References of "Beckers, Jean-François"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailNeospora caninum and coxiella burnetii seropositivity are related to endocrine pattern changes during gestation in lactating dairy cows.
Garcia-Ispierto, I.; Nogareda, C.; Yaniz, J. L. et al

in Theriogenology (2010), 74(2), 212-230

Q fever is a zoonotic infection caused by Coxiella burnetii that is endemic worldwide. Domestic ruminants are a source of infection for humans. Given the suggestion that the bacterium recrudesces during ... [more ▼]

Q fever is a zoonotic infection caused by Coxiella burnetii that is endemic worldwide. Domestic ruminants are a source of infection for humans. Given the suggestion that the bacterium recrudesces during pregnancy in cattle, this study was designed to determine whether C. burnetii infection affects hormonal patterns, such as progesterone, cortisol, pregnancy associated glycoproteins (PAG), and prolactin during gestation in lactating cows. Possible interactions with Neospora caninum were also explored. The study was performed on 58 gestating non-aborting cows. Blood samples for hormone determinations were collected on Days 40, 90, 120, 150, 180, and 210 of gestation. For antibody determinations, blood was collected at day 40 postinsemination and postpartum. By GLM repeated measures analysis of variance, we established the effects of production and reproductive variables as well as Coxiella and Neospora seropositivity related to changes on cortisol, PAG, progesterone, and prolactin levels. Coxiella antibody levels were significantly related to cortisol, PAG, and plasma progesterone concentrations, whereas Neospora seropositivity was linked to plasma progesterone concentrations. The interaction between Coxiella and Neospora seropositivity was correlated with cortisol and plasma progesterone levels, whereas the interaction seropositivity against C. burnetii-plasma cortisol concentration was related to plasma PAG levels. Finally, an effect of lactation number only was observed on plasma prolactin. Our findings suggest that both the N. caninum and C. burnetii infection or the presence of both modify endocrine patterns throughout gestation. Cows seropositive to both, Neospora and Coxiella, showed higher plasma progesterone levels than the remaining animals examined. Seropositivity to C. burnetii was associated with placental damage and diminishing PAG levels throughout the second half of gestation, along with increased plasma cortisol levels on Day 180 of gestation. [less ▲]

Detailed reference viewed: 47 (8 ULg)
Full Text
Peer Reviewed
See detailPregnancy-associated Glycoprotein Profile during the First Trimester of Pregnancy in Egyptian Buffalo Cows.
El-Battawy, K. A.; Melo de Sousa, Noelita ULg; Szenci, Otto et al

in Reproduction in Domestic Animals (2009), 44(2), 161166

Pregnancy-associated glycoprotein (PAG) concentrations were measured in buffalo cows starting from day 28 after breeding. Oestrus was synchronized in 10 buffaloes using two injections of 25 mg ... [more ▼]

Pregnancy-associated glycoprotein (PAG) concentrations were measured in buffalo cows starting from day 28 after breeding. Oestrus was synchronized in 10 buffaloes using two injections of 25 mg prostraglandin (PG)F(2alpha) (Lutalyse((R))) at a 11-day interval. Blood sampling was conducted nearly twice weekly. Results indicated that plasma PAG concentrations in non-pregnant buffaloes were low (<0.20 ng/ml) during the whole experimental period (day 28 to 103), while in pregnant animals plasma PAG levels increased from day 28 (4.48 +/- 0.92 ng/ml) until day 41 (27.27 +/- 6.74 ng/ml), remaining high (20.71 +/- 9.20 ng/ml) until day 103. Progesterone levels were significantly (p < 0.0001) higher in pregnant (3.51-4.80 ng/ml) than in non-pregnant buffaloes (0.28-1.52 ng/ml). A significant difference (p < 0.0001) in plasma PAG concentrations between pregnant and non-pregnant animals starting at day 28 after breeding suggests that PAG-radioimmunoassay could be suitable for pregnancy diagnosis in buffaloes during this period. In conclusion, PAG test offers the advantages that it requires a single plasma sample for early pregnancy diagnosis as well as the accuracy of the test for the detection of pregnancy as early as day 28. [less ▲]

Detailed reference viewed: 61 (7 ULg)
Peer Reviewed
See detailMicroscopic study of equine oocyte maturation within quaternary follicles.
Ponthier, Jérôme ULg; Beckers, Jean-François ULg; Deleuze, Stefan ULg

Conference (2009, February 19)

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

In various species a relationship between oocyte maturity and morphological characteristics of oocytes has been established. To our knowledge, immature oocyte aspect under light microscopy has been paid little attention in the equine. The aim of the study is to give a general description and analyse 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 estral activity, follicle maturity, cumulus cells aspect, polarity and granulosity of ooplasm was observed. Thickness of zona pellucida differs between oocytes with polar or non polar ooplasm. No correlation was observed between follicle diameter and oocyte diameter and none of the other studied parameters showed an influence on oocyte diameter. Results show that no character of oocytes observed under light microscopy can be related to follicular origin or to any other character. Further studies have to be done to compare these immature oocytes with mature oocytes and to find the ultra-structural origin of characters observed under light microscopy. [less ▲]

Detailed reference viewed: 96 (34 ULg)
Full Text
See detailTransferêcia de embrioes como ferramenta para formaçao de rebanho experimental ovino
Rizzo, Huber; François, Dominique; Fassier, T et al

in Ciência Animal Brasileira (2009), Suppl 1

Detailed reference viewed: 7 (0 ULg)
Full Text
Peer Reviewed
See detailDetection of placental lactogens in Swamp buffalo by radioimmunoassay technique.
Hanh, N. V.; Huu, Q. X.; Uoc, N. T. et al

in Reproduction, Fertility and Development (2009), 21(1), 152-153

Detailed reference viewed: 6 (3 ULg)
Full Text
Peer Reviewed
See detailDetection of placental lactogens in swamp buffalo by radioimmunoassay technique
Hanh, N. V.; Huu, Q. X.; Uoc, N. T. et al

in Reproduction, Fertility and Development (2009), 21(1), 152-153

Ruminant placental lactogens (PL) are members of the growth factor/prolactin (GH/PRL) family. They are synthesized by trophectodermal binucleate cells. There is evidence to suggest that PL is involved in ... [more ▼]

Ruminant placental lactogens (PL) are members of the growth factor/prolactin (GH/PRL) family. They are synthesized by trophectodermal binucleate cells. There is evidence to suggest that PL is involved in control of fetal growth, through actions in both the maternal and fetal compartments, as well as in influencing mammary growth during pregnancy (Byatt JC et al. 1992 J. Anim. Sci. 70, 2911–2923). The structure and biology of PL have been studied in the cow, sheep, goat, human, and mice. The maternal concentration of PL is 100- to 1 000-fold greater in pregnant sheep and goats than in cows but no information exists about PL concentration in buffalo. The aim of the present study was to evaluate the ability to detect PL in buffalo fluids by using bovine PL antibody. Samples were collected in the slaughterhouse immediately after animal slaughter. The fetuses were measured after heart blood collection. A bPL RIA system was used to determine the bPL concentrations in the buffalo samples (Alvarez-Oxiley AV et al. 2007 Reprod. Fertil. Dev. 19, 877–885). The rbPL molecules were radio-iodinated with [125]I-Na by using the lactoperoxidase method (Thorell JI and Johansson BG 1971 Biochim. Biophys. Acta 251, 363–369). Concentrations of buffalo PL are presented in Table 1. In this RIA system, the minimum detected value was 0.068 ng mL–1, and the binding competition curves of bovine PL standard and buffalo fluids dilution using bovine PL antibody were paralleled in all kinds of samples. The lowest concentration was detected in allantoid fluid and the greatest concentration in fetal plasma (P < 0.05). Study of the biology of PL in buffalo has proved difficult because the concentration of PL in all buffalo fluids is very low. Furthermore, the research concerning buffalo PL function required in vivo experiments. Existing data suggest that at least the concentration of buffalo PL is different from cattle and other smaller domestic ruminants. In conclusion, our results provide preliminary information about concentrations of PL in buffalo fluids. [less ▲]

Detailed reference viewed: 17 (2 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 62 (7 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 24 (2 ULg)
Full Text
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)

Detailed reference viewed: 19 (2 ULg)
Full Text
Peer Reviewed
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.

Detailed reference viewed: 13 (0 ULg)
Full Text
Peer Reviewed
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.

Detailed reference viewed: 10 (0 ULg)
Full Text
Peer Reviewed
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.

Detailed reference viewed: 9 (0 ULg)
Full Text
Peer Reviewed
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.

Detailed reference viewed: 10 (0 ULg)
Full Text
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

Detailed reference viewed: 11 (3 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 55 (8 ULg)
Full Text
Peer Reviewed
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 ▲]

Detailed reference viewed: 51 (7 ULg)
Full Text
Peer Reviewed
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

Detailed reference viewed: 21 (2 ULg)
Full Text
Peer Reviewed
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)

Detailed reference viewed: 56 (11 ULg)
Full Text
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

Detailed reference viewed: 104 (16 ULg)