References of "Ponthier, Jérôme"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailSquamous metaplasia of the prostate and diffuse alopecia in a 13-year-old castrated dog due to chronic ingestion of exogenous estradiol
Van Den Berghe, Femke ULiege; Ponthier, Jérôme ULiege; Deleuze, Stefan ULiege

in Reproduction in Domestic Animals (2012, August), 47(S4), 561

Introduction. A 13-year old whippet with a generalized progressive alopecia since 2 years was referred to our clinic to perform a low-dose dexamethasone stimulation test and abdominal ultrasound to ... [more ▼]

Introduction. A 13-year old whippet with a generalized progressive alopecia since 2 years was referred to our clinic to perform a low-dose dexamethasone stimulation test and abdominal ultrasound to exclude or confirm Cushing disease. The dog had previously been treated with trilostane for 4 months without having any positive effects. Earlier blood analysis showed no significantly abnormalities and ACTH stimulation test was negative. Having bilateral cryptorchidism, the dog was castrated at young age. Clinical findings and treatment. Abdominal ultrasound revealed a slightly enlarged right adrenal gland (diameter of 1 cm at the cranial part). The prostate was enlarged and heterogeneous with multiple anechogenic cavities, indicating hormonal stimulation. Craniad the prostate and ventrally of the bladder, a hypoechogenic, oval structure (3 cm by 1.7 cm) could be seen, and was suspected to be a remaining cryptorchide testicle. Fine needle aspiration however showed that the structure contained a thick purulent liquid, with large amounts of polymorhonuclear white blood cells. Blood analysis revealed a leukocytosis (29370/mm3) with neutrophilia (23202/mm3). Low-dose dexamethasone test definitely excluded Cushing disease (basal cortisol levels 2,17 µg/dl; cortisol at 4 and 8 hours < 1 µg/dl). A prostatic wash was performed and revealed a severe prostatitis and presence of keratinized prostatic cells, indicating a squamous metaplasia of the prostate. Measurement of seric LH levels (LH Witness®, Synbiotics) showed an LH concentration lower than 1 ng/ml, indicating a hormonal negative feedback on the hypothalamo-hypophyso-gonadal axis. After a more thorough anamnesis, it became clear that the dog was licking and ingesting a transdermal estradiol containing cream (Estrogel®) from his owner, since two years, causing his symptoms. The dog was put on antibiotic treatment for the prostatitis (enrofloxacine 10 mg/kg SID) and underwent surgery to excise the abscess cranial of the prostate. The two ductuli deferentes were attached to this structure. Histopathological analysis revealed this tissue to be embryological remanents or a morphological anomaly with a urogenital origin. Control after 4 weeks showed that the prostate slightly decreased in volume, however, anechogenic cavities where still present of which one increased in volume. The alopecia was still present as well, both probably due to a prolonged action of the estrogens. Conclusion. Even though injectable estrogen preparations are not longer available in veterinary medicine in Europe, a thorough anamnesis towards other exogenous estrogen sources is still necessary and can reduce the number of supplementary exams performed. [less ▲]

Detailed reference viewed: 104 (14 ULiège)
Full Text
Peer Reviewed
See detailA flow cytometric study on the effect of myeloperoxidase on stallion spermatozoal motility and structure
Ponthier, Jérôme ULiege; Parrilla Hernandez, Sonia ULiege; Van Den Berghe, Femke ULiege et al

in Journal of Equine Veterinary Science (2012, August), 32(8), 509

Myeloperoxidase (MPO) is a pro-oxidant enzyme that is normally contained in neutrophils. MPO has recently been associated with keratinized cells and with decreased post-thaw motility in stallion semen [1 ... [more ▼]

Myeloperoxidase (MPO) is a pro-oxidant enzyme that is normally contained in neutrophils. MPO has recently been associated with keratinized cells and with decreased post-thaw motility in stallion semen [1]. The aim of the study was to determine effects of experimental addition of active MPO on motility, mitochondrial potential, apoptosis induction, membrane and acrosome integrity in equine semen. Three stallions were used and semen was collected four times. Extended (INRA96TM) semen was processed for density gradient centrifugation (Equipure Bottom Layer®) [2]. Purified pellet was re-extended to 100x106spermatozoa/ml in INRA96TM and divided in 3 samples. One sample was used for control and active human MPO (Calbiochem, Merck) was added in the other two samples to final concentration of 5 or 50 ng/ml. After incubation (2 hours, 20°C), motility was analysed with Computer Assisted Semen Analysis (IVOS, Hamilton-Throne, Beverly, MA, USA) and cytometric analyzes were perfomed with EasyCyte (IMV). Mitochondrial potential and apoptosis were assayed using Guava Mitopotential JC-1 and 7-AAD kit (Millipore). Membrane and acrosome integrity were respectively assayed with PI (Propidium Iodide) (Invitrogen) and PNA (Peanut Agglutinin-Fluorescein Iso Thio Cyanate) (Sigma-Aldrich). Statistical differences (p<0.05) were determined using Kruskall-Wallis test. No effect of the stallions was observed on parameters assayed in this study. Unlike total motility, progressive motility was decreased in both MPO concentrations (p<0.001). MPO addition had no effect on membrane and acrosome integrity. No differences were detected for the percentages of spermatozoa having polarised or depolarised mitochondria. Apoptosis, assayed by 7-AAD fluorescence, was not increased by the treatments. Our results agree with previously published effects of in vitro ROS production systems with xanthine oxidase [3], showing an effect on motility but no influence on mitochondria and membrane or acrosome integrity. However, membrane lipoperoxidation was increased by ROS in this study [3], and it could be linked to the impaired motility also observed in our protocol. Further studies with increasing concentrations of added MPO should be conducted to correlate motility with lipoperoxidation. References [1] Ponthier J, Desvals M, Franck T, de la Rebiere de Pouyade G, Spalart M, Palmer E, Serteyn D, Deleuze S. Myeloperoxidase in equine semen: Concentration and Localization during freezing processing. Journal of Equine Veterinary Science 2012;32: 32-37. [2] Edmond AJ, Teague SR, Brinsko SP, Comerford KL, Waite JA, Mancill SS, Love CC, Varner DD. Effect of density-gradient centrifugation on quality and recovery rate of equine spermatozoa. Animal Reproduction Science 2008;107: 318-318. [3] Baumber J, Ball BA, Gravance CG, Medina V, Davies-Morel MC. The effect of reactive oxygen species on equine sperm motility, viability, acrosomal integrity, mitochondrial membrane potential, and membrane lipid peroxidation. J Androl 2000;21: 895-902. [less ▲]

Detailed reference viewed: 66 (10 ULiège)
Full Text
Peer Reviewed
See detailMyeloperoxidase as an indicator of endometritis in the mare: preliminary results
Parrilla Hernandez, Sonia ULiege; Franck, Thierry ULiege; Ponthier, Jérôme ULiege et al

in Reproduction in Domestic Animals (2012, August), 47(suppl 5), 65

Diagnosis of endometritis in the mare is routinely based on the presence of polymorphonuclear cells (PMNs) on endometrial smears. Studies show a relation between PMNs and myeloperoxidase (MPO), an enzyme ... [more ▼]

Diagnosis of endometritis in the mare is routinely based on the presence of polymorphonuclear cells (PMNs) on endometrial smears. Studies show a relation between PMNs and myeloperoxidase (MPO), an enzyme released by PMNs during degranulation or after cell lysis, in many fluids and tissues. The aims of this study were to assess the presence and concentration of MPO in the mare’s uterus, and to investigate its relation with PMNs. Thirty-six cycles from 28 mares (ages ranging from 6 to 22 years) were used. Endometrial cytological samples were obtained with a small volume uterine flush and either a uterine cotton swab or a cytobrush, when a follicle >35 mm was observed by ultrasound. The smears were stained with Diff-QuickÒ and one or more PMNs per field (400·) was diagnosed as endometritis. The supernatant of the flushes was used to measure MPO concentration with a specific equine MPO ELISA assay. Our results showed the presence of MPO in the equine uterus during oestrus (mean = 2839 + 2785). MPO concentrations were signifi- cantly (p < 0.05) higher in samples with positive cytological results. Occasionally, some samples with negative cytological results showed high MPO concentration, but the opposite was never observed. Clinical signs of endometritis are not always present, or they may be delayed. An early diagnostic improves the success of treatment. Our results show that high quantities of MPO in endometrial samples indicate the presence of PMNs. Further studies are needed to determine if MPO concentration could be routinely used as a tool of early detection of endometritis. [less ▲]

Detailed reference viewed: 154 (16 ULiège)
Full Text
Peer Reviewed
See detailEffect of artificial insemination site on post-mating endometritis in mares
Rodier, Clémentine; Ponthier, Jérôme ULiege; Parrilla Hernandez, Sonia ULiege et al

in Reproduction in Domestic Animals (2012, August), 47(suppl 5), 103

Aim of the study was to determine the effect of artificial insemination (AI) location on post-mating endometrial inflammation 1 and 6 days after AI. Six mares with ages ranging from 12 to 23 years were ... [more ▼]

Aim of the study was to determine the effect of artificial insemination (AI) location on post-mating endometrial inflammation 1 and 6 days after AI. Six mares with ages ranging from 12 to 23 years were inseminated with a same batch of frozen semen for 3 consecutive cycles. Mares were inseminated with the following procedures in a random order: (1) Deep uterine insemination with 4ml of semen; (2) Horn bifurcation with 4ml of semen; (3) Horn bifurcation with 4ml of semen and 6ml of extender. During each cycle, Cotton (C) and Brush (B) swabs were collected at 4 different moments: mid- dioestrus, mares with a 35mm follicle, 24h and 6 days after AI. Swabs were smeared on slides, fixed and stained (Diff-Quick®) before examination under light microscopy. Proportions of inflammatory and epithelial cells were determined and differences were studied with kruskal-wallis test for non-parametric data. Distensions of uterine lumen due to intraluminal fluid observed during ultrasound exams were measured and recorded. Quality of slides was better (p=0.0006) with B swabs than C swabs with 97% versus 65% of slides readable. B swabs were associated with higher percent of endometrial cells retrieved (p=0.0323), making them a better tool for endometritis diagnosis, which is consistent with our previous reports. Volume of intraluminal fluid and percent of inflammatory cells, both on B and C swabs, were not influenced by AI location regardless the timing of sampling. Small volume deep uterine AI did not significantly affect inflammatory response by the endometrium in our experiment. [less ▲]

Detailed reference viewed: 122 (8 ULiège)
Full Text
Peer Reviewed
See detailRaw semen concentration directly influences CASA velocity pathways
Parrilla Hernandez, Sonia ULiege; Deleuze, Stefan ULiege; Van Den Berghe, Femke ULiege et al

in Journal of Equine Veterinary Science (2012, August), 32(8), 505

We observed an influence of the stallion on volume, spermatozoa concentration and all CASA parameters (p<0.0001), which are highly dependant on each other due to geometrical association of these data ... [more ▼]

We observed an influence of the stallion on volume, spermatozoa concentration and all CASA parameters (p<0.0001), which are highly dependant on each other due to geometrical association of these data. That stallion effect may have interfered with the associations we observed as stallions seem to have specific concentration and motility pathways. More studies, with more replicates, will allow comparing results from a same stallion and further establish the correlations we report here. [less ▲]

Detailed reference viewed: 139 (19 ULiège)
Full Text
See detailOrigine et effet de la myéloperoxydase lors de la congélation du sperme d'étalon
Ponthier, Jérôme ULiege

Doctoral thesis (2012)

Semen freezing allows worldwide commercialization of equine genetic. Despite improvement of techniques, semen of 20% of stallions remains unfreezable. Currently, post-thaw semen quality is only determined ... [more ▼]

Semen freezing allows worldwide commercialization of equine genetic. Despite improvement of techniques, semen of 20% of stallions remains unfreezable. Currently, post-thaw semen quality is only determined by progressive motility, but its definition is not standardised. Spermatozoa are highly differentiated cells and freezing lesions can occur on DNA, membrane, mitochondria or acrosome. Current research focuses on prediction of freezability, improvement of freezing extenders and prevention of Reactive Oxygen Species (ROS) effects. Under its O2 form, oxygen is inactive and oxidase or oxygenase enzymes are required to produce ROS. Two pathways of ROS production in semen are described: the intrinsic pathway reflecting ROS escaping from the spermatozoon mitochondria and the extrinsic pathway corresponding to ROS produced by inflammatory cells. ROS induce DNA fragmentation, lipid peroxidation, apoptosis and decreased motility of spermatozoa. Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutrophils during degranulation or after lysis. It is responsible for formation of hypochlorous acid, a strong oxidant, which could damage spermatozoa. However, MPO presence and effects have never been investigated in equine semen. The first aim was to assay presence of MPO in equine thawed semen and to determine a relation between MPO concentration and post-thaw semen parameters. 35 straws from different stallions were analyzed. Post-thaw spermatozoa and MPO concentrations, viability, morphology, progressive and total motility were determined. Our study showed that thawed semen contains large amounts of free MPO. High MPO concentration samples showed lower total and progressive motility. Higher proportion of acrosome reaction was observed in late examinations of the high MPO concentration group. As MPO was present in frozen semen and did interfere with its quality, timing and origin of its release was determined during the freezing process. Forty ejaculates were frozen with a classical procedure. MPO ELISA and MPO immunocytochemistries (ICC) were assayed in raw semen, centrifugation supernatant, and after cooling down to 4°C. Post-thaw MPO concentration and spermogram parameters were determined. MPO concentration increased after cooling and thawing when compared to fresh semen. As temperature decreased, MPO was higher in post-thaw poor quality samples. Non-sperm cells (NSC) showed various degrees of MPO-ICC, and were mostly epithelial cells with nuclear picnosis. Elastase, another neutrophil pro-inflammatory enzyme, was also assayed in post-thaw semen. In twenty ejaculates, NSC concentration was determined in fresh semen. Post-thaw motilities were determined by CASA; MPO and elastase concentrations were assayed by ELISA. Post-thaw elastase concentrations were low and there was no difference according to semen quality. NSC or MPO concentrations were not correlated to elastase concentration. NSC concentration was higher in unfreezable semen and correlated to post-thaw MPO concentration. To confirm MPO release by NSC during freezing, the effect of washing semen with density gradient centrifugation (DGC) was then assayed on NSC and MPO concentrations. NSC and MPO concentrations were assessed at each step and MPO localization was performed by ICC. DGC washing decreased NSC and MPO concentrations in post-thaw semen and NSC were mainly remaining in DGC supernatant. MPO concentration was correlated with NSC concentration in the upper layer of the DGC supernatant and in post-thaw semen. NSC were epithelial cells showing MPO-ICC staining. Fresh semen MPO concentration had no effect on fresh or post-thaw semen quality, while post-thaw semen concentrations were correlated with decreased motility. To understand these findings, concentration, activity and structure of MPO present in seminal plasma, sperm-rich pellet and post-thaw semen were assayed. Factor inducing MPO release was determined by adding or not glycerol in samples stored at 4°C or 20°C. Total MPO was high in seminal plasma and thawed semen and low in sperm-rich pellet. Active MPO was high in sperm-rich pellet and low in seminal plasma and post-thaw semen. MPO concentrations were correlated in post-thaw and in semen cooled at 4°C with or without glycerol. Active MPO in sperm-rich pellet and post-thaw progressive motility were highly negatively correlated. MPO present in fresh semen is mainly the native inactive enzyme subunit. To confirm our previous findings, effect of active MPO and fresh or frozen-thawed NSC was assayed on purified spermatozoa motility, mitochondrial potential, membrane and acrosome integrity. Highest MPO concentration tested (50ng/ml) decreased motility. However, highest MPO concentration did not affect mitochondrial potential, membrane or acrosome integrity. Thawed NSC did decrease motility and mitochondrial potential when compared to fresh NSC, suggesting a synergic effect between MPO and other products released by NSC after thawing. Temperature decrease during freezing process increases MPO concentration and post-thaw concentration is negatively associated to post-thaw motilities. ICC slides have shown MPO presence on epithelial keratinized and pycnotic cells while neutrophils were rarely observed. Semen washing with DGC decreases MPO and NSC concentrations in post-thaw semen as NSC and MPO concentrations were positively correlated. MPO present in seminal plasma is native and inactive form while MPO present in sperm-rich pellet is active and negatively correlated to the post-thaw progressive motility. Addition of active MPO in semen decreased motility but had no effect on acrosome integrity, despite what had previously been suggested. Thawed NSC addition to spermatozoa decreased mitochondrial potential, suggesting a synergic effect between MPO and other factors released by NSC. Further studies should investigate the origin of high inactive MPO concentrations in fresh semen. Other studies should be conduced about the origin of epithelial keratinized pyknotic NSC in fresh semen and the pathophysiological mechanism leading to their MPO release during freezing. Large scale studies should be conducted to confirm the use of NSC concentration in fresh semen or active MPO concentration in sperm rich pellet as freezability prognosis. Further studies should also investigate effect of MPO specific inhibitors. [less ▲]

Detailed reference viewed: 240 (44 ULiège)
Full Text
Peer Reviewed
See detailMyeloperoxidase in Equine Semen: Concentration and Localization during Freezing Processing
Ponthier, Jérôme ULiege; Desvals, Maud; Franck, Thierry ULiege et al

in Journal of Equine Veterinary Science (2012), (32), 32-37

Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutro- phils during degranulation or after lysis. Post-thaw semen contains MPO, and concen- tration of this enzyme is associated ... [more ▼]

Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutro- phils during degranulation or after lysis. Post-thaw semen contains MPO, and concen- tration of this enzyme is associated with decreased motility. The aim of this study was to determine kinetics of MPO concentration during freezing, its origin, and its impact on frozenethawed semen. Forty ejaculates were used. Semen was frozen using the classical freezing procedure. MPO concentrations were assayed in fresh semen, after centrifuga- tion, and after cooling down to 4 C. Post-thaw MPO assay results and spermogram characteristics were determined. MPO immunocytochemistry was performed on 4 different ejaculates at each step of freezing procedure. MPO concentration increased after cooling down to 4 C and thawing compared with fresh semen. As temperature decreased, MPO was higher or tended to be higher in post-thaw poor quality samples. Nonsperm cells showed various degrees of MPO immunostaining and were observed as epithelial cells with nuclear pyknosis and keratinization. MPO immunostaining increased in medium and decreased in nonsperm cells during freezing. Our study shows that MPO concentration in equine semen increases when temperature decreases. We hypothesize that nonsperm cells present in fresh semen could release MPO. [less ▲]

Detailed reference viewed: 73 (17 ULiège)
Full Text
Peer Reviewed
See detailSperm quality analysis in XX, XY and YY males of the Nile tilapia (Oreochromis niloticus).
Gennotte, Vincent ULiege; François, Ekniel; Rougeot, Carole ULiege et al

in Theriogenology (2012)

In Nile tilapia (Oreochromis niloticus), individuals with atypical sexual genotype are commonly used in farming (use of YY males to produce all-male offsprings), but they also constitute major tools to ... [more ▼]

In Nile tilapia (Oreochromis niloticus), individuals with atypical sexual genotype are commonly used in farming (use of YY males to produce all-male offsprings), but they also constitute major tools to study sex determinism mechanisms. In other species, sexual genotype and sex reversal procedures affect different aspects of biology such as growth, behaviour and reproductive success. The aim of this study was to assess the influence of sexual genotype on sperm quality in Nile tilapia. Milt characteristics were compared in XX (sex-reversed), XY and YY males in terms of gonadosomatic index, sperm count, sperm motility and duration of sperm motility. Sperm motility was measured by computer-assisted sperm analysis (CASA) quantifying several parameters: total motility, progressive motility, curvilinear velocity, straight line velocity, average path velocity and linearity. None of the sperm trait measured differed significantly between the three genotypes. Mean values of gonadosomatic index, sperm concentration and sperm motility duration of XX, XY and YY males respectively ranged from 0.92 to 1.33 %, from 1.69 to 2.22 × 10(9) cells mL-1 and from 18’04’’ to 27’32’’. Mean values of total motility and curvilinear velocity 1 min after sperm activation respectively ranged from 53 to 58 % and from 71 to 76 µm s-1 for the three genotypes. After 3 min of activity, all the sperm motility and velocity parameters dropped by half and continued to slowly decrease thereafter. Seven min after activation, only 9 to 13 % of spermatozoa were still progressive. Our results prove that neither sexual genotype nor hormonal sex reversal treatments affect sperm quality in male Nile tilapias with atypical sexual genotype. [less ▲]

Detailed reference viewed: 111 (15 ULiège)
Full Text
Peer Reviewed
See detailDystocies équines: Données descriptives et approche de la gestion des soins intensifs
Deleuze, Stefan ULiege; de la Rebière de Pouyade, Geoffroy ULiege; Sandersen, Charlotte ULiege et al

Conference (2011, December 02)

La fréquence de fourbures rencontrées après une dystocie semble faible par rapport à la littérature. L’ajout d’héparines fractionnées aux traitements habituels de la métrite du post-partum (ocytocine ... [more ▼]

La fréquence de fourbures rencontrées après une dystocie semble faible par rapport à la littérature. L’ajout d’héparines fractionnées aux traitements habituels de la métrite du post-partum (ocytocine, lavage utérins, antibiotiques et anti-inflammatoires) semble intéressant pour réduire le risque de fourbure. [less ▲]

Detailed reference viewed: 129 (27 ULiège)
See detailGestion du poulinage
Ponthier, Jérôme ULiege; Deleuze, Stefan ULiege

Conference given outside the academic context (2011)

Detailed reference viewed: 55 (18 ULiège)
Full Text
See detailEQUINE SEMEN FREEZING: STATE OF THE ART AND PERSPECTIVES.
Ponthier, Jérôme ULiege

Conference (2011, November 19)

Depuis vingt ans, la congélation du sperme a permis de diffuser la génétique des étalons. Les congélations effectuées en dehors des saisons sportives permettent d’inséminer de nombreuses juments pendant ... [more ▼]

Depuis vingt ans, la congélation du sperme a permis de diffuser la génétique des étalons. Les congélations effectuées en dehors des saisons sportives permettent d’inséminer de nombreuses juments pendant que les étalons concourent dans des lieux éloignés. Les éleveurs ont en permanence accès à des doses d’insémination sans risques sanitaires. Cependant, malgré une bonne qualité de sperme frais, 20% des éjaculats équins ne supportent pas la congélation (Vidament, 2005). Le but de cette présentation est de revoir la physiologie du spermatozoïde et d’en discuter les implications dans le contexte de la congélation. Les améliorations des techniques de congélation présentes ou à venir seront aussi évoquées. [less ▲]

Detailed reference viewed: 74 (13 ULiège)
Full Text
See detailMrozenie nasienia u koni - stan obecny i perspektywy
Ponthier, Jérôme ULiege

in Gajewski, Zdsislaw; Malinowski, Edward; Wehrend, Axel (Eds.) Rozrod Koni: aktualne poglady (2011, November 19)

Aim of this paper is to review equine semen freezing procedures. Spermatozoa formation inside the testis, spermatozoa anatomy and physiology will be summarized, highlighting structures and/or functions ... [more ▼]

Aim of this paper is to review equine semen freezing procedures. Spermatozoa formation inside the testis, spermatozoa anatomy and physiology will be summarized, highlighting structures and/or functions injured during freezing/thawing process. Current quality standards will be defined for fresh and thawed semen with a special attention on total and progressive motilities and different definitions of these parameters in literature. New ways of semen analysis (as flow cytometry) will be discussed for their scientific and clinical implications. Freezing procedures will and new freezing procedures will be discussed. Future developments and progress in freezing methods will be exposed, as prediction of post-thaw semen quality on fresh semen basis, improvement of freezing extenders and prevention of reactive oxygen species effects. [less ▲]

Detailed reference viewed: 78 (7 ULiège)
Full Text
Peer Reviewed
See detailEffect of Deferoxamine Mesylate on Freezability of Blood Supplemented Canine Semen
Van Den Berghe, Femke ULiege; Rijsselaere, Tom; Van Soom, Ann et al

Poster (2011, September)

Detailed reference viewed: 69 (20 ULiège)
Full Text
Peer Reviewed
See detailSuperovulation in the mare with commercially available pFSH
Parilla Hernandez, Sonia; Deleuze, Stefan ULiege; Beckers, Jean-François ULiege et al

in Reproduction in Domestic Animals (2011), 46(s3), 138

Further studies on Stimufol with larger numbers, should be conducted as it might prove inexpensive and easy to superovulate mares.

Detailed reference viewed: 154 (32 ULiège)
Full Text
See detailGestion de la jument poulinière et de l'étalon
Ponthier, Jérôme ULiege; Deleuze, Stefan ULiege

Conference given outside the academic context (2011)

Detailed reference viewed: 67 (12 ULiège)
Full Text
See detailLa spermatogenèse, la libido et la dose
Ponthier, Jérôme ULiege; Lecrenier, Marie-Caroline; Parrilla Hernandez, Sonia ULiege et al

Conference given outside the academic context (2010)

Detailed reference viewed: 73 (5 ULiège)
Full Text
Peer Reviewed
See detailAssociation between Myeloperoxidase concentration in equine frozen semen and post thawing parameters
Ponthier, Jérôme ULiege; Franck, Thierry ULiege; Detilleux, Johann ULiege et al

in Reproduction in Domestic Animals (2010), 45(5), 811-816

Despite improvement of techniques, semen of 20% of stallions remains unfreezable. Recent studies focused on impact of reactive oxygen species and oxidant enzymes on semen characteristics. Myeloperoxidase ... [more ▼]

Despite improvement of techniques, semen of 20% of stallions remains unfreezable. Recent studies focused on impact of reactive oxygen species and oxidant enzymes on semen characteristics. Myeloperoxidase (MPO) is a pro-oxidant enzyme contained in and released by neutrophils during degranulation or after cell lysis. It is responsible for the formation of hypochlorous acid, a strong oxidant agent which could damage spermatozoa. The aim of this study was to determine the relation between MPO concentration and characteristics of frozen semen from stallions. Thirty five straws from different stallions were analyzed. Post-thawing spermatozoal concentration, progressive and total motility were determined by CASA. Freezability was determined according to post-thawing progressive motility (over or under 15%). Percent of alive spermatozoa and abnormal forms were determined after Eosin-Nigrosin and Diff-Quick® staining respectively. Post-thawing MPO concentration was measured by ELISA. Our study shows that frozen thawed semen contains large amounts of free MPO. We also observed that post-thawing MPO ELISA assay can be used as an indicator of equine semen freezability. High MPO concentration samples showed lower total and progressive motility. A higher proportion of abnormal head shape associated with acrosome reaction was observed in our late examinations of the high concentration MPO group. Our results show that MPO adversely affects total and progressive motility of equine semen. A negative correlation between normal motile forms and MPO concentration was also observed. The effect of MPO on dead or abnormal forms remains to be precised. [less ▲]

Detailed reference viewed: 146 (54 ULiège)
Full Text
Peer Reviewed
See detailCytological diagnosis of endometritis in the mare: a comparative study
Daspet, Sarah-Morgane; Ponthier, Jérôme ULiege; Jolly, Sandra ULiege et al

in Reproduction in Domestic Animals (2010, September), 45s3

It was concluded that the brush swab was a promising diagnostic tool for use in field conditions.

Detailed reference viewed: 144 (16 ULiège)
Full Text
Peer Reviewed
See detailIs neutrophil elastase associated with myeloperoxidase concentration and post-thawing parameters in equine frozen semen?
Ponthier, Jérôme ULiege; de la Rebière de Pouyade, Geoffroy ULiege; Desvals, Maud et al

in Animal Reproduction Science (2010), 121S

Non sperm cells concentration is higher in unfreezable semen. A relation between non-sperm cells in fresh semen and MPO and post thawing quality has been observed. Neutrophil Elastase seems to have no ... [more ▼]

Non sperm cells concentration is higher in unfreezable semen. A relation between non-sperm cells in fresh semen and MPO and post thawing quality has been observed. Neutrophil Elastase seems to have no effect on semen characteristics and to be not associated with on-sperm cells and freezability. [less ▲]

Detailed reference viewed: 99 (34 ULiège)
Peer Reviewed
See detailMicroscopic study of equine oocyte maturation within quaternary follicles.
Ponthier, Jérôme ULiege; Beckers, Jean-François ULiege; Deleuze, Stefan ULiege

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: 99 (34 ULiège)