness of zona pellucida differs between oocytes with polar or nonpolar ooplasm. No correlation was observed between the follicle and oocyte diameter and none of the other studied parameters showed an influence on the oocyte diameter. Results show that no character of the observed oocytes under light microscopy can be related to the follicular origin or to any other character. Further studies have to be done to compare these immature oocytes with mature ones and to find the ultrastructural origin of the characters observed under light microscopy. [less ▲]

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See detailPreliminary results obtained by RIA determination of the proteins associated to pregnancy (PAG) in goat and sheep.
Zamfirescu, S; Topoleanu, I; Beckers, Jean-François ULg

in Comptes Rendus de l'Académie Bulgare des Sciences = Proceeding of the Bulgarian Academy of Sciences (2009), 62(9), 1111-1118

In goat and sheep the glycoproteins associated to pregnancy (PAG) are not well studied. Their study in these species is very important in the evaluation of prediction of early pregnancy. Even though ... [more ▼]

In goat and sheep the glycoproteins associated to pregnancy (PAG) are not well studied. Their study in these species is very important in the evaluation of prediction of early pregnancy. Even though numerous research was done in order to investigate the physiological functions of placental proteins; the exact biofunction of the glycoproteins associated to pregnancy is still unknown. The objective of research was the study of dynamics of PAG in goats and ewes in the first stage of pregnancy (1–35 days after mating) and the determination of correlations with the reproductive status of females and to earlier stages of the pregnancy. The experiment was realized on 49 Saanen x Carpatina goats and 72 Merinos of Palas sheep from the biostation of the Research and Development Institute for Goat and Sheep, Palas Constanta. The females in normal reproduction season were monitored for the detection of estrus and mated naturally. Blood was collected by puncture of the jugular vein on days 0, 7, 14, 25 and 35 after mating (day 0). The serum was obtained after centrifuging at 1500 x g for 15 min and stored at −20 ◦C till RIA determination. RIA of the plasma with the purpose of detecting the concentration of proteins specific to pregnancy was realized in two experimental series in February and December 2008, at the Laboratory for Reproduction Physiology, Faculty of Veterinary Medicine, Liege, Belgium. RIA dosing was realized after application of the method with preincubation of the serums to test with specific serum (Atg◦) and then with the marked antigen (Atg∗), considering the high sensitivity of this method to detect the smallest values of PAG from day 0 to day 35 after mating. The diagnosis of the pregnancy state was based on the principle of PAG antibodies binding to the specific antigen, establishing through RIA the quantity of free antigen. Nonpregnancy involves the attachment of the antigen marked by non-specific antibodies. The preliminary results demonstrated that the sheep PAG had values ranging between 4.197–15.985 ng/ml and 0.01–3.39 ng/ml in nonpregnant ewes. In pregnant goats PAG concentrations ranged between 16.75±3.44 − 27.17±2.95 ng/ml, while in nonpregnant goats, PAG values were 1.38±0.35 − 2.03±0.51 6 ng/ml. The purpose of the experiments was to find one accurate method for early pregnancy diagnosis in goat and sheep. The conclusion was that ovine pregnancy can be reliably diagnosed on day 25 after AI and goat pregnancy on day 30, by using a heterologous radioimmunoassay of PAG. [less ▲]

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See detailPurification de protéines associées à la gestation (PAG) chez le porc
Dethier, M.; Melo de Sousa, Noelita ULg; Balci, S. et al

Poster (2009)

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See detailPregnancy-Associated Glycoprotein H-63 kDa [Fragment] from Bubalus bubalis placenta - Access number P86379
Barbato, O.; Melo de Sousa, Noelita ULg; Barile, V. L. et al

E-print/Working paper (2009)

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

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See detailPregnancy-Associated Glycoprotein G-76 kDa [Fragment] from Bubalus bubalis placenta - Access number P86378
Barbato, O.; Melo de Sousa, Noelita ULg; Barile, V. L. et al

E-print/Working paper (2009)

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

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See detailPregnancy-Associated Glycoprotein F-58 kDa [Fragment] from Bubalus bubalis placenta - Access number P86377
Barbato, O.; Melo de Sousa, Noelita ULg; Barile, V. L. et al

E-print/Working paper (2009)

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

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See detailPregnancy-Associated Glycoprotein E-65 kDa [Fragment] from Bubalus bubalis placenta - Access number P86376
Barbato, O.; Melo de Sousa, Noelita ULg; Barile, V. L. et al

E-print/Working paper (2009)

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

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See detailEmbryo transfer as a tool for experimental reproduction of ovine herds.
Rizzo, H.; François, D.; Fassier, T. et al

in Ciência Animal Brasileira (2009), Suppl 1

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See detailValidation of a new pregnancy-associated glycoprotein radioimmunoassay method for the detection of early pregnancy in ewes.
Barbato, Olimpia; Melo de Sousa, Noelita ULg; Debenedetti, A. et al

in Theriogenology (2009), 72

The aim of the current study was to describe the use of a pool of different antisera raised against pregnancy-associated glycoproteins (PAGs; purified from both ovine and caprine placentas) for early ... [more ▼]

The aim of the current study was to describe the use of a pool of different antisera raised against pregnancy-associated glycoproteins (PAGs; purified from both ovine and caprine placentas) for early pregnancy diagnosis in ovine species. Sixty-three pluriparous Sarda ewes (Ovis aries) were synchronized. Blood samples were withdrawn on Days 18, 24, 26, 28, 30, and 50 after mating. These samples were assayed for progesterone (radioimmunoassay [RIA] including an extraction step) and for pregnancy-associated glycoproteins (RIA-706 and RIA-srPool). Progesterone concentrations were under 1.0ng/mL in all nonpregnant Sarda ewes. In pregnant ewes, mean progesterone concentrations ranged from 2.4ng/mL (Day 24, single pregnancies) to 4.4ng/mL (Day 28, multiple pregnancies). During all periods of examination, PAGs remained lower than 0.8ng/mL in nonpregnant ewes. On Day 18 of pregnancy, PAG concentrations could be detected in 26 of 43 (60.5%) and in 41 of 43 (95.3%) pregnant ewes using the RIA-706 and RIA-srPool methods, respectively. From Day 24 to Day 50, using both RIA methods, PAGs could be detected in all pregnant ewes. On Day 24, the best threshold for pregnancy diagnosis was obtained by use of RIA-srPool, maximal concentration in nonpregnant ewes being 0.3ng/mL and minimal concentration in pregnant ewes being 4.8ng/mL. In general, progesterone and PAG concentrations were higher in multiple pregnancies than in single pregnancies. However, because of large individual variations, single pregnancies could not be differentiated from multiple pregnancies [less ▲]

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See detailFactors Affecting Plasma Pregnancy-associated Glycoprotein 1 Concentrations Throughout Gestation in High-producing Dairy Cows.
Serrano, B.; Lopez-Gatius, F.; Santolaria, P. et al

in Reproduction in Domestic Animals (2009), 44(4), 600-605

This study was designed to establish the factors, if any, which could affect plasma pregnancy-associated glycoprotein-1 (PAG-1) expression in a study population of 87 pregnant, high-producing dairy cows ... [more ▼]

This study was designed to establish the factors, if any, which could affect plasma pregnancy-associated glycoprotein-1 (PAG-1) expression in a study population of 87 pregnant, high-producing dairy cows. The factors examined were: semen providing breed (Holstein-Friesian vs Limousin), outcome of gestation (male vs female newborn, and singleton vs twin pregnancies), lactation number, milk production at pregnancy diagnosis, plasma progesterone concentration, season of gestation (warm period, March-November vs cool period, December-February), and day of gestation (40, 90, 120, 150, 180 and 210). Pregnancy was diagnosed by transrectal ultrasound on day 40 post-insemination and by palpation per rectum on days 90, 120, 150, 180 and 210. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The relative contributions of the different factors on PAG-1 concentrations were evaluated by GLM repeated measures analysis of variance. No significant effects of the herd, foetal sex, milk production, lactation number and plasma progesterone concentrations were observed. In contrast, twin pregnancy, the use of Limousin semen and conception during the cool period were correlated with significantly increased plasma PAG-1 concentrations throughout gestation. Our data indicate that both cow well-being during early placental development, determined in our conditions by reduced heat stress when conception occurred in the cool season, and crossbreed pregnancies lead to improved PAG-1 production throughout the gestation period. [less ▲]

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See detailEffects of intraovarian application of insulin-like growth factor-1 (IGF-1) on the superovulatory response of diary cattle.
Velazquez, M. A.; Hadeler, K. G.; Beckers, Jean-François ULg et al

in Reproduction in Domestic Animals (2009), 44(S1), 38

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See detailMonitoring certain endocrine parameters for predicting stillbirth in dairy cows
Szenci, Otto; Bajcsy, A Cs; Brydl, E. et al

in Proceedings: XVII International congress of mediterranean federation of health and production of ruminants (2009)

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See detailDosage des pepsinogènes A et C dans le sang pour diagnostiquer les verminoses gastro-intestinales chez le bovin
Beckers, Jean-François ULg; Melo de Sousa, Noelita ULg; Dufrasne, Michel et al

in Nouvelles du Printemps (Les) (2009), (2e trimestre), 32-33

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See detailFactors affecting plasma prolactin concentrations throughout gestation in high producing dairy cows.
Garcia-Ispierto, I.; Lopez-Gatius, F.; Almeria, S. et al

in Domestic Animal Endocrinology (2009), 36(2), 57-66

The aim of the present study was to investigate possible relationships between plasma concentrations of prolactin and the following factors throughout gestation in lactating dairy cows: photoperiod ... [more ▼]

The aim of the present study was to investigate possible relationships between plasma concentrations of prolactin and the following factors throughout gestation in lactating dairy cows: photoperiod, season, milk production, Neospora caninum-seropositivity, twin pregnancy, and plasma concentrations of pregnancy associated glycoproteins-1 (PAG-1), progesterone and cortisol. Pregnancy was diagnosed by trans-rectal ultrasonography on Day 40 post-insemination and by palpation per rectum on Days 90, 120, 150, 180 and 210 or until abortion in aborting cows. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The study population was comprised of 73 non-aborting (54 Neospora-seropositive cows) and 20 aborting cows (all Neospora-seropositive) cows. In non-aborting cows, GLM repeated measures of analysis of variance revealed that lactation number and days in milk had no effect on plasma prolactin concentrations throughout gestation, whereas high plasma prolactin concentrations were significantly associated with high plasma levels of cortisol and PAG-1, with Neospora-seropositivity, positive photoperiod (increasing day length), twin pregnancy, and with low plasma progesterone concentrations. An interaction among plasma prolactin, plasma cortisol and milk production was observed in that plasma prolactin concentrations differed significantly throughout gestation and were highest in high-producing cows with high cortisol levels. In Neospora-seropositive non-aborting versus aborting cows, mean prolactin concentrations failed to differ on Days 40, 90, 120, 150 and 180 of pregnancy, whereas prolactin values were significantly lower (P=0.03) in aborting animals on Day 210 of pregnancy. Our results indicate that a positive photoperiod and Neospora-infection lead to increased plasma prolactin concentrations throughout gestation. Reduced prolactin concentrations detected in Neospora-seropositive aborting cows compared to non-aborting animals suggests a protective effect of prolactin in N. caninum infection. [less ▲]

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See detailPregnancy patterns during the early fetal period in high producing dairy cows treated with GnRH or progesterone.
Bech-Sabat, G.; Lopez-Gatius, F.; Garcia-Ispierto, I. et al

in Theriogenology (2009), 71

In order to explore pregnancy patterns in high producing dairy cows treated with GnRH or progesterone at pregnancy diagnosis (Days 28-34), two consecutive experiments were designed. In Experiment 1, cows ... [more ▼]

In order to explore pregnancy patterns in high producing dairy cows treated with GnRH or progesterone at pregnancy diagnosis (Days 28-34), two consecutive experiments were designed. In Experiment 1, cows bearing a single embryo were randomly assigned to a PRID (n=40; cows fitted with a progesterone releasing intra-vaginal device for 28 days), GnRH (n=40; cows receiving GnRH) or Control (n=26; untreated cows) group. PRID treatment led to a rise in plasma progesterone concentrations in the 7 days following the onset of treatment compared to the other two groups. In Experiment 2, in which we also examined twin pregnancies, animals were randomly assigned to PRID (n=312) or GnRH (n=294) treatment groups. Treatments were the same as described for Experiment 1. Logistic regression procedures revealed that in cows with a single corpus luteum, the probability of pregnancy loss between the first (Days 28-34) and second (Days 65-62) pregnancy diagnosis decreased by a factor of 0.51 in the PRID group compared to the GnRH group. However, in cows with two or more corpora lutea, PRID treatment increased the likelihood of pregnancy loss by a factor of three, compared to GnRH treatment. In cows carrying twins, the conceptus reduction rate was higher (P=0.02) for the GnRH (36%) than for the PRID (16.4%) group. Formation of a new corpus luteum was recorded in 17.7% of cows in the GnRH group. Our results indicate that compared to GnRH treatment, progesterone treatment given at pregnancy diagnosis in high producing dairy cows, reduced by a factor of 0.51 and increased by a factor of 3 the probability of pregnancy loss in cows with a single or with two or more corpora lutea, respectively, and reduced the conceptus reduction rate in cows carrying twins. The practical implications of our findings are that in herds with a high incidence of early fetal loss of a non-infectious nature, treatment at the time of pregnancy diagnosis with PRID in cows with one corpus luteum and with GnRH in cows with two or more corpora lutea should offer considerable benefits. [less ▲]

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See detailFirst birth of an animal from an extinct subspecies (Capra pyrenaica pyrenaica) by cloning
Folch, J.; Cocero, M. J.; Chesne, P. et al

in Theriogenology (2009), 71

Two experiments have been performed to clone the bucardo, an extinct wild goat. The karyoplasts were thawed fibroblasts derived from skin biopsies, obtained and cryopreserved in 1999 from the last living ... [more ▼]

Two experiments have been performed to clone the bucardo, an extinct wild goat. The karyoplasts were thawed fibroblasts derived from skin biopsies, obtained and cryopreserved in 1999 from the last living specimen, a female, which died in 2000. Cytoplasts were mature oocytes collected from the oviducts of superovulated domestic goats. Oocytes were enucleated and coupled to bucardo's fibroblasts by electrofusion. Reconstructed embryos were cultured for 36h or 7d and transferred to either Spanish ibex or hybrid (Spanish ibex malex domestic goat) synchronized recipients. Embryos were placed, according to their developmental stage, into the oviduct or into the uterine horn ipsilateral to an ovulated ovary. Pregnancy was monitored through their plasmatic PAG levels. In Experiment 1, 285 embryos were reconstructed and 30 of them were transferred at the 3- to 6-cells stage to 5 recipients. The remaining embryos were further cultured to day 7, and 24 of them transferred at compact morula/blastocyst stage to 8 recipients. In Experiment 2, 154 reconstructed embryos were transferred to 44 recipients at the 3- to 6-cells stage. Pregnancies were attained in 0/8 and 7/49 of the uterine and oviduct-transferred recipients, respectively. One recipient maintained pregnancy to term, displaying very high PAG levels. One morphologically normal bucardo female was obtained by caesarean section. The newborn died some minutes after birth due to physical defects in lungs. Nuclear DNA confirmed that the clone was genetically identical to the bucardo's donor cells. To our knowledge, this is the first animal born from an extinct subspecies. [less ▲]

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See detailGamma interferon production correlates negatively with plasma levels of pregnancy-associated glycoprotein-1 (PAG-1) during gestation in dairy cows naturally infected with Neospora caninum
Lopez-Gatius, F.; Almeria, S.; Yániz, J. L. et al

in O’Leary, M.; Arnett, J. (Eds.) Pregnancy Protein Research (2009)

Gamma interferon (IFN-γ) production has been ascribed a role in protecting cows infected with Neospora caninum against abortion. The present study analyzes the interaction between IFN-γ production and ... [more ▼]

Gamma interferon (IFN-γ) production has been ascribed a role in protecting cows infected with Neospora caninum against abortion. The present study analyzes the interaction between IFN-γ production and levels of plasma pregnancy-associated glycoprotein-1 (PAG-1), as a marker of placental/fetal well-being, throughout gestation in naturally Neospora-infected dairy cows. Data were obtained from 88 pregnant cows from two herds: 62 seropositive and 26 seronegative for the parasite. Blood sample collection was performed on days 40, 90, 120, 150, 180 and 210 of gestation. Plasma was tested for antibodies against N. caninum, PAG-1 and IFN-γ. Twenty five (28.4%) pregnancies were recorded after AI using Holstein-Friesian semen (19 in seronegative and 6 in seropositive animals), and 63 (71.6%) after AI using Limousin semen (7 in seronegative and 56 in seropositive animals). Gamma interferon was detected in the plasma of 14 (22.6%) of the 62 Neospora-seropositive cows and could not be detected in any of the 26 seronegative animals. All 14 cows producing IFN-γ became pregnant by using Limousin semen. Our GLM repeated measures showed no effect of herd, lactation number, milk production at the time of pregnancy diagnosis and Neospora-seropositivity on plasma PAG-1 concentrations. Significant positive effects of both the day of gestation (P<0.0001) and interaction between day of gestation and breed of sire (P = 0.001) on PAG-1 values were registered. Cows carrying twins had higher (P = 0.002) PAG-1 concentrations throughout gestation than cows carrying singletons. Interactions between breed of sire and Neospora-seropositivity (P<0.0001), and between IFN-γ production and Neospora-seropositivity (P = 0.04) were also detected. Thus, Neospora-seronegative cows inseminated with Limousin and Neospora-seropositive cows with no IFN-γ production, exhibited higher PAG-1 concentrations throughout gestation than seropositive cows inseminated with Limousin semen and producing IFN-γ, respectively. Our data indicate that production of IFN-γ correlates negatively and, the production of antibodies against N. caninum is uncorrelated with plasma PAG-1 concentrations during gestation in Neospora-infected dairy cows. Our results also suggest that augmented Th1 cell-mediated immunity is related to a lower risk of abortion and therefore higher resistance to the parasite in cows inseminated with Limousin versus Holstein-Friesian semen. [less ▲]

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See detailPregnancy-Associated Glycoprotein D-76 kDa [Fragment] from Bubalus bubalis placenta - Access number P86375
Barbato, O.; Melo de Sousa, Noelita ULg; Barile, V. L. et al

E-print/Working paper (2009)

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

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See detailPregnancy-Associated Glycoprotein C-61 kDa [Fragment] from Bubalus bubalis placenta - Access number P86374
Barbato, O.; Melo de Sousa, Noelita ULg; Barile, V. L. et al

E-print/Working paper (2009)

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

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See detailPregnancy-Associated Glycoprotein B-73 kDa [Fragment] from Bubalus bubalis placenta - Access number P86373
Barbato, O.; Melo de Sousa, Noelita ULg; Barile, V. L. et al

E-print/Working paper (2009)

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

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