Stefan Deleuze

Prof. Dr. Stefan Deleuze

Small animal and Equine Reproduction, Department of Clinical science, Veterinary Faculty, University of Liege, Belgium
orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 May 2021 in Animals
Verified
Journal Article
Open access
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MDMaria Luisa Díaz-Bertrana
Maria Luisa Díaz-Bertrana
Stefan DeleuzeStefan Deleuze
Stefan Deleuze
LRLidia Pitti Rios
Lidia Pitti Rios
Marc YesteMarc Yeste
Marc Yeste
MIMoralesi Fariña Inmaculada
Moralesi Fariña Inmaculada
MÁMaria Montserrat Rivera del Álamo
Maria Montserrat Rivera del Álamo
Endometritis is one of the main causes of infertility in mares. In the present study, 363 mares with a history of repetitive infertility, and positive endometrial cytology and/or vaginal discharge were included. An endometrial swab for microbiological purposes plus sensitivity test was obtained from each mare. A positive culture was obtained in 89% of mares. The main isolated genera were Staphylococcus (25.1%), Streptococcus (18.2%), Escherichia (17.3%) and Pseudomonas (12.1%). With regard to species, the most isolated microorganism was Escherichia coli (17.3%), Staphylococcus spp. (15.6%) and Streptococcus spp. (13.5%). Sensitivity tests showed that the most efficient antimicrobial was amikacin (57.3% of cultures), followed by cefoxitin (48.6%) and gentamicin (48.3%). When sensitivity test was analyzed in terms of Gram+ and Gram– bacteria, Gram+ were highly resistant to cephaloridine (77.3% of cultures), apramycin (70.8%) and penicillin (62.3%), whereas Gram– were highly resistant to penicillin (85.8%), followed by cephaloridine (78.9%). In conclusion, the present study shows the most prevalent microorganisms isolated from equine endometritis, which were found to be resistant to β-lactam antimicrobials. Likewise, these results highlight the significance of performing microbiological analyses as well as sensitivity tests prior to applying an antimicrobial therapy.

21 June 2022 in Equine Veterinary Journal
Verified
Journal Article
Closed access
JCJuliette Cognie
Juliette Cognie
SFSandrine Freret
Sandrine Freret
LLLea Lansade
Lea Lansade
CPCeline Parias
Celine Parias
PBPhilippe Barriere
Philippe Barriere
Stefan DeleuzeStefan Deleuze
Stefan Deleuze

6 October 2023 in Animals
Verified
Journal Article
Open access
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SESophie Egyptien
Sophie Egyptien
Stefan DeleuzeStefan Deleuze
Stefan Deleuze
JLJoy Christelle Ledeck
Joy Christelle Ledeck
JPJerôme Ponthier
Jerôme Ponthier
Stallion sperm analysis is indicated for infertility diagnosis, pre-sale expertise, production of fresh or frozen doses, and frozen straw quality control. Various collection methods are described, and numerous assays can be performed on semen. Determining an approach for each of these cases is challenging. This review aims to discuss how to obtain relevant clinical results, answering stallion owners’ concerns. Semen can be collected with an artificial vagina on a phantom or a mare, by electro-ejaculation under anesthesia, or after pharmacological induction. The collection method influences the semen volume and concentration, while the total sperm number depends on the testicular production and collection frequency. In the seminal plasma, acidity, pro-oxidant activity, and some enzymes have repercussions for the semen quality and its conservation. Moreover, non-sperm cells of seminal plasma may impact semen conservation. Motility analysis remains a core parameter, as it is associated with fresh or frozen dose fertility. Computer-assisted motility analyzers have improved repeatability, but the reproducibility between laboratories depends on the settings that are used. Morphology analysis showing spermatozoa defects is useful to understand production and maturation abnormalities. Staining of the spermatozoa is used to evaluate viability, but recent advances in flow cytometry and in fluorochromes enable an evaluation of multiple intracellular parameters. Spermatozoa protein expression already has clinical applications, for example, as a fertility and freezing ability predictor. At present, stallion semen analysis ranges from macroscopic evaluation to assessing spermatozoa proteins. However, clinically, all these data may not be relevant, and the lack of standardization may complicate their interpretation.

9 September 2021 in Frontiers in Veterinary Science
Verified
Journal Article
Open access
Stefan DeleuzeStefan Deleuze
Stefan Deleuze
FBFany Brotcorne
Fany Brotcorne
RPRoland Polet
Roland Polet
GSGede Soma
Gede Soma
GRGoulven Rigaux
Goulven Rigaux
MHMarie-Claude Huynen
Marie-Claude Huynen
Worldwide, primates, and humans increasingly share habitats and often enter in conflict when primates thrive in human-dominated environments, calling for special management measures. Reproductive control is increasingly used to manage population growth but very few monitoring data are available. Therefore, the efficiency and implications of such programs require a careful examination. In the context of a contraception program in wild female long-tailed macaques in Ubud, Bali, conducted over four successive campaigns between 2017 and 2019, including 140 females (i.e., 41.9% of the reproductive females of the population in 2019), modifications of an endoscopic tubectomy procedure, a permanent sterilization method, clinical evaluation of this method, and the post-operative monitoring results of the neutered females after release are described. This surgical approach was applicable for pregnant females: 28.6% of the treated females were pregnant at the time of the surgery. The procedure used a single lateral port to reach and cauterize both oviducts in non-pregnant as well as in early to mid-term pregnant females. Pregnant females nearer to term required a second lateral port to access both oviducts masked by the size of the gravid uterus. Moreover, bipolar thermocauterization was utilized successfully without resection to realize the tubectomy. The average duration of the laparoscopic surgery was 14 min for non-pregnant females and 22 min for pregnant females. Animals were released 3 h 22 min in average following their capture. This short holding time, recommended for free-ranging primates, was made possible by the minimal invasiveness of the sterilization approach. A laparoscopic post-operative evaluation conducted on two patients during the following campaign confirmed that the oviducts were definitely disrupted and no longer patent. Moreover, no new pregnancies in sterilized females were recorded during the 3-year observation period. The survival rate of the treated females 6 months after sterilization was high (96.3%) with no major post-operative complications clinically recorded. Among females that were pregnant during surgery, 81.1% were confirmed to experience term delivery. This study demonstrates the safety and efficiency of endoscopic tubectomy, even for pregnant females, as a mean of wild macaques' population control.

29 August 2021 in Animals
Verified
Journal Article
Open access
PDF file
Gwennan GiraudGwennan Giraud
Gwennan Giraud
SSSebastian Sosa
Sebastian Sosa
Alain HambuckersAlain Hambuckers
Alain Hambuckers
Stefan DeleuzeStefan Deleuze
Stefan Deleuze
IWI Nengah Wandia
I Nengah Wandia
Fany BrotcorneFany Brotcorne
Fany Brotcorne
Contraception is increasingly used to control wild animal populations. However, as reproductive condition influences social interactions in primates, the absence of new offspring could influence the females’ social integration. We studied two groups of wild macaques (Macaca fascicularis) including females recently sterilized in the Ubud Monkey Forest, Indonesia. We used social network analysis to examine female grooming and proximity networks and investigated the role of infant presence on social centrality and group connectivity, while controlling for the fertility status (sterilized N = 14, intact N = 34). We compared the ego networks of females experiencing different nursing conditions (young infant (YI) vs. old infant (OI) vs. non-nursing (NN) females). YI females were less central in the grooming network than other females while being more central in proximity networks, suggesting they could keep proximity within the group to protect their infant from hazards, while decreasing direct grooming interactions, involving potential risks such as kidnapping. The centrality of sterilized and intact females was similar, except for the proximity network where sterilized females had more partners and a better group connectivity. These results confirm the influence of nursing condition in female macaque social networks and did not show any negative short-term effects of sterilization on social integration.

1 January 2022 in Domestic Animal Endocrinology
Verified
Journal Article
Closed access
VFV. Frisée
V. Frisée
GRG. Rigaux
G. Rigaux
PDP. Dufour
P. Dufour
OBO. Barbato
O. Barbato
FBF. Brutinel
F. Brutinel
JPJerôme Ponthier
Jerôme Ponthier