Jean-François Beckers

Comparison of accuracy of ultrasonography, progesterone and pregnancy-associated 4 glycoprotein tests for pregnancy diagnosis in semi-domesticated reindeer (2009)

Savela, Hannele, Vahtiala, S, Lindeberg, H, Dahl, E, Ropstad, E, Beckers, Jean-François, ...

The aim of the study was to compare transrectal ultrasound with progesterone (P4) and pregnancy-associated glycoproteins (PAG) as pregnancy detection methods for semi-domesticated reindeer in field...

Pregnancy-Associated Glycoprotein and Progesterone Concentrations during Pregnancy Failure in Bedouin Goat from the Southwest of Algeria. (2009)

Charallah, Salima, Amirat, Z, Sulon, Joseph, Khammar, F, Beckers, Jean-François

Contents Thirteen female Bedouin goats living in arid land of Algeria Sahara desert were used in this study. These goats were pregnant but they sustained an abortion because of unidentified causes....

Validation of a new pregnancy-associated glycoprotein radioimmunoassay method for the detection of early pregnancy in ewes. (2009)

Barbato, Olimpia, Melo De Sousa, Noelita, Debenedetti, A, Canali, C, Todini, L, Beckers, Jean-François

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-associated Glycoprotein Profile during the First Trimester of Pregnancy in Egyptian Buffalo Cows. (2009)

El-Battawy, KA, Melo De Sousa, Noelita, Szenci, Otto, Beckers, Jean-François

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...

Factors affecting plasma prolactin concentrations throughout gestation in high producing dairy cows. (2009)

Garcia-Ispierto, I, Lopez-Gatius, F, Almeria, S, Yaniz, J, Santolaria, P, Serrano, B, ...

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,...

First birth of an animal from an extinct subspecies (Capra pyrenaica pyrenaica) by cloning (2009)

Folch, J, Cocero, MJ, Chesne, P, Alabart, JL, Dominguez, V, Cognie, Y, ...

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...

Pregnancy patterns during the early fetal period in high producing dairy cows treated with GnRH or progesterone. (2009)

Bech-Sabat, G, Lopez-Gatius, F, Garcia-Ispierto, I, Santolaria, JP, Serrano, B, Nogareda, C, ...

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,...

Serum Profiles of Pregnancy-Associated Glycoprotein, Oestrone Sulphate and Progesterone During Gestation and Some Factors Influencing the Profiles in Ethiopian Borana and Crossbred Cattle. (2009)

Lobago, F, Bekana, M, Gustafsson, H, Beckers, Jean-François, Yohannes, G, Aster, Y, ...

Contents This study presents serum concentrations of pregnancy-associated glycoprotein (PAG), oestrone sulphate (E1-S) and progesterone (P4), and the effects of some dam and foetus-related factors on...

Factors Affecting Plasma Pregnancy-associated Glycoprotein 1 Concentrations Throughout Gestation in High-producing Dairy Cows. (2009)

Serrano, B, Lopez-Gatius, F, Santolaria, P, Almeria, S, Garcia-Ispierto, I, Bech-Sabat, G, ...

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...

Anomalous Pregnancies during Late Embryonic/Early Foetal Period in High Producing Dairy Cows. (2009)

Serrano, B, Lopez-Gatius, F, Hunter, R, Santolaria, P, Garcia-Ispierto, I, Bech-Sabat, G, ...

This study analyses anomalous cases of gestation ending in pregnancy loss during the early foetal period and their effect on progesterone and plasma pregnancy-associated glycoprotein-1 (PAG-1)...

Microscopic study of equine oocyte maturation within quaternary follicles (2009)

Ponthier, Jérôme, Beckers, Jean-François, Deleuze, Stefan

In various species a relationship between oocyte maturity and morpho- logical characteristics of oocytes has been established. To our knowledge, little attention has been paid to the immature oocyte...

Monitoring certain endocrine parameters for predicting stillbirth in dairy cows (2009)

Szenci, Otto, Bajcsy, A Cs, Brydl, E, Madl, I, Tibold, J, Melo De Sousa, Noelita, ...

XVII International Congress of Mediterranean Federation of Health and Production of Ruminants

Determination of sex and scrapie resistance genotype in preimplantation ovine embryos. (2009)

Guignot, Florence, Baril, Gerard, Dupont, Francis, Cognié, Yves, Folch, Jose, Alabart, Jose Luis, ...

The aim of this study was to test the accuracy of genotype diagnosis after pre-amplification of DNA extracted from biopsies obtained by microblade cutting of ovine embryos and to evaluate the...

Anti-mullerian hormone is an endocrine marker of ovarian gonadotropin-responsive follicles and can help to predict superovulatory responses in the cow. (2009)

Rico, Charlene, Fabre, Stephane, Medigue, Claire, Di Clemente, Nathalie, Clement, Frederique, Bontoux, Martine, ...

The major limitation to the development of embryo production in cattle is the strong between-animal variability in ovulatory response to FSH-induced superovulation, mainly due to differences in...

Isolation of pregnancy-associated glycoproteins of the American bison (Bison bison) at first half of pregnancy (2008)

Kiewisz, J, Melo De Sousa, Noelita, Beckers, Jean-François, Vervaecke, H, Panasiewicz, G, Szafranska, B

This paper describes the successful purification and characterisation of pregnancy-associated glycoproteins (PAG) extracted from placenta (3-4 months) of American bisons (Amb). Chorionic AmbPAG...

Les glycoproteines placentaires chez les mammiferes (2008)

Clerget, E, Melo De Sousa, Noelita, Bella, Amina, Maghuin-Rogister, Guy, Beckers, Jean-François

Placental tissue exhibits a typical glycosylation pattern, which differs from that observed in the pituitary gland. Depending to the species and pregnancy period, the placenta synthesizes diverse...

Meiotic segregation analysis in cows carrying the t(1;29) Robertsonian translocation. (2008)

Bonnet-Garnier, A, Lacaze, S, Beckers, Jean-François, Berland, HM, Pinton, A, Yerle, M, ...

Heterozygous carriers of Robertsonian translocations generally have a normal phenotype but present reproductive failure. In cattle, the t(1;29) Robertsonian translocation is very common and carriers...

Anomalous Pregnancies during Late Embryonic/Early Foetal Period in High Producing Dairy Cows. (2008)

Serrano, B, Lopez-Gatius, F, Hunter, R, Santolaria, P, Garcia-Ispierto, I, Bech-Sabat, G, ...

This study analyses anomalous cases of gestation ending in pregnancy loss during the early foetal period and their effect on progesterone and plasma pregnancy-associated glycoprotein-1 (PAG-1)...

Identification of multiple pregnancy-associated glycoproteins (PAGs) purified from the European bison (Eb; Bison bonasus L.) placentas. (2008)

Kiewisz, J, Melo De Sousa, Noelita, Beckers, Jean-François, Panasiewicz, G, Gizejewski, Z, Szafranska, B

This paper describes the first identified chorionic PAGs in the European bison (Eb), named EbPAGs, predominantly expressed during early and mid-pregnancy (45-120 day post-coitum; dpc). Many EbPAGs...

Pregnancy-associated glycoprotein secretion in North Moroccan goats (2008)

Chentouf, M, El Amiri, B, Sulon, Joseph, Beckers, Jean-François, Kirschvink, N, Boulanouar, B, ...

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)....

Pregnancy incidence in Norwegian red cows using nonreturn to estrus, rectal palpation, pregnancy-associated glycoproteins, and progesterone. (2008)

Garmo, R T, Refsdal, A O, Karlberg, K, Ropstad, E, Waldmann, A, Beckers, Jean-François, ...

The objectives of the study were to estimate pregnancy incidence and calving rate after first artificial insemination (AI) in Norwegian Red cows undergoing spontaneous estrus, to assess the...

Isolation of new pregnancy-associated glycoproteins from water buffalo (Bubalus bubalis) placenta by Vicia villosa affinity chromatography. (2008)

Barbato, O, Melo De Sousa, Noelita, Klisch, K, Clerget, E, Debenedetti, A, Barile, V L, ...

The present study describes the isolation and characterization of new pregnancy-associated glycoprotein molecules (PAG) from midpregnancy and late-pregnancy placentas in the water buffalo (Bubalus...

Factors affecting plasma progesterone in the early fetal period in high producing dairy cows. (2008)

Bech-Sabat, G, Lopez-Gatius, F, Yaniz, J L, Garcia-Ispierto, I, Santolaria, P, Serrano, B, ...

The aim of the present study was to determine whether certain animal- or management related factors could affect plasma progesterone concentrations on Day 42 of gestation in high producing dairy...

Correlation of five radioimmunoassay systems for measurement of bovine plasma pregnancy-associated glycoprotein concentrations at early pregnancy period. (2008)

Ayad, A, Sousa, NM, Sulon, Joseph, Hornick, Jean-Luc, Iguer-Ouada, M, Beckers, Jean-François

The measurement of serum or plasma PAG concentrations is currently used as a specific method for pregnancy diagnosis in cattle. In this study, the correlation between five radioimmunoassay systems...

Identification of multiple pregnancy-associated glycoproteins (PAGs) purified from the European bison (Eb; Bison bonasus L.) placentas. (2008)

Kiewisz, J, Melo De Sousa, Noelita, Beckers, Jean-François, Panasiewicz, G, Gizejewski, Z, Szafranska, B

This paper describes the first identified chorionic PAGs in the European bison (Eb), named EbPAGs, predominantly expressed during early and mid-pregnancy (45-120 day post-coitum; dpc). Many EbPAGs...

Thyrotropin in newborn calves as a tool for diagnosing hypothyroidism (2007)

Guyot, Hugues, Lebreton, P, Sulon, Joseph, Beckers, Jean-François, Rollin, Frédéric

The hypothalamic-pituitary-thyroid axis is of particular importance for the adaptation of mammals to their environment. Hypothyroidism is the most common type of thyroid disorders in cattle....

Accuracy of ultrasonography and pregnancy-associated glycoprotein test for pregnancy diagnosis in buffaloes (2007)

Karen, A, Darwish, S, Ramoun, A, Tawfeek, K, Van Hanh, N, Melo De Sousa, Noelita, ...

The aims of the present study were to evaluate and compare the accuracy of transrectal ultrasonography and pregnancy-associated glycoprotein radioimmunoassay (PAG-RIA) test for diagnosis of pregnancy...

Development and validation of a radioimmunoassay for thyrotropin in cattle (2007)

Guyot, Hugues, Sulon, Joseph, Beckers, Jean-François, Lange, Jean-Marie, Lebreton, P, De Oliveira, LA, ...

In mammals, thyrotropin, or thyroid-stimulating hormone (TSH), assay is used for the diagnosis of primary hypothyroidism. Hypothyroidism is the most common type of thyroid disorder in cattle. The aim...

Comparison of five radioimmunoassay systems for PAG measurement: Ability to detect early pregnancy in cows (2007)

Ayad, A, Melo De Sousa, Noelita, Sulon, Joseph, Iguer-Ouada, M, Beckers, Jean-François

This study was conducted to describe the minimum detection limit, reproducibility, accuracy, specificity and parallelism of different pregnancy-associated glycoprotein radioimmunoassay (PAG-RIA)...

Measurement of ovine pregnancy-associated glycoprotein (PAG) during early pregnancy in Lacaune sheep (2007)

El Amiri, B, Karen, A, Sulon, Joseph, Melo De Sousa, Noelita, Alvarez-Oxiley, A V, Cognié, Y, ...

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,...

Plasma concentrations of pregnancy-associated glycoprotein-1 (PAG-1) in high producing dairy cows suffering early fetal loss during the warm season (2007)

Lopez-Gatius, F, Hunter, RHF, Garbayo, JM, Santolaria, P, Yaniz, J, Serrano, B, ...

The present study was designed to establish whether plasma pregnancy-associated glycoprotein-1 (PAG-1) measurements during the early fetal period can be associated with early fetal loss. Blood...

Effect of the luteinizing hormone on embryo production in superovulated rabbit does (2007)

Salvetti, P, Theau-Clement, M, Beckers, Jean-François, Hurtaud, J, Guerin, P, Neto, V, ...

For most domestic animals, the responses to superovulation treatments are not controlled as a consequence of the lack of knowledge on exogenous gonadotrophins effects on the ovarian function. The...

Milk production correlates negatively with plasma levels of pregnancy-associated glycoprotein (PAG) during the early fetal period in high producing dairy cows with live fetuses (2007)

Lopez-Gatius, F, Garbayo, JM, Santolaria, P, Yaniz, J, Ayad, A, Melo De Sousa, Noelita, ...

This study was designed to establish possible factors affecting plasma pregnancy-associated glycoprotein (PAG) concentrations during early pregnancy in high producing dairy cows with live fetuses....

Influence of progesterone concentrations on secretory functions of trophoblast and pituitary during the first trimester of pregnancy in dairy cattle (2007)

Ayad, A, Melo De Sousa, Noelita, Sulon, Joseph, Hornick, Jean-Luc, Watts, J, Lopez-Gatius, F, ...

The essential role played by progesterone in the maintenance of pregnancy is unequivocal; however, the effects of progesterone on the secretory patterns of placental and pituitary molecules during...

Radioimmunoassay of bovine placental lactogen using recombinant and native preparations: determination of fetal concentrations across gestation (2007)

Alvarez-Oxiley, AV, Melo De Sousa, Noelita, Hornick, Jean-Luc, Touati, Kamal, Van Der Weijden, GC, Taverne, MAM, ...

Concentrations of bovine placental lactogen ( bPL) were determined in fetal plasma samples by twelve double-antibody competitive radioimmunoassay systems ( RIA I - XII) based on either recombinant...

Western analyses of pregnancy-associated glycoprotein family (PAG) in placental extracts of various mammals (2007)

Bella, A, Melo De Sousa, Noelita, Dehimi, ML, Watts, J, Beckers, Jean-François

The present study was conducted in order to analyze the inummoreactivity, of placental extracts of several animal species and humans against the following three groups of PAG antisera: anti-boPAG-1...

Plasma pregnancy-associated glycoprotein-1 (PAG-1) concentrations during gestation in Neospora-infected dairy cows. (2007)

Lopez-Gatius, F, Garbayo, J M, Santolaria, P, Yaniz, J L, Almeria, S, Ayad, A, ...

The aim of this study was to determine whether plasma pregnancy-associated glycoprotein-1 (PAG-1) concentrations in pregnancy are affected by persistent Neospora caninum infection in dairy cows. The...

Prolactin-induced activation of nuclear factor kappa B in bovine mammary epithelial cells: Role in chronic mastitis (2007)

Boutet, Philippe, Sulon, Joseph, Closset, R, Detilleux, J, Beckers, Jean-François, Bureau, Fabrice, ...

We sought to determine whether prolactin (PRL) could influence the neutrophilic inflammation that characterizes chronic mastitis. Most of the genes encoding inflammatory proteins depend on the...

Estrus synchronization, artificial insemination, and pregnancy diagnosis in water buffaloes (Bubalus bubalis) (2007)

Hanh, NV, Huu, QX, Uoc, NT, Nguyen, BX, Sulon, Joseph, Melo De Sousa, Noelita, ...

One of the big obstacles in management of reproductive activity in water buffaloes is their silent estrus. This characteristic prevents the determination of time for artificial insemination (AI),...

Protection against abortion linked to gamma interferon production in pregnant dairy cows naturally infected with Neospora caninum (2007)

Lopez-Gatius, F, Almeria, S, Donofrio, G, Nogareda, C, Garcia-Ispierto, I, Bech-Sabat, G, ...

Many immunological aspects of pregnancy, such as the role played by gamma interferon (IFN-gamma) in abortion, are not well understood. Neospora caninum is an intracellular protozoan considered to be...

Development of a radioimmunoassay for bovine chymosin B (2007)

Idrissa-Sidikou, Djibo, Remy, Benoit, Dufrasne, Isabelle, Cabaraux, Jean-François, Borceux, Jean-Philippe, Beckers, Jean-François

The present study was conducted to develop and validate a specific radioimmunoassay system for measurement of bovine chymosin B (bChyB) concentrations in plasma samples. Bovine ChyB was used for...

Comparison of accuracy of transabdominal ultrasonography, progesterone and pregnancy-associated glycoproteins tests for discrimination between single and multiple pregnancy in sheep (2006)

Karen, A, El Amiri, B, Beckers, Jean-François, Sulon, Joseph, Taverne, MAM, Szenci, O

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)...

Correlation between a proteolytic method and a radioimmunoassay for porcine serum pepsinogen concentrations (2006)

Sidikou, DI, Banga-Mboko, H, Tamboura, HH, Hornick, Jean-Luc, Remy, Benoit, Beckers, Jean-François

The measurement of serum pepsinogen concentrations by enzymatic method and immunoassay provides diagnostic values and should be helpful in the detection of gastric diseases related to a rise of blood...

Assessment of plasma profile of pregnancy-associated glycoprotein (PAG) in sheep with a heterologous (anti-caPAG(55+59)) RIA diagnosing and its potential for pregnancy (2006)

Ledezma-Torres, RA, Beckers, Jean-François, Holtz, W

The purpose of the present investigation was to generate pregnancy associated glycoprotein (PAG)-profiles throughout pregnancy in a heterogenous sample of sheep using a radioimmunoassay with a...

Clinical features and hormonal profiles of cloprostenol-induced early abortions in heifers monitored by ultrasonography (2006)

Lobago, Fikre, Gustafsson, Hans, Bekana, Merga, Beckers, Jean-François, Kindahl, Hans

Background: The present study describes the clinical features and plasma profiles of bovine pregnancy-associated glycoprotein 1 (bPAG1), the main metabolite of prostaglandin F2a (PG metabolite) and...

Evaluation of GnRH treatment 12 days after AI in the reproductive performance of dairy cows (2006)

Szenci, Otto, Takacs, Edit, Sulon, Joseph, Melo De Sousa, Noelita, Beckers, Jean-François

The objective of this study was to evaluate the effects of GnRH administered at Day 12 post-AI on the reproductive performance of dairy cows. Holstein-Friesian dairy cows (n = 103) on a large...

Pregnancy-Associated Glycoproteins (Pag) as Pregnancy Markers in the Ruminants (2006)

Melo De Sousa, Noelita, Ayad, A, Beckers, Jean-François, Gajewski, Z

In the last years, a polymorphic family of placenta-expressed proteins has been discovered in ruminant species and used for pregnancy diagnosis. Pregnancy diagnosis is an important part in...

Ultrasound fetal measurements and pregnancy associated glycoprotein secretion in early pregnancy in cattle recipients carrying somatic clones (2006)

Chavatte-Palmer, P, Melo De Sousa, Noelita, Laigre, P, Camous, S, Ponter, AA, Beckers, Jean-François, ...

Somatic cloning in the bovine species leads to high levels of fetal losses which occur throughout pregnancy. These losses are most often associated with fetal overgrowth, a syndrome known as large...

Variations in plasma matrix metalloproteinases and placental pregnancy-associated glycoproteins during gestation in rabbits (Oryctolagus cuniculus) (2006)

Othmani-Mecif, Khira, Benazzoug, Y, Jacob, MP, Beckers, Jean-François

Adaptation to pregnancy involves major maternal anatomical, physiological and metabolic modifications to support the mother's metabolic needs and those of the growing foetus. Invasion of embryonic...

The glycosylation of pregnancy-associated glycoproteins and prolactin-related protein-I in bovine binucleate trophoblast giant cells changes before parturition. (2006)

Klisch, Karl, Boos, A, Friedrich, M, Herzog, K, Feldmann, M, Melo De Sousa, Noelita, ...

Binucleate trophoblast giant cells (BNC) in the bovine placenta produce glycoproteins, which are delivered into the mother after fusion of BNC with uterine epithelial cells. During most time of...

Endocrinology of pregnancy in the cow: embryonic signals, placental hormones and proteins (2006)

Ayad, A, Melo De Sousa, Noelita, Hornick, Jean-Luc, Touati, Kamal, Iguer-Ouada, M, Beckers, Jean-François

The development, the establishment and the embryonic survival at early stages of gestation are depending on an intimate dialogue between the embryo and his mother. For the embryo part, it is...

Improved vitrification method allowing direct transfer of goat embryos (2006)

Guignot, F, Bouttier, A, Baril, G, Salvetti, P, Pignon, P, Beckers, Jean-François, ...

The aim of this study was to design a vitrification method suited to field embryo transfer experiments in goat. In a first experiment, a standard vitrification protocol, previously designed for sheep...

Pregnancy associated glycoproteins (PAG) in postpartum cows, ewes, goats and their offspring (2006)

Haugejorden, G, Waage, S, Dahl, E, Karlberg, K, Beckers, Jean-François, Ropstad, E

Determination of plasma concentrations of pregnancy associated glycoproteins (PAG) has been used for early pregnancy diagnosis in cows. However, this is complicated by the presence of PAG in plasma...

Endocrinology of pregnancy and early pregnancy detection by reproductive hormones in reindeer (Rangifer tarandus tarandus) (2005)

Ropstad, E, Veiberg, V, Sakkinen, H, Dahl, E, Kindahl, H, Holand, O, ...

The endocrinology was studied throughout pregnancy in reindeer (Rangifer tarandus tarandus) located in Oulu, Finland (65 degrees N, 25 degrees E) with 13 captive, semi domestic adult females. Blood...

Pregnancy associated glycoprotein-1,-6,-7, and-17 are major products of bovine binucleate trophoblast giant cells at midpregnancy (2005)

Klisch, K, Melo De Sousa, Noelita, Beckers, Jean-François, Leiser, R, Pich, A

Pregnancy associated glycoproteins (PAGs) are extensively glycosylated secretory proteins of ruminant trophoblast cells. In cattle placenta several PAG cDNAs are expressed, but the variety of...

Bovine pepsinogen and Prochymosin : Current knowledge, applications and outlines in the management of gastrointestinal worms (2005)

Sidikou, ID, Remy, B, Hornick, Jean-Luc, Losson, Bertrand, Duquesnoy, Natacha, Yenikoye, A, ...

The characterization of the gastric aspartic proteases and the understanding of their mechanisms of activation led to several applications in many domains as the use of chymosin in cheese industries...

Use of a homologous radioimmunoassay (RIA) to evaluate the effect of maternal and foetal parameters on pregnancy-associated glycoprotein (PAG) concentrations in sheep (2005)

Vandaele, Leen, Verberckmoes, S, El Amiri, Bouchra, Sulon, Joseph, Duchateau, L, Van Soom, Ann, ...

Early pregnancy detection and prediction of the number of lambs would be profitable for sheep breeders because it enables them to adjust nourishment of pregnant ewes according to the individual needs...

Plasma concentrations of bovine pregnancy-associated glycoprotein (bPAG) do not differ during the first 119 days between ongoing pregnancies derived by transfer of in vivo and in vitro produced embryos (2005)

Breukelman, SP, Perenyi, Z, De Ruigh, L, Jonker, FH, Vernooij, JCM, ...

Calves derived from IVP embryos may suffer from the large offspring syndrome that has been related to effects of in vitro culture on the intrinsic quality of the embryo. Limited information is...

Development of a Radioimmunoassay for Bovine Pepsinogen A (2005)

Sidikou, ID, Remy, B, Beckers, Jean-François

Pepsinogen A is the most abundant zymogen found in blood, and its enzymatic measurement is used for the diagnosis of gastric lesions. The present study was conducted to develop a radioimmunoassay...

Effect of the type and number of prostaglandin treatments on corpus luteum, the largest follicle and progesterone concentration in dairy cows (2005)

Repasi, A, Beckers, Jean-François, Sulon, Joseph, Karen, Aly, Reiczigel, J, Szenci, Otto

Lactating dairy cows (n = 72) with a mature corpus luteum (CL) (diameter of >= 17 mm) determined by ultrasonography and having a follicle with a diameter of >= 10 min were randomly assigned to four...

Chorionic mRNA expression and N-glycodiversity of pregnancy-associated glycoprotein family (PAG) of the European bison (Bison bonasus) (2005)

Szafranska, Bozena, Panasiewicz, G, Dabrowski, M, Majewska, M, Gizejewski, Z, Beckers, Jean-François

Placental PAG mRNA expression and N-glycodiversity of multiple PAG proteins secreted in vitro by trophectoderm (chorion epithelium) of wild pecoran Bovidae taxons was not examined previously. The...

A new test for early pregnancy diagnosis in sheep: Determination of ovine pregnancy associated glycoprotein (ovPAG) concentration by means of a homologous radioimmunoassay (2004)

Verberckmoes, S, Vandaele, Leen, De Cat, S, El Amiri, B, Sulon, Joseph, Duchateau, L, ...

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...

Isolation and characterization of eight pregnancy-associated glycoproteins present at high levels in the ovine placenta between day 60 and day 100 of gestation (2004)

El Amiri, B, Remy, Benoit, Melo De Sousa, Noelita, Beckers, Jean-François

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...

A comparison of diagnosis of pregnancy in the goat via transrectal ultrasound scanning, progesterone, and pregnancy-associated glycoprotein assays (2004)

Gonzalez, Fernando, Cabrera, F, Batista, M, Rodriguez, N, Alamo, D, Sulon, Joseph, ...

Real-time ultrasound scanning (US) via the transrectal route, progesterone (P4) assay, and pregnancy-associated glycoprotein (PAG) detection can be used to diagnose pregnancy at around 3 weeks after...

Accuracy of transrectal ultrasonography for determination of pregnancy in sheep: effect of fasting and handling of the animals (2004)

Karen, Aly, Szabados, K, Reiczigel, J, Beckers, Jean-François, Szenci, Otto

The present study was performed to investigate the effect of previous fasting and lifting of the abdomen of the ewes during transrectal ultrasonographic scanning on the results of early pregnancy...

Endocrine profiles, haematology and pregnancy outcomes of late pregnant Holstein dairy heifers sired by bulls giving a high or low incidence of stillbirth (2004)

Kornmatitsuk, B, Dahl, E, Ropstad, E, Beckers, Jean-François, Gustafsson, HG, Kindahl, H

The high incidence of stillbirth in Swedish Holstein heifers has increased continuously during the last 15 years to an average of 11% today. The pathological reasons behind the increased incidence of...

Fetometry and fetal heart rates between Day 35 and 108 in bovine pregnancies resulting from transfer of either MOET, IVP-co-culture or IVP-SOF embryos (2004)

Breukelman, SP, Reinders, JMC, Jonker, FH, De Ruigh, L, Kaal, LMTE, ...

The Large Offspring Syndrome has frequently been reported for in vitro produced calves. The objective of this study was to determine whether any differences in body dimensions (biparietal diameter of...

Immune response and antigen recognition in non-pregnant ewes experimentally infected with Neospora caninum tachyzoites (2004)

Rettigner, Chantal, Lasri, S, De Meerschman, F, Focant, C, Beckers, Jean-François, Losson, Bertrand

The cellular and humoral responses as well as the antigen recognition during the acute stage of a Neospora caninum (NC) infection were investigated in non-pregnant ewes. The experimentally infected...

Ultrasonography in early pregnancy diagnosis and measurements of fetal size in reindeer (Rangifer tarandus tarandus) (2004)

Vahtiala, S, Sakkinen, H, Dahl, E, Eloranta, E, Beckers, Jean-François, Ropstad, E

Transrectal or transabdominal examinations of 13 pluriparous reindeer (Rangifer tarandus tarandus) by ultrasonography from the start of mating until week 20 of gestation were conducted to find out...

Survey of gastric lesions and blood pepsinogen levels in pigs in Burkina Faso (2003)

Banga-Mboko, Henri, Tamboura, Hamidou, Maes, D, Traore, H, Youssao, I, Sangild, PT, ...

The purpose of the study was to investigate the prevalence of gastric lesions and to provide diagnostic values for serum pepsinogen in non-infected pigs and in pigs with gastric disease. In an...

An improved radioimmunoassay for measurement of pepsinogen in porcine blood samples (2003)

Banga-Mboko, Henri, Sulon, Joseph, Lange, JM, Remy, Benoit, Youssao, I, Melo De Sousa, Noelita, ...

The study was conducted to develop a sensitive and specific radioimmunoassay (RIA) for the measurement of pepsinogen in porcine serum, and to use this test for the determination of pepsinogen...

Early pregnancy diagnosis in sheep by progesterone and pregnancy-associated glycoprotein tests (2003)

Karen, A, Beckers, Jean-François, Sulon, Joseph, Melo De Sousa, Noelita, Szabados, K, Reczigel, J, ...

The aim of this study was to compare the accuracy of the progesterone (P4) and pregnancy associated glycoprotein (PAG) tests for determination of early pregnancy in sheep. Estrus was synchronized in...

The use of blood pepsinogen as a biomarker of the integrity of the porcine gastric mucosa. 2. Measurements of blood pepsinogen and its usefull in the detection of gastric diseases (2003)

Banga-Mboko, Henri, Godeau, Jean-Marie, Drion, Pierre, Sidikou, ID, Remy, Benoit, Beckers, Jean-François

Pepsinogen is one component of the gastric juice which participes in the digestion. This macromolecule enters the blood circulation in a small measurable quantities in healthy subjects. Therefore,...

Evaluation of false transrectal ultrasonographic pregnancy diagnoses in sheep by measuring the plasma level of pregnancy-associated glycoproteins (2003)

Karen, A, Beckers, Jean-François, Sulon, Joseph, El Amiri, B, Szabados, K, Ismail, S, ...

The present study was undertaken to investigate to what extent pregnancy diagnoses made by transrectal ultrasonography could be confirmed by measurements of plasma concentration of ovine...

Chorionic expression of heterogeneous products of the PAG (Pregnancy-Associated Glycoprotein) gene family secreted in vitro throughout embryonic and foetal development in the pig (2003)

Szafranska, B, Panasiewicz, G, Majewska, M, Beckers, Jean-François

Porcine PAG (pPAG) are placental products of a multigene family that is strongly expressed in the chorionic epithelium (trophoblast and trophectoderm). The objective of this study was to define a...

Development and validation of a specific radioimmunoassay for equine osteocalcin (2003)

Carstanjen, Bianca, Sulon, Joseph, Banga-Mboko, H, Beckers, Jean-François, Remy, Benoit

This study describes for the first time the development and validation of a sensitive and specific radioimmunoassay (RIA) for equine osteocalcin (OC) quantification using purified equine OC as...

Diagnosis and monitoring of pregnancy in sheep: reality and perspectives (2003)

El Amiri, Bouchra, Karen, Aly, Cognié, Yves, Melo De Sousa, Noelita, Hornick, Jean-Luc, Szenci, Otto, ...

The present review aims at presenting different methods for pregnancy diagnosis. Since these methods are to be used in the herds, precocity, sensitivity, specificity, accuracy to predict pregnant and...

Double radial immunodiffusion as a tool to identify pregnancy-associated glycoproteins in ruminant and nonruminant placentae (2003)

El Amiri, B, Melo De Sousa, Noelita, Mecif, K, Desbuleux, H, Banga-Mboko, H, Beckers, Jean-François

Pregnancy-associated glycoproteins (PAGs) are antigens synthesized in the superficial layers of the ruminant trophoblast. Initially, they were identified either as proteins released into the maternal...

Effect of different doses of prostaglandin on the area of corpus luteum, the largest follicle and progesterone concentration in the dairy cow (2003)

Repasi, A, Beckers, Jean-François, Sulon, Joseph, Perenyi, Z, Reiczigel, J, Szenci, Otto

Lactating dairy cows with a mature corpus luteum (CL) (diameter of greater than or equal to17 mm determined by ultrasonography) and having a follicle with a diameter of 10 mm (n = 49) were randomly...

Effect of induction of late embryonic mortality on plasma profiles of pregnancy associated glycoprotein 1 in heifers (2003)

Szenci, Otto, Beckers, Jean-François, Sulon, Joseph, Bevers, MM, Borzsonyi, L, Fodor, L, ...

Inoculation with Actinomyces pyogenes and administration of prostaglandin (PG) F-2alpha were used to induce late embryonic mortality (LEM) in heifers (n = 8) on Days 30-38 of pregnancy in order to...

Effect of plasma urea-N concentration on fertility in a Holstein-Friesian dairy herd (2003)

Szenci, Otto, Simonsen, I, Bajcsy, CA, Perenyi, Z, Karen, Aly, Sulon, Joseph, ...

The objectives of this study were to relate the concentrations of plasma urea nitrogen (UN) to pregnancy rate in dairy cows. The cows were grouped, according to their production level and feed...

Isolation and partial characterization of three pregnancy-associated glycoproteins from the ewe placenta (2003)

El Amiri, B, Remy, Benoit, Melo De Sousa, Noelita, Joris, Bernard, Otthiers, Nicole, Perenyi, Z, ...

Pregnancy-associated glycoproteins (PAGs) are synthesized in the outer epithelial layer of the placenta in artiodactyls. In this work, three novel ovine PAGs were isolated from late-pregnancy fetal...

Pregnancy-associated glycoprotein concentrations during pregnancy and the postpartum period in Azawak Zebu cattle (2003)

Melo De Sousa, Noelita, Zongo, M, Pitala, W, Boly, Hamidou, Sawadogo, L, Sanon, M, ...

Specific RIA systems were developed and used to measure pregnancy-associated glycoprotein (PAG) concentrations during gestation and the postpartum period in Azawak Zebu cows. Twelve females were...

From the germinal cells to the newborn animal: The transmission of genes and life through the generations (2003)

Drion, Pierre, Szenci, Otto, Ectors, Fabien, Wirth, D, Perenyi, Z, Muller, P, ...

The technology of reproduction progressed considerably during the last decade, leading to a certain availability of in vitro methods for fertilisation, oocyte maturation and embryo culture. The most...

Physiology of reproduction and endocrinology in cervids. A review (2003)

Drion, Pierre, Hanzen, Christian, Wirth, Delphine - In Memoriam, Beckers, Jean-François, Leboeuf, Bernard, Ropstad, Eric, ...

Knowledge about cervids are rapidly growing. This work aims to present the more recent scientific information on reproductive physiology and endocrinology of the cervids: anatomy of the genital...

Application des prostaglandines en reproduction des espèces moins fréquentes ou de laboratoires: Souris, Rat, Hamster, Gerbille, Cobaye, Furet, Cervidés, Buffalos, Zebu, Bison (2003)

Drion, Pierre, Hanzen, Christian, Wirth, Delphine, Leboeuf, Bernard, Beckers, Jean-François

En l'an 300 avant notre ère, Herophilus d'Alexandrie fut le premier qui reconnut les ovaires comme entités propres à la femelle de la même manière que les testicules sont des attributs propres...

Signaux embryonnaires de la gestation (2002)

Sousa, N, El Amiri, B, Remy, Benoit, Drion, Pierre, Beckers, Jean-François

European Convention of the French Buiatric Society - Journées Européennes de la Société Française de Buiatrie

The use of blood pepsinogen as a biomarker of the integrity of the porcine gastric mucosa : A review. Part 1: History, physiopathology of gastric mucosa and different forms of pepsinogens (2002)

Banga-Mboko, Henri, Godeau, Jean-Marie, Drion, Pierre, El Amiri, Bouchra, Drion, Pierre, Perenyi, Zsolt, ...

Because the history is defined as the account of the passed events, this manuscript is an Update research on swine pepsinogens since their discovery by Theodor Schwann. Progress was particularly made...

Aspartic proteinase members secreted by the ruminant placenta: Specificity of three radioimmunoassay systems for the measurement of pregnancy-associated glycoproteins (2002)

Perenyi, ZS, Szenci, O, Drion, Pierre, Banga-Mboko, H, Sousa, NM, El Amiri, Bouchra, ...

Pregnancy-associated glycoproteins (PAGs) isolated from the placenta of various ruminant species are enzymatically inactive members of the aspartic proteinase family. The measurement of these...

Characterization of pregnancy-associated glycoproteins extracted from zebu (Bos indicus) placentas removed at different gestational periods (2002)

Melo De Sousa, Noelita, Remy, Benoit, El Amiri, Bouchra, De Figueiredo, JR, Banga-Mboko, Henri, Goncalves, PBD, ...

In the present work, two biochemical approaches were used to characterize PAGs isolated from Bos indicus fetal cotyledons removed at different gestational ages. The first procedure included acidic...

Comparison of the ability of three radioimmunoassay to detect pregnancy-associated glycoproteins in bovine plasma (2002)

Perenyi, ZS, Szenci, Otto, Sulon, Joseph, Drion, Pierre, Beckers, Jean-François

Pregnancy-associated glycoproteins (PAGs) constitute a large family of glycoproteins that are synthesized in the superficial layer of the ruminant placenta according to a spatial and temporal...

Hormonal measurements in late pregnancy and parturition in dairy cows - possible tools to monitor foetal well being (2002)

Kornmatitsuk, B, Veronesi, MC, Madej, A, Dahl, Ellen, Ropstad, E, Beckers, Jean-François, ...

Three dairy heifers (A, B and C) were induced to parturition with two prostaglandin (PG) F-2alpha injections on day 268 and 269 of pregnancy. Signs of approaching parturition were carefully observed....

Potential influence of pregnancy hormones and proteins synthesized during pregnancy on the maternal immunological status (2002)

Melo De Sousa, Noelita, Figueiredo, JR, El Amiri, Bouchra, Banga-Mboko, Henri, Beckers, Jean-François

During pregnancy, the endocrine function of the gonads and the foeto-placental unit involves the synthesis of several hormones (progesterone, oestrogens, cortisol, prostaglandins, prolactin,...

Plasma profile of pregnancy associated glycoprotein (PAG) in pregnant Alpine goats using two radioimmunoassay (RIA) systems (2001)

Batalha, ES, Sulon, Joseph, Figueiredo, JR, Beckers, Jean-François, Espeschit, CJB, Martins, R, ...

This paper evaluates the profiles obtained for caprine pregnancy associated glycoprotein (cPAG) in pregnant multiparous and nulliparous goats using the heterologous-radioimmunoassay (htPAG-RIA) and...

Relationship between maternal concentrations of caprine pregnancy-associated glycoprotein in Alpine goats and the number of fetuses using a homologous radioimmunoassay (2001)

Batalha, ES, Sulon, Joseph, Figueiredo, JR, Beckers, Jean-François, Martins, GA, Silva, LDM

The relationship between maternal caprine pregnancy-associated glycoprotein (cPAG) concentrations and fetal number was investigated in 21 nulliparous and 17 multiparous goats. Using a homologous...

Artificial induction of lactation in heifers aged from 6 to 7 months (2001)

Nchare, A, Salaheddine, M, Desbuleux, H, Sulon, Joseph, Beckers, Jean-François

The rates of successful gene's manipulations are very low in domestic mammals. In addition the period between generations in cows is long. Artificial induction of lactation in young animals could...

Four years of induction/synchronization of estrus in dairy goats: effect on the evolution of eCG binding rate in relation with the parameters of reproduction (2001)

Drion, Pierre, Furtoss, V, Baril, G, Manfredi, E, Bouvier, F, Pougnard, JL, ...

Ninety-eight Alpine goats of two herds were followed over 4 years in a program of annual artificial insemination after estrus induction/synchronization, including progestagen administration (vaginal...

Increase of Plasma Ecg Binding Rate after Administration of Repeated High Dose of Ecg to Cows (2001)

Drion, Pierre, De Roover, R, Houtain, J Y, McNamara, E M, Remy, Benoit, Sulon, Joseph, ...

Equine chorionic gonadotrophin (eCG) is still used to promote follicular growth in cattle and, more recently with an increased frequency of administration, in ovum pick-up protocols. The aim of this...

Immunocytochemistry of the golden hamster pituitary during chronic administration of diethylstilbestrol: a quantitative analysis using laser scanning microscopy (2001)

Van Cauwenberge, A, Nonclercq, D, Laurent, G, Zanen, G, Beckers, Jean-François, Alexandre, H, ...

The aim of this study was to examine by immunohistochemistry the morphologic changes affecting pituitary cell populations in male Syrian hamsters undergoing chronic exposure (3 days to 9 months) to...

Caractéristiques de la reproduction dans l’espèce caprine (2001)

Zarrouk, A, Souilem, O, Drion, Pierre, Beckers, Jean-François

This review pointed out the physiological basis of goat reproduction. So far assimilated to ewes, goats presented their own characteristics concerning the sexual activity and the endocrinology of...

Placental proteins in ruminants: biochemical, physiological and zootechnical aspects (2001)

Melo De Sousa, Noelita, Figueiredo, JR, Beckers, Jean-François

During the last decade, investigations were carried out by several research groups in order to characterize proteins or glycoproteins synthesized in the ruminant placenta. Recently, as results of...

Study of the Virulence of Five Strains of Amyxomatous Myxoma Virus in Crossbred New Zealand White/Californian Conventional Rabbits, with Evidence of Long-Term Testicular Infection in Recovered Animals (2000)

Marlier, Didier, Mainil, Jacques, Sulon, Joseph, Beckers, Jean-François, Linden, Annick, Vindevogel, Henri

The virulence of five amyxomatous myxoma virus (MV) strains, the clinical and pathogenetic effects of which had been studied previously in specific pathogen-free (SPF) rabbits, was determined by...

Inflammatory Effect of Intratracheal Instillation of Ultrafine Particles in the Rabbit: Role of C-Fiber and Mast Cells (1999)

Nemmar, A, Delaunois, Annie, Nemery, B, Dessy-Doize, C, Beckers, Jean-François, Sulon, Joseph, ...

The effects of ultrafine polystyrene carboxylate-modified (fluorospheres) on inflammatory processes are being investigated in rabbit lungs. One milliliter of sterile NaCl (0.9%) containing 4 mg of...

Pregnancy-Associated Glycoprotein Levels in Pregnant Goats Inoculated with Toxoplasma Gondii or Listeria Monocytogenes: A Retrospective Study (1999)

Zarrouk, A, Engeland, IV, Sulon, Joseph, Beckers, Jean-François

The pregnancy-associated glycoprotein (PAG) concentration profiles of goats that had been experimentally inoculated with either Toxoplasma gondii or Listeria monocytogenes are described. All goats...

Determination of Pregnancy-Associated Glycoprotein Concentrations in Goats (Capra Hircus) with Unsuccessful Pregnancies: A Retrospective Study (1999)

Zarrouk, A, Engeland, I, Sulon, Joseph, Beckers, Jean-François

Presented here are the profiles of pregnancy-associated glycoprotein (PAG) concentrations in blood collected weekly from goats experiencing maintained and unsuccessful pregnancies. The analysis of...

Modulatory Effect of Imetit, a Histamine H3 Receptor Agonist, on C-Fibers, Cholinergic Fibers and Mast Cells in Rabbit Lungs in Vitro (1999)

Nemmar, A, Delaunois, Annie, Beckers, Jean-François, Sulon, Joseph, Bloden, Serge, Gustin, Pascal

The pharmacological mechanisms involved in the interactions between C-fibers, cholinergic fibers and mast cells were investigated in tracheally perfused rabbit lungs by measuring the simultaneous...

Pregnancy-associated glycoprotein and decreased polymorphonuclear leukocyte function in early post-partum dairy cows (1999)

Dosogne, H, Burvenich, Christian, Freeman, AE, Kehrli, Jr, Detilleux, JC, Sulon, Joseph, ...

Phagocytosis and oxidative burst activity of polymorphonuclear neutrophil leukocytes (PMN) isolated from blood and pregnancy-associated glycoprotein (bPAG) concentrations in plasma were evaluated in...

Postepy Biologii Komorki (1999)

Gajewski, Zdzislaw, Beckers, Jean-François, Melo De Sousa, Noelita, Thun, Rico, Sulon, Joseph, Faundez, Ricardo

This study is carried out to determine ovine pregnancy associated glycoprotein (oPAG) levels in the serum of Berrichone ewes throughout gestation and the first month post partum. The levels were...

Pregnancy Associated Glycoproteins in Ruminants: Inactive Members of the Aspartic Proteinase Family (1999)

Beckers, Jean-François, Drion, Pierre, Garbayo, JM, Perenyi, Z, Zarrouk, A, Sulon, Joseph, ...

The Pregnancy Associated Glycoproteins (PAGs) presented in this paper are largely expressed in the ruminant placenta. These proteins are classified as probably inactive members of the aspartic...

Postepy Biologii Komorki (1999)

Gajewski, Zdzislaw, Beckers, Jean-François, Melo De Sousa, Noelita, Thun, Rico, Sulon, Joseph, Faundez, Ricardo

This study is carried out to determine ovine pregnancy associated glycoprotein (oPAG) levels in the serum of Berrichone ewes throughout gestation and the first month post partum. The levels were...

Endocrinology of pregnancy: chorionic somatomammotropins and pregnancy-associated glycoproteins: review (1998)

Beckers, Jean-François, Zarrouk, Anissa, Batalha, Evie S, Garbayo, José-Maria, Mester, L, Szenci, Otto

The two main groups of placental proteins of ruminants are discussed in this paper: chorionic somatomammotropins (placental lactogens) and pregnancy-specific (-associated) proteins. Placental...

Comparison of ultrasonography, bovine pregnancy specific B, and bovine pregnancy-associated glycoprotein 1 test for pregnancy detection in dairy cows (1998)

Szenci, Otto, Beckers, Jean-François, Humblot, Patrice, Sulon, Joseph, Sasser, G, Taverne, Marcel, ...

At Days 26 to 58 after AI, 138 Holstein-Friesian dairy cows were repeatedly examined by ultrasonography, using a 7.5 MHz linear-array rectal transducer. The total calving rate was 37.6% (52/138), and...

Endocrinologie de la gestation chez les ruminants: les protéines placentaires (1998)

Zarrouk, Anissa, Remy, Benoît, Sulon, Joseph, Drion, Pierre, Desbuleux, Henri, Beckers, Jean-François

The two main groups of placental proteins of ruminants are related in this paper: Placental lactogens and Pregnancy-Specific (-Associated) Proteins. Placental lactogens belong to the prolactin and...

Radioimmunoassay of Substance P in Lung Perfusate (1998)

Nemmar, A, Gustin, Pascal, Delaunois, A, Beckers, Jean-François, Sulon, Joseph

A radioimmunoassay of the undecapeptide substance P (SP) and its application in rabbit lung superfusate has been developed. The assay was based on the use of a radioactive tracer, 125I-SP-Tyr8, which...

Isolation and partial characterization of a pregnancy-associated glycoprotein (PAG) family from the goat placenta (1998)

Garbayo, Juana Maria, Remy, Benoit, Alabart, José Luis, Folch, José, Wattiez, Ruddy, Beckers, Jean-François

Antigen(s) immunologically related to pregnancy-associated glycoproteins (PAGs) have previously been detected in the serum of pregnant goats. In this work, we describe a partial characterization of a...

Isolation and Partial Characterization of a Pregnancy-Associated Glycoprotein Family from the Goat Placenta (1998)

Garbayo, JM, Remy, Benoit, Alabart, JL, Folch, J, Wattiez, R, Falmagne, P, ...

Antigen(s) immunologically related to pregnancy-associated glycoproteins (PAGs) have previously been detected in the serum of pregnant goats. In this work, we describe a partial characterization of a...

Evaluation of false ultrasonographic pregnancy diagnoses in cows by measuring plasma levels of bovine pregnancy-associated glycoprotein 1 (bPAG1). (1998)

Szenci, Otto, Taverne, M.A.M., Beckers, Jean-François, Sulon, Joseph, Varga, J, Bözsönyi, L, ...

Between days 27 and 59 after artificial insemination (AI),189 ultrasonographic pregnancy diagnoses were made in 56 dairy cows using a 7·5 MHz linear-array rectal transducer. Blood samples were...

Utilisation répétée des gonadotropines exogènes dans le contrôle de la reproduction: justifications et effets secondaires potentiels (1998)

Drion, Pierre, Houtain, Jean-Yves, MC Namara, M, Baril, Gérard, Heyman, Yvan, Cognié, Yves, ...

Gonadotropins of pituitary origin (follitropin -FSH-, lutropin -LH-, human menopausal gonadotropin -hMG) or trophoblastic origin (human chorionic gonadotropin - hCG- also called pregnant urine...

Radioimmunoassay of substance P in lung perfusate. (1998)

Nemmar, A, Gustin, Pascal, Delaunois, Annie, Sulon, J, Beckers, Jean-François

A radioimmunoassay of the undecapeptide substance P (SP) and its application in rabbit lung superfusate has been developed. The assay was based on the use of a radioactive tracer, 125I-SP-Tyr8, which...

In vivo and in vitro development of preantral follicles (1997)

Bevers, M.M., Beckers, Jean-François

The paper presents the state of the art concerning the in vitro growth and differentiation of preantral follicles, i.e. from the primordial to the antral stage, in mammals. Attention is paid to their...

Protéinas placentárias em mamíferos (1997)

Melo De Sousa, Noelita, De Figueiredo, José Ricardo, Gonçalves, Paulo Bayard Dias, Beckers, Jean-François

During the past twenty years, several new placental proteins have been isolated and characterized in woman and several animal species. Among these proteins, it can be mentioned chorionic...

Le clonage par transfert de noyau dans l'espèce bovine (1997)

Ectors, Fabien, Delval, Alain, Beckers, Jean-François, Drion, Pierre, Remy, Benoit, Ectors, Francis

A all in vitro cloning technique was developed in wich embryos from the first cycle nuclear transfer (cloning) were used as blastomere donor for the second cycle nuclear transfer (re-cloning). Such...

Plasma pregnancy-associated glycoprotein and progesterone concentrations in pregnant Assaff ewes carrying single and twin lambs (1997)

Ranilla, Marie-José, Sulon, Joseph, Mantecón, A.R., Beckers, Jean-François, Carro, M.D.

Ovine pregnancy-associated glycoprotein (oPAG) and progesterone (P4) concentrations were monitored weekly during the last three months of gestation and the first month postpartum in plasma of twelve...

Bovine preantral follicles and activin: immunohistochemistry for activin and activin receptor and the effect of bovine activin A in vitro (1997)

Hulshof, S.C.J., Figueiredo, J.R., Beckers, Jean-François, Bevers, M.M., Vanderstichele, H.

Activin was originally isolated from follicular fluid as a factor stimulating FSH from the pituitary. Recent studies also suggest a local role for activin in the development of preantral and early...

Non délivrance et infécondité: intérêts de l’étiproston et du dosage de la PAGI (pregnancy-associated glycoprotein I) au cours du postpartum chez la vache. (1997)

Zaiem, I, Tainturier, D, Ben Othmen, H, Beckers, Jean-François, Chemli, J

Sixty Prim'holstein cows with retained placenta for more than 24 hours after parturition, were shared in three groups of 20 cows each. All cows were delivred manually 24 to 36 hours post partum and...

Plasma bovine pregnancy-associated glycoprotein concentrations throughout gestation in relationship fetal number in the cow (1997)

Patel, Osman V, Sulon, Joseph, Beckers, Jean-François, Takahashi, Toru, Hirako, Makoto, Sasaki, Nobuo, ...

This study characterized the peripheral plasma bovine pregnancy-associated glycoprotein (bPAG) profile throughout gestation and examined the effect of stage of gestation and fetal number on this...

Anti-PMSG in sheep subjected annualy to oestrus synchronisation (1997)

Bodin, L, Drion, Pierre, Remy, Benoit, Brice, G, Cognié, Yves, Beckers, Jean-François

Estimation of the long-term consequences on reproduction performance of the oestrus synchronisation treatments that are annually applied to ewes was carried out on nine officially controlled dairy...

Multiple pregnancy-associated glycoproteins are secreted by day 100 sheep placenta (1997)

Xie, Sancai, Green, Jonathan, Bao, Bagna, Beckers, Jean-François, Valdez, Kelli E, Hakami, Livija, ...

Pregnancy-associated glycoprotein (PAG)-1 (PAG1) and pregnancy-specific protein B are either identical or closely related antigens released by trophoblast binucleate cells of placentas of cattle....

Regolazione della crescité follicolare e luteinica. Ovulazione, corpo luteo e luteolisi (1997)

Drion, Pierre-Vincent, Ectors, Fabien, Hanzen, Christian, Houtain, Jean-Yves, Lonergan, P, Beckers, Jean-François

Most ovarian follicles (99.9%) will end up with follicular atresia. During antral stages atresia depends on a reduction of FSH levels secondary to estradiol and inhibin secretions by the dominant...

Regolazione della crescité follicolare et luteinica. Folliculogenesi e atresia. Summa (1997)

Drion, Pierre, Beckers, Jean-François, Ectors, Fabien, Hanzen, Christian, Houtain, Jean-Yves, Lonergan, P

Hypophyseal production of FSH and LH depends on a pulsating secretion of GnRH by the Hypothalamus. At the beginning of the cycle, this secretion sets free the FSH from the hypothesis responsible for...

Pregnancies, calves and calf viability after transfer of in vitro produced bovine embryos (1996)

Schmidt, T, Greve, T, Avery, B, Beckers, Jean-François, Sulon, Joseph, Hansen, HB

Pregnancy, parturition and calf survival following the transfer of embryos produced in vitro were monitored. A total of 44 blastocysts was transferred in pairs to 1 uterine horn ipsilateral to the...

Synchronization of estrus in goats: the relationship between PMSG binding in plasma, time of occurrence of estrus and fertility following artificial insemination (1996)

Baril, G, Remy, Benoît, Leboeuf, JF, Beckers, Jean-François, Saumande, J

Radioimmunoassay (RIA) was used to measure plasma eCG binding in dairy goats (n = 524) at the beginning of a progestagen/eCG treatment and 25 d after eCG administration. The eCG binding was not...

Trophoblast-specific processing and phosphorylaton of pregnancy-associated glycoprotein-1 in day 15 to 25 sheep placenta (1996)

Xie, S, Nagel, RJ, Green, J, Beckers, Jean-François, Roberts, RM

Bovine and ovine pregnancy-associated glycoproteins-1 (PAG-1) are products of binucleate trophoblast cells and belong to the aspartic proteinase gene family. Estimates of their relative molecular...

In situ demonstration of germinal cell apoptosis during diethylstilbestrol-induced testis regression in adult male syrian hamsters (1996)

Nonclercq, D, Reverse, D, Toubeau, G, Beckers, Jean-François, Sulon, Joseph, Laurent, G, ...

Testis regression was induced in male Syrian hamsters by chronic exposure to diethylstilbestrol (DES), an estradiol-1713 agonist. Experimental groups (n = 4-5) were killed at increasing time...

Glycoproteins of the aspartyl proteinase gene family secreted by the developing placenta (1995)

Roberts, RM, Xie, S, Nagel, RJ, Low, B, Green, J, Beckers, Jean-François

Pregnancy in cattle and sheep can be diagnosed by the presence of placentally-derived antigens (pregnancy-associated glycoproteins or PAG-1) in maternal serum soon after implantation begins at about...

Cytogenetic study of bovine oocytes matured in vitro (1995)

Ectors, Fabien, Koulischer, Lucien, Jamar, M, Herens, C, Verloes, A, Remy, Benoît, ...

Described in the present paper is a cytogenetic study of bovine oocytes matured in vitro. The cumulus-oocyte complexes (COC), punctured from ovaries recovered in a local slaughterhouse, were...

Fractionation and partial characterization of proteins extracted from the bovine fallopian tube: preparation of tools for further purifications (1995)

Remy, Benoît, Rabahi, F, Duwez, L, Thonon, F, Ectors, Francis, Ectors, Fabien, ...

Described in the present paper is a combined biochemical and immunological approach to study oviductal proteins in the bovine. Antisera were raised against semi-purified proteins extracted from...

Effects of fetal bovine serum, FSH and 17ß-Estradiol on the culture of bovine preantral follicles (1995)

Hulshof, SCJ, Figueiredo, JR, Beckers, Jean-François, Bevers, MM

We describe a 7-d culture in droplets of collagen gel of isolated small bovine preantral follicles in medium with or without 10% fetal bovine serum (FBS). In addition, the effect of human recombinant...

The gene encoding bovine pregnancy-associated glycoprotein-1, an inactive member of the aspartic proteinase family (1995)

Xie, S, Green, J, Beckers, Jean-François, Roberts, RM

Bovine pregnancy-associated glycoprotein 1 (bPAG1) is a member of the aspartic proteinase family. It becomes detectable in maternal serum soon after implantation and is produced specifically in the...

Extracellular matrix proteins and basement membrane identification in bovine ovaries and significance for the attachment of cultured preantral follicles (1995)

Figueiredo, JR, Hulshof, SCJ, Thiry, M, Bevers, MM, Nusgens, B, ...

Described in the present paper is the immunolocalization of the extracellular matrix proteins (e.g., fibronectin, collagen Types I and III) in the bovine ovary, with special attention to preantral...

Superovulation of goats with purified pFSH supplemented with defined amounts of pLH (1995)

Nowshari, MA, Beckers, Jean-François, Holtz, W

The superovulatory response of goats treated with purified pFSH supplemented with 30, 40 or 50% pLH was compared. Sixty-four Boer goat does were synchronized by progestagen-containing ear implant,...

Superovulation in cows with FSH preparation containing different amounts of LH (1995)

Smorag, Z, Beckers, Jean-François, Bychawski, S, Znanniecki, R

One of the main factors influencing the effectiveness of superovulation is the quality of gonadotropin used.Especially the proportion of FSH to Lh can play an important role.In the experiment...

A novel glycoprotein of the aspartic proteinase gene family expressed in bovine placental trophectoderm (1994)

Xie, Sancai, Low, Boon G., Nagel, Robert J., Beckers, Jean-François, Roberts, R. Michael

The pregnancy associated glycoproteins (PAG 1) that appear in the maternal serum of cattle and sheep soon after implantation are apparently inactive members of the aspartic proteinase family. Here we...

Plasmatic profiles of pregnancy-associated glycoprotein and progesterone levels during gestation in Churra and Merino sheep (1994)

Ranilla, MJ, Sulon, Joseph, Carro, MD, Mantécon, AR, Beckers, Jean-François

This study was carried out to determine ovine pregnancy-associated glycoprotein (oPAG) and progesterone (P4) levels in the serum of Churra and Merino ewes throughout gestation and the first month...

Molécules de la famille des protéases aspartiques dans le placenta des ruminants: hormones ou protéines ? (1994)

Beckers, Jean-François, Roberts, R. Michael, Zoli, André Pagnah, Ectors, Francis, Derivaux, Jules

The placenta of ruminant contains binucleate trophoblastic cells synthesizing proteins, migrating cross the barrier and fusing with endothelial cells of the endometrium. Recently described were two...

Preservation of oocyte and granulosa cell morphology in bovine preantral follicles cultured in vitro (1994)

Figueiredo, JR, Hulshof, SCJ, Nusgens, B, Bevers, MM, Ectors, Fabien, ...

Described in the present paper is a culture system that preserves oocyte and granulosa cell morphology in bovine preantral follicles during 5 d in vitro. The effects of additional hypoxanthine and...

Isolation and characterization of preantral follicles from fetal bovine ovaries (1994)

Hulshof, SCJ, Figueiredo, José Ricardo, Beckers, Jean-François, Bevers, MM

A simple, mechanical method is described for the isolation of preantral follicles bovine foetuses of 220-280 days of gestation. On average, 2918+621 (s.d.) preantral follicles were isolated per...

Immunocytochemical localization of vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY) in the bovine ovary (1994)

Hulshof, SCJ, Dijkstra, G, Van Der Beek, EM, Bevers, MM, Figueiredo, José Ricardo, Beckers, Jean-François, ...

The distribution of the neuropeptides vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY) was studied immunocytochemically in bovine ovaries from 3 mo of gestation up to and including...

Le point sur la production d’embryons in vitro: limitations et perspectives de la recherche (1994)

Thonon, Fabienne, Ectors, Fabien, Delval, Alain, Lenz, Harold, Touati, Kamal, Beckers, Jean-François, ...

Recent progress in gamete biology and early embryo development was responsible for great evolution of reproduction techniques in farm animals. Among these techniques, in vitro production of bovine...

Modification of immunoreactive EGF receptor after acute tubular necrosis induced by tobramycin or cisplatin (1994)

Leonard, I, Zanen, J, Nonclercq, D, Toubeau, G, Heuson-Stiennon, JA, Beckers, Jean-François, ...

Acute tubular necrosis induced by aminoglycoside antibiotics and various other nephrotoxins is followed by a regenerative process which leads to the restoration of damaged tubules. Several lines of...

Molécules de la famille des protéases aspartiques dans le placenta des ruminants: hormones ou protéines? (1994)

Beckers, Jean-François, Roberts, R. Michael, Zoli, André Pagnah, Ectors, Francis, Derivaux, J.

The ruminant placenta contains binucleate trophoblastic cells synthesizing proteins, migrating cross the barrier and fusing with endothelial cells of the endometrium. Recently described were two...

Preservation of Oocyte and Granulosa Cell Morphology in Bovine Preantral Follicles Cultured in Vitro (1994)

Figueiredo, J R, Hulshof, S C, Nusgens, Betty, Bevers, M M, Ectors, Fabien, ...

Described in the present paper is a culture system that preserves oocyte and granulosa cell morphology in bovine preantral follicles during 5 d in vitro. The effects of additional hypoxanthine and...

Development of a combined mechanical and enzymatic method for the isolation of intact preantral follicles from fetal, calf and adult bovine ovaries (1993)

Figueiredo, José Ricardo, Hulshof, SCJ, Ectors, Fabien, Fontes, RS, Nusgens, B, ...

The isolation of preantral follicles from the ovaries of bovine fetuses, calves and adult cows was performed using a simple, rapid mechanical and enzyme method. The ovaries were cut into small pieces...

Development of a Combined New Mechanical and Enzymatic Method for the Isolation of Intact Preantral Follicles from Fetal, Calf and Adult Bovine Ovaries (1993)

Figueiredo, J R, Hulshof, S C, Ectors, Fabien, Fontes, R S, Nusgens, Betty, ...

The isolation of preantral follicles from the ovaries of bovine fetuses, calves and adult cows was performed using a simple, rapid mechanical and enzyme method. The ovaries were cut into small pieces...

Le clonage par transfert de noyau dans l'espèce bovine: premiers résultats (1993)

Ectors, Francis, Ectors, Fabien, Delval, Alain, Thonon, Fabienne, Beckers, Jean-François

In 1987, Prather et al. have performed the first embryo cloning by nuclear transfer in the bovine species. Since, many researchers try to develop and to apply the technique. While the enucleation of...

Comparison between culture of bovine embryos in vitro versus development in rabbit oviducts and in vivo (1993)

Ectors, Fabien, Thonon, Fabienne, Delval, Alain, Fontes, Reginaldo S, Touati, Kamal, Beckers, Jean-François

The aim of this work was to evaluate the efficiency of different embryo culture methods for in vitro embryo production: development in co-culture with bovine oviductal epithelial cells (BOEC), in...

Le clonage par transfert de noyau dans l'espèce bovine: premiers résultats (1993)

Ectors, Francis, Ectors, Fabien, Delval, A, Thonon, Fabienne, Beckers, Jean-François

In 1987, Prather et al. have performed the first embryo cloning by nuclear transfer in the bovine species. Since, many researchers try to develop and to apply the technique. While the enucleation of...

Effect of estradiol supplementation on superovulation in swamp buffalo (1992)

Uoc, NT, Nguyen, BX, Ty, LV, Chupin, D, Beckers, Jean-François, Renard, JP

The effect of estradiol-17β (E2) supplementation on superovulation with (PMSG) or (FSH) was investigated in Swamp buffalo. Sixty-eight buffalo were treated in seven groups. Group 1 served as control...

Effects of repeated use of progestagen-PMSG treatment for estrus control in dairy goats out of breeding season (1992)

Baril, Gérard, Remy, Benoît, Vallet, JC, Beckers, Jean-François

Contents: In order to analyze the effects of repeated use of progestagen-PMSG treatment, estrus and pregnancy results have been analyzed for 1989 in a Saânen dairy goat herd in which breeding takes...

Light and Electron Microscopic Immunolocalization of Bovine Pregnancy-Associated Glycoprotein in the Bovine Placentome (1992)

Zoli, André Pagnah, Demez, Pierre, Beckers, Jean-François, Reznik, Michel, Beckers, Albert

A bovine pregnancy-associated glycoprotein (bPAG) of 67 kDa has previously been isolated from bovine fetal cotyledons. The objective of this study was to determine the cytological localization of...

Radioimmunoassay of a Bovine Pregnancy-Associated Glycoprotein in Serum: Its Application for Pregnancy Diagnosis (1992)

Zoli, André Pagnah, Guilbault, Louis A, Delahaut, Philippe, Ortiz, Wash Benitez, Beckers, Jean-François

A sensitive and specific double-antibody RIA for a bovine pregnancy-associated glycoprotein (bPAG) is described. The limit of detection was 0.2 ng/ml. The assay was specific for bPAG in that...

Observations sur l'utilisation de traitements gonadotropes répétés chez la chèvre laitière (1992)

Baril, Gérard, Remy, Benoît, Vallet, JC, Beckers, Jean-François

Observations on the repeated use of gonadotropin treatments in the dairy goat. Our studies have attempted to determine if the absence of oestrus observed in some goats after fluorogestone...

Immunocytochemical Evidence for Production of Luteinizing Hormone and Follicle-Stimulating Hormone in Separate Cells in the Bovine (1991)

Bastings, Eric, Beckers, Albert, Reznik, Michel, Beckers, Jean-François

In all mammalian females, follicular growth and maturation are essentially dependent on the pituitary gonadotropins, FSH and LH. These glycoprotein hormones have many similarities, but their action,...

Identification of the major pregnancy-specific antigens of cattle and sheep as inactive members of the aspartic proteinase family (1991)

Xie, Sancai, Low, Boon G., Nagel, Robert J., Kramer, Kyle K., Anthony, Russel V., Zoli, André Pagnah, ...

Pregnancy in cattle and sheep can be diagnosed by the presence of a conceptus-derived antigen in maternal serum that is secreted by trophoblast and placental tissue primarily as an acidic component...

Are Antibodies Responsible for a Decreased Superovulatory Response in Goats Which Have Been Treated Repeatedly with Porcine Follicle-Stimulating Hormone ? (1991)

Remy, Benoit, Baril, Gérard, Vallet, JC, Dufour, R, Chouvet, Claire, Saumande, Jean, ...

Repeated administration of xenogenic gonadotropins in human or animal species may be responsible for antibody production and refractoriness. An experiment was conducted in which goats were treated...

Purification and characterization of a bovine pregnancy-associated glycoprotein (1991)

Zoli, André Pagnah, Beckers, Jean-François, Wouters-Ballman, Patricia, Closset, Jean, Falmagne, Paul, Ectors, Francis

A 67000 Mr bovine pregnancy-associated glycoprotein (bPAG) has been isolated from fetal cotyledons and purified to homogeneity by HPLC. The purification was monitored by a double immunodiffusion test...

Immunocytochemical study of cell type distribution in the pituitary of Barbus barbus (Teleostei, Cyprindidae) (1991)

Toubeau, Gérard, Poilve, A, Baras, Etienne, Nonclercq, D, De Moor, S, Beckers, Jean-François, ...

Antisera to mammalian pituitary and placental hormones have been used to identify and localize the different cell types in the pituitary of the barbel (Barbus barbus, L.). The immunocytochemical...

Développement embryonnaire caprin in vitro: étude des conditions de culture (1991)

Fieni, Francis, Buggin, M, Tainturier, Daniel, Dumont, P, Perrin, J, Beckers, Jean-François, ...

Three culture Media: PBS; HAM F10 and B2 Menezo were used to compare and study the in vitro development of goats embryos. After 48h of culture in these media, the rate of Morulas developed was o%,...

Influence of breed of fetus on periparturient endocrine responses and subsequent milk production of Ayrshire dams (1990)

Guilbault, LA, Roy, GL, Beckers, Jean-François, Dufour, JJ

Purebred Ayrshire females were assigned to two groups based on the breed of fetus carried during gestation. In group 1, Limousin embryos were transferred nonsurgically into Ayrshire recipients (10...

L'insémination artificielle intra-utérine, transpéritonéale chez la chèvre: 2. Etude comparative du taux de fécondation après saillie ou insémination artificielle intra-utérine (1990)

Fieni, Francis, Buggin, M, Tainturier, Daniel, Beckers, Jean-François, Bach-Lijour, B, Bruyas, JF, ...

This study was carried out on 570 ovocytes. It shows that goats suprovulated due to FSH treatements of 16 mg Armour given over 3 days (in 8-4-4 mg/day) or 21 mg Armour over 4 days (in 7-6-4-4 mg/day)...

Multiplication des embryons chez les bovins: possibilités actuelles et futures (1989)

Ectors, Francis, Beckers, Jean-François, Ectors, Fabien, Delval, Alain, Touati, Kamal

Since several years, research efforts have been focused towards improving the reproductive potential of domestic animals. The authors present a review of different technics in particular the...

An immunological cryo-ultrastructural study of a sequential appearance of proteins in placental binucleate cells in early pregnancy in the cow (1989)

Morgan, G, Wooding, FBP, Beckers, Jean-François, Friesen, HG

Using the most sensitive immunocytochemical method available, on ultrathin frozen sections, the results in this paper demonstrate that bovine placental lactogen (bPL) is present in the earliest fetal...

Folliculogenèse et transplantation embryonnaire chez les ruminants (1989)

Beckers, Jean-François

In ruminant embryo transfer development, the limiting step remains the superovulation of the donor: using both PMSG and pituitary extracts, the superovulatory response is variable. In our research...

Mise au point sur la folliculogenèse (1989)

Touati, Kamal, Ectors, Fabien, Beckers, Jean-François, Ectors, Francis

Folliculogenesis is usually divided in two stages: the first one going from the primordial follicle to the secondary or preantral, the second leading the preantral follicle to the preovulatory or...

Effet d'une préstimulation ovarienne en début de cycle sur la réponse au traitement de superovulation chez la vache (1989)

Touati, Kamal, Bormans, M, Ectors, Fabien, Delval, A, Beckers, Jean-François, Ectors, Francis

In this study, we have induced superovulation in 67 heifers according to a known based treatment based on the administration of 32 mg (Armour Units) of FSH/LH (ratio LH/FSH=20%). The animals were...

Determination of porcine plasma follitropin levels during superovulation treatment in cows (1988)

Demoustier, M., Beckers, Jean-François, Closset, Jean, Gillard, J. L., Ectors, Francis

Porcine follicle stimulating hormone (pFSH) and porcine luteinizing hormone (pLH), are widely used to induce superovulation in cows. An advantage of this treatment is that the LH:FSH ratio can be...

Effect of duodenal ornithine infusion in cows on milk production and blood plasma constituents at two levels of feeding (1988)

Teller, E, Roets, E, Godeau, Jean-Marie, Reynaert, R, Beckers, Jean-François, Leroy, Pascal, ...

An ornithine solution, corresonding to 36.1 g ornithine/d, or an equivalent blank solution were each continuously infused into the duodenum of two lactating cows of the Friesian breed. The cows were...

Obtention de blastocystes après maturation et fécondation in vitro d'ovocytes de bovin: premiers résultats (1988)

Ectors, Fabien, Touati, Kamal, Beckers, Jean-François, Ectors, Francis

74.4% of two cells cow embryos are following in vitro maturation and fertilisation. Some embryos developed in rabbit's oviducts to morula and blastocyst stages. They wer frozen and thawed before...

Effect of trenbolone acetate associated with 17ß-oestradiol on reproductive performances of young growing fattening bulls (1988)

Istasse, Louis, Evrard, Pierre, Coignoul, Freddy, Gielen, M, Beckers, Jean-François, Maghuin-Rogister, Guy, ...

Bulls were implanted with an ear pellet of trenbolone acetate and oestradiol in association. Some treated bulls produced a sperm without spermatozoa but there were no significant differences in...

Trinucleate cells and the ultrastructural localisation of bovine placental lactogen (1987)

Wooding, FBP, Beckers, Jean-François

Bovine placental lactogen activity is shown by immunogold electron microscopy to be restricted to (a) the granules and the Golgi body from which they form in the bovine fetal trophectodermal...

Immunodetection of bovine chorionic somato-mammotrophin (bCS) (1985)

Verstegen, J, Fellmann, D, Beckers, Jean-François

Bovine chorionic somatomammotrophin (bCS) was detected in the bovine placenta by using an immunoenzymatic procedure. This hormone appears mainly located in teh binucleate cells of the foetal...

Dosage radioimmunologique de l'alpha-MSH: Elaboration d'un antisérum hautement spécifique: application chez le rat (1985)

Verstegen, John, Ghaenen, G, Dessy, Cécile, Beckers, Jean-François

A highly specific and sensitive RIA for alpha-MSH has been developed. Its main characteristic is the possibility to mesure the alpha-MSH in the whole plasma without extraction. The double incubation...

Localisation immunocytochimique de l'alphamelanotropine dans le placenta bovin (1985)

Verstegen, John, Fellmann, Dominique, Beckers, Jean-François

The immunocytochemical study of the bovine placenta has demonstrated the presence of cells containing alphamelanotropic hormones, in the decidual epithelium, since the 4th month of pregnancy. The...

L'anoestrus du post-Partum (1984)

Derivaux, Jules, Beckers, Jean-François, Ectors, Francis

The authors give a survey of the actual knowledge about the fundamental endocrinology of the ovarian cycle in the bovine. In an experiment using 5 dry cows, 20 cows milked twice daily, and 5 freely...

A homologous radioimmunoassay for canine prolactin: plasma levels during the reproductive cycle (1983)

De Coster, R, Beckers, Jean-François, Beerens, D, De Mey, J

A method is described for the purification of canine prolactin, involving preparative isoelectrofocusing. Canine prolactin has a molecular weight of 23 000 daltons, an isoelectric point of 5.7 and...

Dosage radioimmunologique de l'hormone placentaire somatotrope et mammotrope bovine (1982)

Beckers, Jean-François, De Coster, R, Wouters-Ballman, Patricia, Fromont-Liénard, Ch, Ectors, Francis

Highly specific antisera were obtained from rabbits immunized with a purified preparation of Bovine Placental Somatomammotropin leading to the development of a sensitive radioimmunoassay. Teh values...

Dosage de l'hormone placentaire somatotrope et mammotrope bovine par liaison radio-compétitive aux récepteurs membranaires (1981)

Beckers, Jean-François, Ectors, Francis

Bovine placental somatomammotropin was labelled with I125 using the lactoperoxidase method. This allowed the development of radioreceptor assays using hepatic and mammary tissues of pregnant rabbits....

Plasma insulin level in double-muscled and conventional bulls during the first year of life (1981)

Michaux, C, Beckers, Jean-François, De Fonseca, M, Hanset, R

Concentration of plasma insulin has been determined by radioimmunoassay in conventional and double-muscled bulls at 80 (I1), 131 (I2), 227 (I3) and 370 I(4) d of age. Double-musceld have lower plasma...

Isolement d'une hormone placentaire bovine présentant une activité analogue à la prolactine et à l'hormone de croissance (1980)

Beckers, Jean-François, Fromont-Liénard, Ch, Wouters-Ballman, Patricia, Ectors, Francis

Isolation from bovine cotyledon extracts of an hormone with somatotrophic and mammotrophic activity was performed using this hormone during the successive steps of purification, its prolactinic and...

Variations de la LH, de la FSH, du 17 ß oestradiol et de la progestérone au cours du cycle oestral de la chienne (1979)

De Coster, R, Beckers, Jean-François, Wouters-Ballman, Patricia, Ectors, Francis

Plasma levels of progesterone, 17-beta-oestradiol, LH and FSH were measured by radioimmunoassay in five beagle bitches during two consecutive estrous cycles. Progesterone level rises at the end of...

Variations nycthémérales de la testostérone et de la lutropine plasmatiques chez le chien (1979)

De Coster, R, Beckers, Jean-François, Wouters-Ballman, Patricia, Ectors, Francis

Diurnal variations of plasmatic testosterone and lutropin were determined by radioimmunoassay in seven male beagle dogs. Blood samples were withdrawn hourly during 24 hours or every 20 min during 8...

Effet de l'azide de sodium sur la dégradation de la progestérone dans les échantillons de sang total chez les bovins (1979)

Delahaut, Philippe, Beckers, Jean-François, Ectors, Francis

Progestérone degradation was measured in bovine blood samples left on the bench in air at room temperature for a few days. Progesterone level is reduced by 50% after 4 to 6 h and this degradation...

Dosages radioimmunologiques (1978)

Beckers, Jean-François, Ectors, Francis

Séminaire de Perfectionnement pour les ingénieurs agronomes issus des facultés de Gembloux et de Louvain

Induction de l'oestrus chez les génisses en anoestrus fonctionnel (1978)

Beckers, Jean-François, Wouters-Ballman, Patricia, Ectors, Francis, Derivaux, Jules

Fuctional anoestrus is frequently encountered during winter months and most specially in beef cattle. Ovaries and genital tract display a resting, dormant conditions. Progesterone, 17-beta-oestradiol...

Evolution du taux de cortisol plasmatique chez le veau de la naissance à l'âge de 14 jours (1977)

Massip, Alban, Wouters-Ballman, Patricia, Beckers, Jean-François, Ectors, Francis

Plasma cortisol was recorded in 15 calves from birth to 14 days of age by a radioimmunoassay technique. At birth mean cortisol value is 67.3 ng/ml; 6 hours later it decreases by 58.4% then it...

Bovine follitropin: Isolation and characterization of the native hormone and its alpha and ß subunits (1977)

Beckers, Jean-François, Closset, Jean, Maghuin-Rogister, Guy, Hennen, Georges

1. A reproducible procedure was developed for the purification of bovine follitropin. 2. The methode involved ammonium sulfate precipitation, ion exchange and adsorption chromatography,...

Prostaglandines et cycle sexuel chez les animaux domestiques (1976)

Derivaux, Jules, Ectors, Francis, Beckers, Jean-François

In some domestic animal species, cow, ewe, sow, mare, luteal regression and therefore oestral regulation, depends on the action of a luteolytic of uterine origin. This luteolysine should be but a...

Hormonelle Befunde bei Störungen der Ovarialfunktion des Rindes (1976)

Derivaux, Jules, Ectors, Francis, Beckers, Jean-François

The hormonal pattern was studied in 54 animals: 34 heifers with seasonal anoestrus, 13 cows with post-partum anoestrus, 5 cows with nymphomania and 2 cows superovulated. Seasonal and post partum...

Variation du 17 ß oestradiol au cours du cycle oestral chez la vache (1975)

Ectors, Francis, Beckers, Jean-François, Ballman, Patricia, Derivaux, Jules

Le dosage du 17 beta oestradiol plasmatique, sans recours préalable à la chromatographie de partage, a pu être réalisé et ce en raison de la haute spécificité de l'antisérum utilisé. Le 17...

Le dosage radioimmunologique de la progestérone plasmatique chez la vache (1975)

Beckers, Jean-François, Ballman, Patricia, Ectors, Francis, Derivaux, Jules

Le dosage de la progestérone chez la vache a été réalisé par la méthode radioimmunologique sans purification préalable. Le taux de progestérone varie de 0,60 ng/ml le jour de l'oestrus à 6,4...