Samuel Buff | University of Lyon (original) (raw)
Other Papers by Samuel Buff
Veterinary anaesthesia and analgesia, Jan 9, 2015
To evaluate the effects and reliability of alfaxalone constant rate infusion (CRI) in comparison ... more To evaluate the effects and reliability of alfaxalone constant rate infusion (CRI) in comparison to isoflurane to maintain anaesthesia in bitches undergoing elective caesarean section. Prospective, randomized, 'blinded' clinical trial. Twenty-two client-owned bitches and 94 puppies. Bitches were randomly assigned to receive an alfaxalone CRI [0.2 mg kg(-1) minute(-1) intravenously (IV), and once the last puppy was delivered, the dose was halved; n = 11] or 2% (vaporizer dial setting) isoflurane (n = 11) for maintenance of anaesthesia. All dogs were induced with alfaxalone (3 mg kg(-1) ) IV. Additional alfaxalone (0.3 mg kg(-1) IV) was administered if the depth of anaesthesia was inadequate and the total dose was calculated. Bitches were mechanically ventilated. Analgesia was administered after the delivery of puppies. Physiological variables were recorded every 5 minutes. The bitches' recovery times were also recorded. Quality of induction and recovery were evaluated. P...
This study investigated the prediction of parturition in queens, as well as the effects of the qu... more This study investigated the prediction of parturition in queens, as well as the effects of the queens' age and weight and the litter size on the accuracy of the prediction. A prospective study was performed in 24 purebred queens of 11 different breeds, all in normal body condition, using radiographic and ultraso-nographic measurements of foetal femoral length (FL) and biparietal diameter (BPD) of foetal skull that apply to different breeds. Pregnant queens with aborted or malformed foetuses were excluded. The examinations were performed up to three times during the second half of pregnancy; litter size was obtained with radiography, and FL and BPD measurements were taken of each foetus using both radiography and ultrasonography. The maximal FL and the transversal BPD were recorded for each foetus. Radiography showed the number of foetuses accurately but did not allow accurate prediction of time of par-turition. However, ultrasonography did establish the best predictive model according to the data with the FL. This model corresponded to the formula Y = 37.864 À 0.193 9 FL + 1.227 9 W À 0.615 9 LS À 0.832 9 A using the FL (10 À1 mm), litter size (LS, number of foetuses per queen) and maternal parameters (weight (W, kg) and age (A, years)). Time to parturition correlated positively with the queen's weight and negatively with her age (P < 0.01). The ultrasonographic FL associated with pregnancy and maternal factors appeared to be an accurate model to predict parturition.
Frontiers in Microbiology, 2016
LecA and LecB tetrameric lectins take part in oligosaccharide-mediated adhesion-processes of Pseu... more LecA and LecB tetrameric lectins take part in oligosaccharide-mediated adhesion-processes of Pseudomonas aeruginosa. Glycomimetics have been designed to block these interactions. The great versatility of P. aeruginosa suggests that the range of application of these glycomimetics could be restricted to genotypes with particular lectin types. The likelihood of having genomic and genetic changes impacting LecA and LecB interactions with glycomimetics such as galactosylated and fucosylated calix[4]arene was investigated over a collection of strains from the main clades of P. aeruginosa. Lectin types were defined, and their ligand specificities were inferred. These analyses showed a loss of lecA among the PA7 clade. Genomic changes impacting lec loci were thus assessed using strains of this clade, and by making comparisons with the PAO1 genome. The lecA regions were found challenged by phage attacks and PAGI-2 (genomic island) integrations. A prophage was linked to the loss of lecA. The lecB regions were found less impacted by such rearrangements but greater lecB than lecA genetic divergences were recorded. Sixteen combinations of LecA and LecB types were observed. Amino acid variations were mapped on PAO1 crystal structures. Most significant changes were observed on LecBPA7, and found close to the fucose binding site. Glycan array analyses were performed with purified LecBPA7. LecBPA7 was found less specific for fucosylated oligosaccharides than LecBPAO1, with a preference for H type 2 rather than type 1, and Lewis(a) rather than Lewis(x). Comparison of the crystal structures of LecBPA7 and LecBPAO1 in complex with Lewis(a) showed these changes in specificity to have resulted from a modification of the water network between the lectin, galactose and GlcNAc residues. Incidence of these modifications on the interactions with calix[4]arene glycomimetics at the cell level was investigated. An aggregation test was used to establish the efficacy of these ligands. Great variations in the responses were observed. Glycomimetics directed against LecB yielded the highest numbers of aggregates for strains from all clades. The use of a PAO1ΔlecB strain confirmed a role of LecB in this aggregation phenotype. Fucosylated calix[4]arene showed the greatest potential for a use in the prevention of P. aeruginosa infections.
Journal of Feline Medicine & Surgery, 2011
An ectopic fetus was discovered in an 18-month-old uniparous queen that was admitted for an elect... more An ectopic fetus was discovered in an 18-month-old uniparous queen that was admitted for an elective ovariectomy. Six months prior she had delivered three healthy kittens. During the preoperative examination, a mass similar in size to a full-term fetus was detected in the abdominal cavity. Ultrasound examination revealed the mass to be an ectopic fetus in the mid-abdominal region. A mummified fetus was removed by laparotomy. No rupture of the uterine wall was visible, but a small necrotic area was present on the left uterine horn, adjacent to the very proximal portion of the uterine horn. The fetus, which was fully developed and covered by a thin membrane, was carefully dissected. Histological examination did not enable us to definitively prove the extra-uterine development of the fetus; however, the ectopic development of the conceptus secondarily expelled into the peritoneal cavity could be assumed.
Immunopharmacology and Immunotoxicology, 2015
The purpose of this study is to define the optimal dose of oral cyclosporine A (CsA) microemulsio... more The purpose of this study is to define the optimal dose of oral cyclosporine A (CsA) microemulsion in newborn swine for transplantation studies and to describe its pharmacokinetics and acute renal effects in short-term administration. Thirteen neonatal pigs were randomized into four groups: one control and three groups with CsA administration at 4, 8 and 12 mg/kg/d for 15 days (D). Blood samples were collected on D 0, 2, 4, 9 and 14 to determine the changes of the CsA trough concentrations, the creatinine (Cr) and blood urea nitrogen (BUN) serum concentrations. On D 14, blood samples were collected every hour from 1 h to 10 h after CsA administration to determine the area under the curve (AUC). On D 15, kidneys were removed for histological analysis. We observed a stabilization of CsA trough concentrations from D 4 to D 14. On D 14, in the three treated groups, CsA trough concentrations were 687 ± 7, 1200 ± 77 and 2211 ± 1030 ng/ml, respectively; AUC (0-10 h) were 6721 ± 51 ng·h/ml in group 4 mg/kg/d, 13431 ± 988 ng·h/ml in group 8 mg/kg/d and 28264 ± 9430 ng·h/ml in group 12 mg/kg/d. Cr concentrations were not significantly different among the four groups; but compared to control group, BUN concentrations of the three treated groups increased significantly. CsA was well tolerated; neither acute, severe adverse event nor renal histological abnormality was observed. In conclusion, a 15-d course of oral CsA treatment ranged from 4 to 12 mg/kg/d is safe for newborn pigs, which need much lower CsA dose than adult pigs to reach comparable trough level and AUC. As immunosuppressive therapy in newborn pigs, we recommend a CsA dose of 4 mg/kg/d to achieve a trough blood concentration between 400 and 800 ng/ml.
Transplant Immunology, 2016
Lymphodepletive agents play important role in different clinical applications or experimental tra... more Lymphodepletive agents play important role in different clinical applications or experimental transplant studies. In order to facilitate preclinical pediatric transplant studies, we have developed the rabbit anti-pig thymocyte globulin (pATG) and studied its effects in neonatal swines. In vitro assays showed that pATG can bind to lymphocytes and neutrophils in a dose-dependent manner and lyse peripheral blood mononuclear cells by apoptosis and complement-dependent cytotoxicity. In vivo, pATG as a monotherapy was administered at different doses (2.5, 5, 20, 40 and 80mg/kg) in newborn pigs. Results showed that pATG induced a dose-dependent but transient T-cell depletion in peripheral blood. Lymphodepletion was also observed in lymph nodes, spleen and thymus. Pharmacokinetic studies showed dose-related cell-bound pATG on lymphocytes, as well as the presence of free pATG in the serum. Both cell-bound and free pATG levels decreased gradually after administration. Interestingly, adjuvant mycophenolate mofetil (MMF) given at 1g/m(2)/day for 1week successfully maintained pATG-induced T-cell depletion. In conclusion, pATG administration can cause transient T-cell depletion in neonatal pigs and this effect can be maintained by MMF. Therefore, we have developed an original immunosuppressive regimen that can be used for transplantation studies in swine model.
Veterinary Immunology and Immunopathology, 2016
In veterinary medicine, therapeutic mesenchymal stromal cells (MSC) have been traditionally isola... more In veterinary medicine, therapeutic mesenchymal stromal cells (MSC) have been traditionally isolated from adult bone marrow or adipose tissue. Neonatal tissues, normally discarded at birth from all species have become an alternative source of cells for regenerative medicine in the human clinic. These cells have been described as being more primitive, proliferative and immunosuppressive than their adult counterparts. Our objective was to examine if this phenomena holds true in dogs. Little information exists regarding canine neonatal MSC characterisation. In this study, we were able to both isolate, phenotype and assess the differentiation and immunomodulatory properties of MSC from canine foetal adnexa allowing us to compare their characteristics to their more well-known bone marrow (BM) cousins. Neonatal tissues, including amnion (AM), placenta (PL), and umbilical cord matrix (UCM) were collected from 6 canine caesarean sections. Primary cells were expanded in vitro for 5 consecutive passages and their proliferation measured. BM-MSC were isolated from 5 control dogs euthanised from other studies and grown in vitro using an identical protocol. All MSC lines were systematically evaluated for their ability to differentiate into 3 mesodermal lineages (adipocyte, osteocyte and chondrocyte) and phenotyped by cytometry and qPCR. In addition, the enzymatic activity of the key immunomodulatory marker indoleamine 2,3-dioxygenase (IDO) was evaluated for each MSC line. MSC displaying a fibroblastic appearance were successfully grown from all neonatal tissues. PL-MSC exhibited significantly higher proliferation rates than AM- and UCM-MSC (p=0.05). Cytometric analysis showed that all MSC express CD90, CD29, and CD44, while no expression of CD45, CD34 and MHC2 was detected. Molecular profiling showed expression of CD105 and CD73 in all MSC. Low levels of SOX2 mRNA was observed in all MSC, while neither NANOG, nor OCT4 were detected. All MSC differentiate into 3 mesodermal lineages. Following inflammatory stimulation, the activity of the immunomodulatory enzyme IDO was significantly higher in neonatal MSC compared to BM-MSC (p=0.009). Our results show that canine foetal adnexa cells share very similar properties to their adult equivalents but upon stimulation show significantly higher IDO immunomodulatory activity. Further studies will be needed to confirm the potential therapeutic benefits of these cells.
![Research paper thumbnail of [Follicular morphology after ovarian cortex cryopreservation in the rabbit doe(Oryctolagus cuniculus)]](https://attachments.academia-assets.com/49750962/thumbnails/1.jpg)
](Gynécologie, obstétrique & fertilité, 2005
To compare the effects of two cryoprotective agents (DMSO and 1,2-PROH) used at two concentration... more To compare the effects of two cryoprotective agents (DMSO and 1,2-PROH) used at two concentrations (1,5 and 2 M) on the morphology of small ovarian cortex follicles in doe. Ovarian cortexes (n=40) were frozen in TCM199+10% FCS medium added to 1.5 or 2 M of DMSO or 1,2-PROH. Two controls were realized (fresh and frozen without cryoprotectant). The equilibration in cryoprotective solutions before freezing, and the elimination of the cryoprotective agents after thawing, was performed step by step. The effects induced by cryopreservation were evaluated by histological examination. Fresh ovarian tissue showed 68.6% of intact follicles. After freezing, only 1.5 M of 1,2-PROH preserved 48.0% of normal follicles, with no significant difference compared to the fresh control. The proportion of follicles without morphological defect observed after cryopreservation with DMSO was significantly reduced (respectively 28.8 and 34.8% for 1,5 and 2 M of DMSO). Our results suggest that 1,2-PROH is a m...
Journal of reproduction and fertility. Supplement, 2001
A new kit (ReproCHEK RELAXIN) intended for the diagnosis of pregnancy in bitches is now available... more A new kit (ReproCHEK RELAXIN) intended for the diagnosis of pregnancy in bitches is now available for veterinary use. This assay measures relaxin concentrations in plasma and whole blood samples, and the presence of significant amounts of relaxin is indicative of pregnancy. A clinical trial was carried out to evaluate the performance of the test. Serial blood samples were collected on alternate days, and relaxin concentrations were determined from day 15 to day 35 after the LH surge (estimated by progesterone concentrations). Pregnancy was confirmed using ultrasonography. At the end of pregnancy, both the day of whelping and the size of the litter were recorded. Pregnancy was established in 61 bitches. The day that pregnancy was detected using the relaxin assay ranged from day 19 to day 28 after the LH surge and had a mean (+/- SD) of 25.4 +/- 2.5 days. The day of parturition was taken as a reference point, and pregnancy was detected from -46 to -38 days (mean -40.2 +/- 2.4 days) be...
Veterinary Clinical Pathology, 2012
Reproduction in domestic animals = Zuchthygiene, 2014
An eight-month-old female dog presented with ambiguous external genitalia. A thorough clinical ex... more An eight-month-old female dog presented with ambiguous external genitalia. A thorough clinical examination together with various imaging techniques and a histology examination showed the presence of two testicles linked to both the Mullerian and Wolffian ducts. The discovery of the 78,XX SRY-negative karyotype led to the diagnosis of incoherence between the chromosomal and gonadal sex, which is typical for a 78,XX testicular disorder of sex development. Our case was unique because the testicles were still located in their normal scrotal position, whereas the literature contains reports of the presence of cryptorchid testicles in this karyotype setting. To our knowledge, this is the first case that describes an SRY-negative 78,XX testicular disorder of sex development with bilateral scrotal testicles.
The Veterinary Journal, 2013
Although most French dogs are correctly vaccinated against leptospirosis with inactivated strains... more Although most French dogs are correctly vaccinated against leptospirosis with inactivated strains of canicola and icterohaemorrhagiae, the disease is still very prevalent in France raising the question of whether the vaccines used require updating. The aim of the present study was to provide serological data regarding circulation of the Leptospira serovars: grippotyphosa, bratislava, pomona and mozdok, which are contained in vaccines available in other parts of the world and which could be rapidly adapted for France. Results indicated that the epidemiology was consistent with the circulation of Leptospira belonging to the serogroups Australis and Grippotyphosa and that the case to support the inclusion of either pomona or mozdok in a dog vaccine for France was weak.
Conference Presentations by Samuel Buff
Veterinary anaesthesia and analgesia, Jan 9, 2015
To evaluate the effects and reliability of alfaxalone constant rate infusion (CRI) in comparison ... more To evaluate the effects and reliability of alfaxalone constant rate infusion (CRI) in comparison to isoflurane to maintain anaesthesia in bitches undergoing elective caesarean section. Prospective, randomized, 'blinded' clinical trial. Twenty-two client-owned bitches and 94 puppies. Bitches were randomly assigned to receive an alfaxalone CRI [0.2 mg kg(-1) minute(-1) intravenously (IV), and once the last puppy was delivered, the dose was halved; n = 11] or 2% (vaporizer dial setting) isoflurane (n = 11) for maintenance of anaesthesia. All dogs were induced with alfaxalone (3 mg kg(-1) ) IV. Additional alfaxalone (0.3 mg kg(-1) IV) was administered if the depth of anaesthesia was inadequate and the total dose was calculated. Bitches were mechanically ventilated. Analgesia was administered after the delivery of puppies. Physiological variables were recorded every 5 minutes. The bitches' recovery times were also recorded. Quality of induction and recovery were evaluated. P...
This study investigated the prediction of parturition in queens, as well as the effects of the qu... more This study investigated the prediction of parturition in queens, as well as the effects of the queens' age and weight and the litter size on the accuracy of the prediction. A prospective study was performed in 24 purebred queens of 11 different breeds, all in normal body condition, using radiographic and ultraso-nographic measurements of foetal femoral length (FL) and biparietal diameter (BPD) of foetal skull that apply to different breeds. Pregnant queens with aborted or malformed foetuses were excluded. The examinations were performed up to three times during the second half of pregnancy; litter size was obtained with radiography, and FL and BPD measurements were taken of each foetus using both radiography and ultrasonography. The maximal FL and the transversal BPD were recorded for each foetus. Radiography showed the number of foetuses accurately but did not allow accurate prediction of time of par-turition. However, ultrasonography did establish the best predictive model according to the data with the FL. This model corresponded to the formula Y = 37.864 À 0.193 9 FL + 1.227 9 W À 0.615 9 LS À 0.832 9 A using the FL (10 À1 mm), litter size (LS, number of foetuses per queen) and maternal parameters (weight (W, kg) and age (A, years)). Time to parturition correlated positively with the queen's weight and negatively with her age (P < 0.01). The ultrasonographic FL associated with pregnancy and maternal factors appeared to be an accurate model to predict parturition.
Frontiers in Microbiology, 2016
LecA and LecB tetrameric lectins take part in oligosaccharide-mediated adhesion-processes of Pseu... more LecA and LecB tetrameric lectins take part in oligosaccharide-mediated adhesion-processes of Pseudomonas aeruginosa. Glycomimetics have been designed to block these interactions. The great versatility of P. aeruginosa suggests that the range of application of these glycomimetics could be restricted to genotypes with particular lectin types. The likelihood of having genomic and genetic changes impacting LecA and LecB interactions with glycomimetics such as galactosylated and fucosylated calix[4]arene was investigated over a collection of strains from the main clades of P. aeruginosa. Lectin types were defined, and their ligand specificities were inferred. These analyses showed a loss of lecA among the PA7 clade. Genomic changes impacting lec loci were thus assessed using strains of this clade, and by making comparisons with the PAO1 genome. The lecA regions were found challenged by phage attacks and PAGI-2 (genomic island) integrations. A prophage was linked to the loss of lecA. The lecB regions were found less impacted by such rearrangements but greater lecB than lecA genetic divergences were recorded. Sixteen combinations of LecA and LecB types were observed. Amino acid variations were mapped on PAO1 crystal structures. Most significant changes were observed on LecBPA7, and found close to the fucose binding site. Glycan array analyses were performed with purified LecBPA7. LecBPA7 was found less specific for fucosylated oligosaccharides than LecBPAO1, with a preference for H type 2 rather than type 1, and Lewis(a) rather than Lewis(x). Comparison of the crystal structures of LecBPA7 and LecBPAO1 in complex with Lewis(a) showed these changes in specificity to have resulted from a modification of the water network between the lectin, galactose and GlcNAc residues. Incidence of these modifications on the interactions with calix[4]arene glycomimetics at the cell level was investigated. An aggregation test was used to establish the efficacy of these ligands. Great variations in the responses were observed. Glycomimetics directed against LecB yielded the highest numbers of aggregates for strains from all clades. The use of a PAO1ΔlecB strain confirmed a role of LecB in this aggregation phenotype. Fucosylated calix[4]arene showed the greatest potential for a use in the prevention of P. aeruginosa infections.
Journal of Feline Medicine & Surgery, 2011
An ectopic fetus was discovered in an 18-month-old uniparous queen that was admitted for an elect... more An ectopic fetus was discovered in an 18-month-old uniparous queen that was admitted for an elective ovariectomy. Six months prior she had delivered three healthy kittens. During the preoperative examination, a mass similar in size to a full-term fetus was detected in the abdominal cavity. Ultrasound examination revealed the mass to be an ectopic fetus in the mid-abdominal region. A mummified fetus was removed by laparotomy. No rupture of the uterine wall was visible, but a small necrotic area was present on the left uterine horn, adjacent to the very proximal portion of the uterine horn. The fetus, which was fully developed and covered by a thin membrane, was carefully dissected. Histological examination did not enable us to definitively prove the extra-uterine development of the fetus; however, the ectopic development of the conceptus secondarily expelled into the peritoneal cavity could be assumed.
Immunopharmacology and Immunotoxicology, 2015
The purpose of this study is to define the optimal dose of oral cyclosporine A (CsA) microemulsio... more The purpose of this study is to define the optimal dose of oral cyclosporine A (CsA) microemulsion in newborn swine for transplantation studies and to describe its pharmacokinetics and acute renal effects in short-term administration. Thirteen neonatal pigs were randomized into four groups: one control and three groups with CsA administration at 4, 8 and 12 mg/kg/d for 15 days (D). Blood samples were collected on D 0, 2, 4, 9 and 14 to determine the changes of the CsA trough concentrations, the creatinine (Cr) and blood urea nitrogen (BUN) serum concentrations. On D 14, blood samples were collected every hour from 1 h to 10 h after CsA administration to determine the area under the curve (AUC). On D 15, kidneys were removed for histological analysis. We observed a stabilization of CsA trough concentrations from D 4 to D 14. On D 14, in the three treated groups, CsA trough concentrations were 687 ± 7, 1200 ± 77 and 2211 ± 1030 ng/ml, respectively; AUC (0-10 h) were 6721 ± 51 ng·h/ml in group 4 mg/kg/d, 13431 ± 988 ng·h/ml in group 8 mg/kg/d and 28264 ± 9430 ng·h/ml in group 12 mg/kg/d. Cr concentrations were not significantly different among the four groups; but compared to control group, BUN concentrations of the three treated groups increased significantly. CsA was well tolerated; neither acute, severe adverse event nor renal histological abnormality was observed. In conclusion, a 15-d course of oral CsA treatment ranged from 4 to 12 mg/kg/d is safe for newborn pigs, which need much lower CsA dose than adult pigs to reach comparable trough level and AUC. As immunosuppressive therapy in newborn pigs, we recommend a CsA dose of 4 mg/kg/d to achieve a trough blood concentration between 400 and 800 ng/ml.
Transplant Immunology, 2016
Lymphodepletive agents play important role in different clinical applications or experimental tra... more Lymphodepletive agents play important role in different clinical applications or experimental transplant studies. In order to facilitate preclinical pediatric transplant studies, we have developed the rabbit anti-pig thymocyte globulin (pATG) and studied its effects in neonatal swines. In vitro assays showed that pATG can bind to lymphocytes and neutrophils in a dose-dependent manner and lyse peripheral blood mononuclear cells by apoptosis and complement-dependent cytotoxicity. In vivo, pATG as a monotherapy was administered at different doses (2.5, 5, 20, 40 and 80mg/kg) in newborn pigs. Results showed that pATG induced a dose-dependent but transient T-cell depletion in peripheral blood. Lymphodepletion was also observed in lymph nodes, spleen and thymus. Pharmacokinetic studies showed dose-related cell-bound pATG on lymphocytes, as well as the presence of free pATG in the serum. Both cell-bound and free pATG levels decreased gradually after administration. Interestingly, adjuvant mycophenolate mofetil (MMF) given at 1g/m(2)/day for 1week successfully maintained pATG-induced T-cell depletion. In conclusion, pATG administration can cause transient T-cell depletion in neonatal pigs and this effect can be maintained by MMF. Therefore, we have developed an original immunosuppressive regimen that can be used for transplantation studies in swine model.
Veterinary Immunology and Immunopathology, 2016
In veterinary medicine, therapeutic mesenchymal stromal cells (MSC) have been traditionally isola... more In veterinary medicine, therapeutic mesenchymal stromal cells (MSC) have been traditionally isolated from adult bone marrow or adipose tissue. Neonatal tissues, normally discarded at birth from all species have become an alternative source of cells for regenerative medicine in the human clinic. These cells have been described as being more primitive, proliferative and immunosuppressive than their adult counterparts. Our objective was to examine if this phenomena holds true in dogs. Little information exists regarding canine neonatal MSC characterisation. In this study, we were able to both isolate, phenotype and assess the differentiation and immunomodulatory properties of MSC from canine foetal adnexa allowing us to compare their characteristics to their more well-known bone marrow (BM) cousins. Neonatal tissues, including amnion (AM), placenta (PL), and umbilical cord matrix (UCM) were collected from 6 canine caesarean sections. Primary cells were expanded in vitro for 5 consecutive passages and their proliferation measured. BM-MSC were isolated from 5 control dogs euthanised from other studies and grown in vitro using an identical protocol. All MSC lines were systematically evaluated for their ability to differentiate into 3 mesodermal lineages (adipocyte, osteocyte and chondrocyte) and phenotyped by cytometry and qPCR. In addition, the enzymatic activity of the key immunomodulatory marker indoleamine 2,3-dioxygenase (IDO) was evaluated for each MSC line. MSC displaying a fibroblastic appearance were successfully grown from all neonatal tissues. PL-MSC exhibited significantly higher proliferation rates than AM- and UCM-MSC (p=0.05). Cytometric analysis showed that all MSC express CD90, CD29, and CD44, while no expression of CD45, CD34 and MHC2 was detected. Molecular profiling showed expression of CD105 and CD73 in all MSC. Low levels of SOX2 mRNA was observed in all MSC, while neither NANOG, nor OCT4 were detected. All MSC differentiate into 3 mesodermal lineages. Following inflammatory stimulation, the activity of the immunomodulatory enzyme IDO was significantly higher in neonatal MSC compared to BM-MSC (p=0.009). Our results show that canine foetal adnexa cells share very similar properties to their adult equivalents but upon stimulation show significantly higher IDO immunomodulatory activity. Further studies will be needed to confirm the potential therapeutic benefits of these cells.
Gynécologie, obstétrique & fertilité, 2005
To compare the effects of two cryoprotective agents (DMSO and 1,2-PROH) used at two concentration... more To compare the effects of two cryoprotective agents (DMSO and 1,2-PROH) used at two concentrations (1,5 and 2 M) on the morphology of small ovarian cortex follicles in doe. Ovarian cortexes (n=40) were frozen in TCM199+10% FCS medium added to 1.5 or 2 M of DMSO or 1,2-PROH. Two controls were realized (fresh and frozen without cryoprotectant). The equilibration in cryoprotective solutions before freezing, and the elimination of the cryoprotective agents after thawing, was performed step by step. The effects induced by cryopreservation were evaluated by histological examination. Fresh ovarian tissue showed 68.6% of intact follicles. After freezing, only 1.5 M of 1,2-PROH preserved 48.0% of normal follicles, with no significant difference compared to the fresh control. The proportion of follicles without morphological defect observed after cryopreservation with DMSO was significantly reduced (respectively 28.8 and 34.8% for 1,5 and 2 M of DMSO). Our results suggest that 1,2-PROH is a m...
Journal of reproduction and fertility. Supplement, 2001
A new kit (ReproCHEK RELAXIN) intended for the diagnosis of pregnancy in bitches is now available... more A new kit (ReproCHEK RELAXIN) intended for the diagnosis of pregnancy in bitches is now available for veterinary use. This assay measures relaxin concentrations in plasma and whole blood samples, and the presence of significant amounts of relaxin is indicative of pregnancy. A clinical trial was carried out to evaluate the performance of the test. Serial blood samples were collected on alternate days, and relaxin concentrations were determined from day 15 to day 35 after the LH surge (estimated by progesterone concentrations). Pregnancy was confirmed using ultrasonography. At the end of pregnancy, both the day of whelping and the size of the litter were recorded. Pregnancy was established in 61 bitches. The day that pregnancy was detected using the relaxin assay ranged from day 19 to day 28 after the LH surge and had a mean (+/- SD) of 25.4 +/- 2.5 days. The day of parturition was taken as a reference point, and pregnancy was detected from -46 to -38 days (mean -40.2 +/- 2.4 days) be...
Veterinary Clinical Pathology, 2012
Reproduction in domestic animals = Zuchthygiene, 2014
An eight-month-old female dog presented with ambiguous external genitalia. A thorough clinical ex... more An eight-month-old female dog presented with ambiguous external genitalia. A thorough clinical examination together with various imaging techniques and a histology examination showed the presence of two testicles linked to both the Mullerian and Wolffian ducts. The discovery of the 78,XX SRY-negative karyotype led to the diagnosis of incoherence between the chromosomal and gonadal sex, which is typical for a 78,XX testicular disorder of sex development. Our case was unique because the testicles were still located in their normal scrotal position, whereas the literature contains reports of the presence of cryptorchid testicles in this karyotype setting. To our knowledge, this is the first case that describes an SRY-negative 78,XX testicular disorder of sex development with bilateral scrotal testicles.
The Veterinary Journal, 2013
Although most French dogs are correctly vaccinated against leptospirosis with inactivated strains... more Although most French dogs are correctly vaccinated against leptospirosis with inactivated strains of canicola and icterohaemorrhagiae, the disease is still very prevalent in France raising the question of whether the vaccines used require updating. The aim of the present study was to provide serological data regarding circulation of the Leptospira serovars: grippotyphosa, bratislava, pomona and mozdok, which are contained in vaccines available in other parts of the world and which could be rapidly adapted for France. Results indicated that the epidemiology was consistent with the circulation of Leptospira belonging to the serogroups Australis and Grippotyphosa and that the case to support the inclusion of either pomona or mozdok in a dog vaccine for France was weak.
Reproduction in Domestic Animals
Non-surgical transfer of embryos to mares induced into prolonged dioestrus by transrectal manuall... more Non-surgical transfer of embryos to mares induced into prolonged dioestrus by transrectal manually rupture of the conceptus after liberation of the ‘maternal recognition of pregnancy’ signal resulted in no pregnancies, suggesting an inadequate endometrial environment for conceptus development. The aim of the present study was to compare the ultrastructure of the endometrial glands in mares induced to pass into prolonged dioestrus with those in mares at an equivalent stage of gestation. Endometrial biopsies were collected on 8 mares on day 26 of
pregnancy, 8 days after manual rupture of a day 18 conceptus and on day 8 of
dioestrus. Samples were processed in 2% glutaraldehyde and fixed in OsO4 1% (both in 0.1M cacodylate buffer) before progressive dehydration in propylene oxide. Sections were contrasted with uranyle acetate/lead citrate. Descriptive statistics and an analysis of covariance with the number of vacuoles as a function of ‘stage’ and ‘mare’ were performed. The number of vacuoles per glandular cell present 8 days after rupturing the conceptus was significantly (p<0.001) lower than those at the ‘equivalent stage of gestation’ (6.53 versus 12.70) and within the same quantity range as in dioestrus. Thus, it was concluded that the presence of a conceptus in the uterus stimulates the secretion of histotroph secretions by the glandular epithelium. For this reason, the term ‘prolonged dioestrus’, rather than ‘pseudopregnancy’, would seem more appropriate to describe a non-pregnant mare that exhibits failure of cyclical luteolysis.
Reproduction in Domestic Animals
Reproduction in Domestic Animals
Gynécologie Obstétrique & Fertilité, 2005
Reproduction in Domestic Animals
A new in-clinic lateral flow device (Witness LH, Synbiotics) was recently designed to detect lute... more A new in-clinic lateral flow device (Witness LH, Synbiotics) was recently designed to detect luteinizing hormone (LH) in dogs and cats. A preliminary study was conducted to evaluate the interest of this rapid lateral flow device with bovine serum samples. Eight cyclic non-lactating cows were synchronized with a double injection of prostaglandin-F2 alpha (PgF2α , Estrumate 3mL i.m., Schering-Plough) 11 days apart and checked for estrous behavior by visual observation during 5 days starting the day after the second injection of PgF2α. Cows were considered to be in estrus when they stood when being mounted by an herd mate. The ovaries of each animal were scanned daily using a real-time ultrasonography with a 7.5 MHz transrectal linear probe to follow ovarian activity. Blood samples were collected every 6 hrs following the second injection of PgF2α. LH concentrations were measured by ELISA (Maurel et al., proceedings AETE, 1991) and determined semi quantitatively with Witness LH (as negative, intermediate and positive results). The overall correlation coefficient between LH concentration and Witness LH result was =0.738 (Spearman’s rank coefficient). These results confirm that Witness LH can be used for rapid detection of LH peaks in bovine serum samples and may be used as an additional tool to improve heat detection before AI.
SFT/ACT Annual Conference & Symposium
Introduction. Several studies indicate correlations between the age of the conceptus and ultrason... more Introduction. Several studies indicate correlations between the age of the conceptus and ultrasonographic measurements during the first 30 days of queen pregnancy (using the diameter of the gestational sac and the crown-rump length of the embryo) and during the second half of pregnancy (using the diameter of the foetal abdomen, the biparietal diameter of the foetal skull and the diameter of the foetal stomach). Other studies predict parturition timing by using the bi-parietal diameter and the deep portion of diencephalo-telencephalic vesicle but the interval of prediction isn’t precise enough. The aim of the present study is to predict more precisely the onset of parturition timing using new radiographic and ultrasonograhic measurements. The effects of the litter size, the weight and the age the queen on the accuracy of the prediction were also investigated.
Material and Methods. A prospective study was performed in 24 purebred queens (11 different breeds, 1 to 8 individuals per breed) weighting from 2.7 to 5.8 kg, and aged from 0.7 to 6 years. Litter sizes were from 1 to 8 kittens, with 12 first-rank pregnancies. Aborted parturitions and malformed foetus were excluded from the study. Ultrasonographic and radiographic exams were performed by an ECVDI Diplomate. Cats were scanned in dorsal recumbency, without sedation, from 35 days before parturition to the day of term. The measurements were performed once, twice or three times on each queen, using a micro-convex probe (Esaote, 8-12 MHz). For each foetus, the maximal length of the femur and the transversal biparietal diameter were measured from fixed images and were recorded. Lateral and ventrodorsal digital radiographs were realized to determine the litter size and to measure the maximal femur length and the biparietal diameter. The parturition time was estimated using linear mixed-effects models (with the length of the femur or the biparietal diameter, and the individual parameters of the queens as fixed effect and the queens as a random effect). The linear mixed model was chosen because of random effects (several foetuses for one queen and a few paired measurements) and fixed effects.
Results. Concerning ultrasonographic measurements, parameters selected for the best linear regression were the femur length (x1), the weight of the queen before pregnancy (x2), the litter size (x3) and the age of the queen (x4). The formula to predict the number of days before parturition was: y = 37.864 - 0.193×x1 + 1.227×x2 - 0.615×x3 - 0.832×x4. The 70% prediction level was y ± 1.6 days. All the fixed effects were significant. Concerning radiographic measurements, a simple linear model was chosen: the adjusted R-squared obtained with femur length or biparietal diameter were significantly different from 1. The duration of the gestation was increased with the weight of the queen before mating (p<0.01). The onset of the parturition was shorter when the femur was longer, and when the queen was older (p<0.01).
Conclusion. Radiography is essential to count the number of foetuses but is not accurate to predict parturition. Ultrasonographic measurement of the foetal femur length in relation to the queen’s weight and age, and the number of foetuses allows predicting the onset of parturition in cats after 40 days of gestation. The random effects are very important to consider, but they could be reduced by adding more pregnant females to the study with a higher power of the study; this would allow adding new parameters in the regression. This study confirms that models using the length of the femur give a more precise prediction of the onset of parturition than models using biparietal diameter; furthermore, it is easier to measure the length of the femur than the biparietal diameter.
The aim of this study was to predict both the accurate onset of parturition, using ultrasonograph... more The aim of this study was to predict both the accurate onset of parturition, using ultrasonographic measurements of the femur, and the kitten’s birth weight. For this purpose, a prospective study was performed in 24 purebred queens with normal pregnancy.
Cats were scanned from 35 days before parturition to the day of term, using a micro-convex probe (8-12 MHz). Lateral and ventrodorsal radiographs were used to determine the litter size. For each foetus, the maximal femur length and the transversal biparietal diameter were measured. The parturition time and the kitten’s birth weight were estimated using linear mixed-effects models on R software because of random effects (several foetuses for one queen and a few paired measurements) and fixed effects (litter size, weight, wither height and age).
The best linear regression of the parturition time was y = 37.864 - 0.193×x1 + 1.227×x2 - 0.615×x3 - 0.832×x4. The variables were the femur length (x1), the weight of the queen before pregnancy (x2), the litter size (x3) and the age of the queen (x4). The 70% prediction level was y ± 1.6 days. The kitten’s birth weight was correlated to the calculated femur length at birth (x6) and the wither height (x5). The estimated weight (w) was determined using the following formula: log (w) = 0.692+ 0.011×x5 + 0.005×x6. The best predicted level was obtained using femur length as compared to biparietal diameter. The duration of the gestation was increased with the weight of the queen before mating (P<0.01). The onset of the parturition was sooner when the femur was longer, and when the queen was older (P<0.01). By predicting the kitten’s weight at birth, the model is also informative for their prognosis for life.
Summa Animali Da Compagnia, 2009
Le Point Veterinaire Revue D Enseignement Post Universitaie Et De Formation Permanente, 2008
Le Point Veterinaire, 2013
Le Point Veterinaire Revue D Enseignement Post Universitaie Et De Formation Permanente, 2009
Le Point Veterinaire Revue D Enseignement Post Universitaie Et De Formation Permanente, 2008
Point Veterinaire Vol 032 221, Dec 1, 2001
Le Point Veterinaire Revue D Enseignement Post Universitaie Et De Formation Permanente, 2001
Le Point Veterinaire Revue D Enseignement Post Universitaie Et De Formation Permanente, 2001
Le Point Veterinaire Revue D Enseignement Post Universitaie Et De Formation Permanente, 2009
Le Point Veterinaire Revue D Enseignement Post Universitaie Et De Formation Permanente, 2001
Pratique Medicale Chirurgicale De L Animal De Compagnie Personnel Soignant, 2001
Reproduction, Fertility and Development, 2012
Theriogenology, 2010
The cryopreservation of oocytes is valuable for the preservation of women&amp;amp;amp;amp... more The cryopreservation of oocytes is valuable for the preservation of women&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s fertility and might also be an interesting tool to preserve animal genetic biodiversity but it is not often used because of the very poor fertility recovered after thawing, especially in rabbit species. The objective of our study was to evaluate the effect of slow-freezing and vitrification on the structural integrity of ovulated rabbit oocytes, their ATP contents, and their developmental competence. Results show that, whatever the method is used, cryopreservation has a dramatic effect on the metabolic integrity, the structural integrity, and the developmental ability of the oocytes. Vitrification and slow freezing both impair the rabbit oocytes viability after thawing but the processes act differently. Further studies are needed to improve the cryopreservation techniques in rabbit species. Moreover, we underlined that morphology and maintenance of the structural integrity of the oocytes are not suitable enough to assess the potential for further development of cryopreserved M(II) oocytes. The assessment of ATP metabolism allows efficient evaluation of the viability of the frozen or vitrified oocytes. It should be used in addition to parthenogenesis to better assess the potential for further development.
Fertility and Sterility, 2008
Reproduction in Domestic Animals
Current Frontiers in Cryopreservation, 2012
Reproduction in Domestic Animals