microRNAs are differentially expressed in equine plasma of horses with osteoarthritis and osteochondritis dissecans versus control horses.

Osteoarthritis (OA) is a leading cause of lameness in horses with no effective disease-modifying treatment and challenging early diagnosis. OA is considered a disease of the joint involving the articular cartilage, subchondral bone, synovial membrane, and ligaments. Osteochondritis dissecans (OCD) is a joint disease consisting of focal defects in the osteochondral unit which may progress to OA later in life. MicroRNAs (miRNAs) have been recognized as small non-coding RNAs that regulate a variety of biological processes and have been detected in biological fluids. MiRNAs are currently investigated for their utility as biomarkers and druggable targets for a variety of diseases. The current study hypothesizes that miRNA profiles can be used to actively monitor joint health and differences in miRNA profiles will be found in healthy vs diseased joints and that differences will be detectable in blood plasma of tested horses. Five horses with OA, OCD, and 4 controls (C) had blood plasma and synovial fluid collected. Total RNA, including miRNA was isolated before generating miRNA libraries from the plasma of the horses. Libraries were sequenced at the Schroeder Arthritis Institute (Toronto). Differential expression analysis was done using DESeq2 and validated using ddPCR. KEGG pathway analysis was done using mirPath v.3 (Diana Tools). 57 differentially expressed miRNAs were identified in OA vs C plasma, 45 differentially expressed miRNAs in OC vs C plasma, and 21 differentially expressed miRNAs in OA vs OCD plasma. Notably, miR-140-5p expression was observed to be elevated in OA synovial fluid suggesting that miR-140-5p may serve as a protective marker early on to attenuate OA progression. KEGG pathway analysis of differentially expressed plasma miRNAs showed relationships with glycan degradation, glycosaminoglycan degradation, and hippo signaling pathway. Interestingly, ddPCR was unable to validate the NGS data suggesting that isomiRs may play an integral role in miRNA expression when assessed using NGS technologies.

Retrospective study of perioperative antimicrobial use in horses undergoing elective laparoscopy at a single institution.

Antimicrobial stewardship has shown significant development in recent years. Perioperative prophylaxis accounts for a substantial volume of antimicrobial use and is a field in which improvements can likely be made. The objective of this study was to evaluate practices associated with perioperative antimicrobial use in equine elective laparoscopy at a single institution over a 21-year period and to determine whether antimicrobial therapy influenced the occurrence of postoperative complications. Medical records of horses that underwent elective laparoscopy at a teaching hospital from January 2000 to September 2021 were reviewed. Data obtained included signalment, surgeon, type and duration of procedure, perioperative antimicrobial use, and intraoperative and postoperative complications. Exact univariate logistic regression was used to explore the association between possible risk factors and occurrence of postoperative complications, as well as the association between year of presentation and time of antimicrobial administration. Duration of surgery was log-transformed to meet assumption of normality, followed by analysis of variance (ANOVA) to compare mean surgery time per procedure and postoperative complications. Significance was set at P < 0.05. Sixty horses met the inclusion criteria. All horses received antimicrobial prophylaxis, but none received intraoperative redosing. Only 13 horses (26%) received antimicrobials within 60 min of the first incision. Time of administration improved with each year of the study (P = 0.005). Only 17 horses (28%) received antimicrobials for less than 24 h, but median duration of antimicrobial therapy was 1.25 d (range: 0.25 to 10 d). Antimicrobial use practices at this institution differed from general recommendations for optimal perioperative prophylaxis, which suggests that intervention is required.

L'antibiogouvernance a connu un développement significatif ces dernières années. La prophylaxie peropératoire représente un volume important d'utilisation d'antimicrobiens et constitue un domaine dans lequel des améliorations peuvent probablement être apportées. L'objectif de cette étude était d'évaluer les pratiques associées à l'utilisation peropératoire d'antimicrobiens en laparoscopie élective équine dans un seul établissement sur une période de 21 ans et de déterminer si le traitement antimicrobien influençait la survenue de complications postopératoires. Les dossiers médicaux des chevaux ayant subi une laparoscopie élective dans un centre hospitalier universitaire de janvier 2000 à septembre 2021 ont été examinés. Les données obtenues comprenaient le signalement, le chirurgien, le type et la durée de la procédure, l'utilisation d'antimicrobiens peropératoires et les complications intra-opératoires et postopératoires. Une régression logistique univariée exacte a été utilisée pour explorer l'association entre les facteurs de risque possibles et la survenue de complications postopératoires, ainsi que l'association entre l'année de présentation et le moment de l'administration des antimicrobiens. La durée de la chirurgie a été transformée en log pour répondre à l'hypothèse de normalité, suivie d'une analyse de variance (ANOVA) pour comparer la durée moyenne de la chirurgie par procédure et les complications postopératoires. La signification a été fixée à P < 0,05. Soixante chevaux répondaient aux critères d'inclusion. Tous les chevaux ont reçu une prophylaxie antimicrobienne, mais aucun n'a reçu de dose supplémentaire durant la chirurgie. Seuls 13 chevaux (26 %) ont reçu des antimicrobiens dans les 60 minutes suivant la première incision. Le temps d'administration s'est amélioré avec chaque année d'étude (P = 0,005). Seulement 17 chevaux (28 %) ont reçu des antimicrobiens pendant moins de 24 heures, mais la durée médiane du traitement antimicrobien était de 1,25 jour (plage : 0,25 à 10 jours). Les pratiques d'utilisation des antimicrobiens dans cet établissement différaient des recommandations générales pour une prophylaxie peropératoire optimale, ce qui suggère qu'une intervention est nécessaire.(Traduit par Docteur Serge Messier).

Anoplasty and rectovaginal fistula repair in a gilt with atresia ani: A case report.

A 2-year-old female Vietnamese potbellied pig was referred to the Large Animal Teaching Hospital at the Ontario Veterinary College for anoplasty and rectovaginal fistula repair. The presence of atresia ani and rectovaginal fistula had been previously diagnosed. Contrast radiography was used to confirm the diagnosis and determine the position of the fistula and terminal rectum. Under general anesthesia, the urethra was catheterized. An incision was made at the anatomic location of the anus, the rectovaginal fistula was isolated through deep dissection, and a Penrose drain was placed around it for caudal retraction. Transvaginal catheter placement through the fistula and into the rectum assisted with anatomic location. Once the urogenital and gastrointestinal tracts were clearly identified, the fistula was transected as close to the vaginal cavity as possible. The vaginal defect was sutured, and the fistula tract was mobilized 90° and sutured to the skin, creating the anal canal. Postoperative complications included constipation and cystitis. The gilt passed feces 5 d after surgery and was discharged on Day 11 of hospitalization. Normal urination and defecation were observed at the time, and fecal incontinence was resolved. Six months after surgical intervention, the gilt remained continent and no complications were reported. Key clinical message: Anoplasty and rectovaginal fistula repair were completed successfully in a gilt. Preservation of the fistula and its use during anal reconstruction may provide an internal anal sphincter and may be associated with improved continence.

Anoplastie et réparation de la fistule recto-vaginale chez une cochette avec atrésie anale : rapport de cas. Une femelle cochon vietnamien de 2 ans a été référée au Large Animal Teaching Hospital du Ontario Veterinary College pour une anoplastie et réparation d'une fistule recto-vaginale. La présence d'une atrésie anale et d'une fistule recto-vaginale avait déjà été diagnostiquée. Une radiographie de contraste a été utilisée pour confirmer le diagnostic et déterminer la position de la fistule et du rectum terminal. Sous anesthésie générale, l'urètre a été cathétérisé. Une incision a été faite à l'emplacement anatomique de l'anus, la fistule recto-vaginale a été isolée par dissection profonde et un drain de Penrose a été placé autour d'elle pour la rétraction caudale. Le placement d'un cathéter transvaginal à travers la fistule et dans le rectum a aidé avec la localisation anatomique. Une fois les voies urogénitale et gastro-intestinale clairement identifiées, la fistule a été sectionnée aussi près que possible de la cavité vaginale. Le défaut vaginal a été suturé et le trajet de la fistule a été mobilisé à 90° et suturé à la peau, créant le canal anal. Les complications postopératoires incluaient la constipation et la cystite. La cochette a expulsé des matières fécales 5 jours après la chirurgie et a obtenu son congé le 11e jour d'hospitalisation. Une miction et une défécation normales ont été observées à ce moment-là, et l'incontinence fécale a été résolue. Six mois après l'intervention chirurgicale, la cochette présentait encore de la continence urinaire et aucune complication n'a été signalée.Message clinique clé :L'anoplastie et la réparation de la fistule recto-vaginale ont été réalisées avec succès chez une cochette. La préservation de la fistule et son utilisation lors de la reconstruction anale peuvent fournir un sphincter anal interne et peuvent être associées à une meilleure continence.(Traduit par Dr Serge Messier).

Corrigendum: Extracorporeal Shock Wave Therapy Enhances the In Vitro Metabolic Activity and Differentiation of Equine Umbilical Cord Blood Mesenchymal Stromal Cells.

[This corrects the article DOI: 10.3389/fvets.2020.554306.].

Fragment size is associated with post-operative complications following elective arthroscopy of the tibiotarsal joint of horses.

The objective of this retrospective study was to determine the occurrence of joint-related complications after elective arthroscopy of the tibiotarsal joint (TTJ) in 329 horses, and the association with specific clinical parameters. Data were collected from medical records of horses undergoing elective tibiotarsal joint arthroscopy for fragment removal. Exact conditional univariate regression was used to determine significant risk factors for joint-related post-operative complications. Of 485 joints, 2 (0.4%) developed surgical site infection, 4 (0.8%) developed septic arthritis, 1 (0.2%) developed synovial fistula. There was a significantly increased odds of having septic arthritis as height and length of the distal intermediate ridge of the tibia (DIRT) lesion increased. The median height and length of the DIRT fragments in affected cases was 13.5 mm and 18.0 mm, respectively. For each unit (1 mm) increase in height, there was a 42% increase in the risk of septic arthritis occurrence (P = 0.0042), and a 15% increase for each unit increase in length (P = 0.035). Horses were significantly less likely to develop septic arthritis when suture smaller than USP 0 was used. Horses with larger osteochondritis dissecans lesions of the DIRT region have an increased risk of developing septic arthritis following fragment removal.

La taille des fragments est associée à des complications postopératoires après arthroscopie élective de l'articulation tibiotarsienne des chevaux. L'objectif de cette étude rétrospective était de déterminer la fréquence de complications articulaires après arthroscopie élective de l'articulation tibiotarsienne (TTJ) chez 329 chevaux, et l'association avec des paramètres cliniques spécifiques. Les données ont été recueillies à partir des dossiers médicaux de chevaux subissant une arthroscopie élective de l'articulation tibiotarsienne pour l'élimination de fragments. Une régression univariée conditionnelle exacte a été utilisée pour déterminer les facteurs de risque significatifs de complications postopératoires liées aux articulations.Sur 485 articulations, deux (0,4 %) ont développé une infection du site opératoire, quatre (0,8 %) une arthrite septique, et une (0,2 %) une fistule synoviale. Il y avait une probabilité significativement accrue d'avoir une arthrite septique à mesure que la hauteur et la longueur de la lésion de la crête intermédiaire distale du tibia (DIRT) augmentaient. La hauteur et la longueur médianes des fragments DIRT dans les cas affectés étaient respectivement de 13,5 mm et de 18,0 mm. Pour chaque unité (1 mm) d'augmentation de hauteur, il y avait une augmentation de 42 % du risque de survenue d'arthrite septique (P = 0,0042); et une augmentation de 15 % pour chaque augmentation unitaire de longueur (P = 0,035). Les chevaux étaient significativement moins susceptibles de développer une arthrite septique lorsqu'une suture plus petite que USP 0 était utilisée.Les chevaux présentant des lésions d'ostéochondrite disséquante plus importantes de la région DIRT ont un risque accru de développer une arthrite septique après le retrait des fragments.(Traduit par Dr Serge Messier).

Development and Validation of a Three-Dimensional Printed Training Model to Teach Ultrasound-Guided Injections of the Cervical Articular Process Joints in Horses.

Intra-articular injections are routinely performed to alleviate pain and inflammation associated with osteoarthritis in horses. Intra-articular injections require accurate needle placement to optimize clinical outcomes and minimize complications. This study's objectives were to develop and validate a three-dimensional (3D) printed model of an equine cervical articular process joint to teach ultrasound-guided injections. Five identical models of an equine cervical articular process joint were 3D printed and embedded in 10% ballistic gelatin. Experts' and novices' ability to successfully insert a needle into the joint space of the model using ultrasound guidance was assessed and graded using an objective structured clinical examination (OSCE). Scores from experts and novices were compared to evaluate the construct validity of the model. Participants also answered a survey assessing the face and content validity of the model. Experts required less time (22.51 seconds) for correct needle placement into the model joint space than novices (35.96 seconds); however, this difference was not significant (p = .53). Experts' median total OSCE score (14) was significantly higher (p = .03) than novices' (12), supporting the model's construct validity. Participants agreed on the face and content validity of the model by grading all survey questions greater than 7 on a 10-point Likert-type scale. In summary, we successfully developed a 3D printed model of an equine cervical articular process joint, partially demonstrated the construct validity of the model, and proved the face and content validity of this new training tool.

Extracorporeal Shock Wave Therapy Enhances the In Vitro Metabolic Activity and Differentiation of Equine Umbilical Cord Blood Mesenchymal Stromal Cells.

Extracorporeal shock wave therapy (ESWT) has been shown to induce different biological effects on a variety of cells, including regulation and stimulation of their function and metabolism. ESWT can promote different biological responses such as proliferation, migration, and regenerations of cells. Recent studies have shown that mesenchymal stromal cells (MSCs) secrete factors that enhance the regeneration of tissues, stimulate proliferation and differentiation of cells, and decrease inflammatory and immune reactions. Clinically, the combination of these two therapies has been used as a treatment for tendon and ligament lesions in horses; however, there is no scientific evidence supporting this combination of therapies in vivo. Therefore, the objectives of the study were to evaluate the effects of ESWT on equine umbilical cord blood mesenchymal stromal cells (CB-MSCs) proliferative, metabolic, migrative, differentiation, and immunomodulatory properties in vitro. Three equine CB-MSC cultures from independent donors were treated using an electrohydraulic shock wave generator attached to a water bath. All experiments were performed as triplicates. Proliferation, viability, migration and immunomodulatory properties of the cells were evaluated. Equine CB-MSCs were induced to evaluate their trilineage differentiation potential. ESWT treated cells had increased metabolic activity, showed positive adipogenic, osteogenic, and chondrogenic differentiation, and showed higher potential for differentiation toward the adipogenic and osteogenic cell fates. ESWT treated cells showed similar immunomodulatory properties to none-ESWT treated cells. Equine CB-MSCs are responsive to ESWT treatment and showed increased metabolic, adipogenic and osteogenic activity, but unaltered immunosuppressive properties. In vivo studies are warranted to determine if synergistic effects occur in the treatment of musculoskeletal injuries if ESWT and equine CB-MSC therapies are combined.

Case-Control Comparison of Cervical Spine Radiographs From Horses With a Clinical Diagnosis of Cervical Facet Disease With Normal Horses.

The accuracy of using radiographs to diagnose cervical facet osteoarthritis (CFA) in horses is undetermined. Further investigation is required to determine the clinical significance of radiographic evidence of CFA, the prevalence of radiographic changes in horses without clinical signs, and the long-term efficacy of intra-articular CFA treatment. The objectives of this study is to compare degenerative changes of the cervical facet joints of the cervical vertebrae on radiographs of horses with clinical signs of CFA with healthy cohort-matched horses, to compare clinical findings between groups, and to obtain follow-up information on the long-term outcome in treated horses. This is a retrospective case-control cohort-matched comparison study of horses treated for cervical facet disease versus horses with no clinical signs of cervical facet disease. Horses diagnosed with CFA and treated with intra-articular injection of corticosteroids were included. Follow-up information on recovery from treatment was obtained via telephone survey of owners/trainers. Healthy horses with no clinical signs of CFA were matched to treated horses by breed, sex, age, and sport as the control group. Two blinded radiologists reviewed cervical spine radiographs for each horse and recorded CFA score and intravertebral/intervertebral measurements. Clinical and radiographic parameters were compared between treatment and control groups. There was a significant difference in CFA grades for C5-6 and C6-7 between horses with presence of clinical signs and healthy horses. However, interobserver agreement between radiologists for grading CFA was moderate and only 56% of values were identical for both observers. Atrophy of the neck was present on clinical examination in most cases in the treatment group. Dressage horses were overrepresented. Overall, 64% of horses returned to their previous level of performance after treatment. Clinical examination data collected for the treatment group were retrospective and were obtained by different clinicians. Eight owners/trainers were not able to be reached for the survey. There was a significant difference in CFA grades for C5-6 and C6-7 between horses with presence of clinical signs and healthy horses. Despite these statistical differences, the clinical diagnosis of CFA based on radiographic grading alone is questionable because of the lack of agreement between the radiologists. To strengthen the diagnosis, clinical signs of facet disease, in particular atrophy of the neck muscles, need to be present to make this diagnosis. Intra-articular corticosteroid injection was effective at allowing most treated horses to return to athletic use..

Postinjury performance for differing humeral stress fracture locations in the racing thoroughbred.

OBJECTIVE: To assess the influence of humeral stress fracture location on the time to return to racing and postinjury performance of thoroughbred racehorses. STUDY DESIGN: Retrospective study (1992-2015). SAMPLE POPULATION: Thoroughbred racehorses (n = 131) that presented for lameness with the sole diagnosis of humeral stress fractures in the lame limb, as determined by scintigraphy or radiology. METHODS: Sex, fracture site, age, starts, earnings, and average earnings per race were examined for differences in pre-stress and post-stress fracture diagnosis for the entire population as well as individual stress fracture locations (general linear model, χ2 tests). Pre-stress and post-stress fracture performance for the three stress fracture locations were assessed: (1) earnings pre-stress and post-stress fracture (Kruskal-Wallis one-way analysis of variance), (2) average earnings per start prefracture, and (3) average earnings per start postfracture (Wilcoxon signed-rank tests). RESULTS: Stress fracture locations were caudodistal (n = 36), craniodistal (n = 43), and caudoproximal (n = 52). One hundred ten of 131 horses raced postfracture, and 54 of 131 horses raced prefracture. Age at injury was 43.61 months caudodistal, 33.48 months caudoproximal, and 36.65 months craniodistal. Horses returned to race at a median of 244 days (range, 218-272). Postfracture earnings per start were greater for caudodistal vs caudoproximal (P = .04). CONCLUSION: There were no differences in prefracture earnings or fracture site and sex or limb affected. Return-to-race time varied by location but not significantly. Differences in earnings preinjury and postinjury were not significant. Horses with a stress fracture at the caudodistal location earned significantly more compared with horses with a stress fracture at the caudoproximal location after they returned to race. CLINICAL SIGNIFICANCE: Thoroughbred racehorses have a good prognosis for return to racing regardless of fracture location.

Various 3D printed materials mimic bone ultrasonographically: 3D printed models of the equine cervical articular process joints as a simulator for ultrasound guided intra-articular injections.

INTRODUCTION: In the equine racehorse industry, reduced athletic performance due to joint injury and lameness has been extensively reviewed. Intra-articular injections of glucocorticoids are routinely used to relieve pain and inflammation associated with osteoarthritis. Intra-articular injections of pharmaceutical agents require practice for precise needle placement and to minimize complications. Training on simulators or models is a viable alternative for developing these technical skills. The purpose of this study was to compare the qualitative ultrasonographic characteristics of three-dimensional (3D) printed models of equine cervical articular process joints to that of a dissected equine cervical spine (gold standard). METHODS: A randomized complete block design study was conducted in which a total of thirteen cervical articular process joint models were printed using several materials, printers, and printing technologies. Ultrasound video clips with the models immersed in water were recorded. Two board certified veterinary radiologists and three veterinary radiology residents reviewed the videos and responded to a survey assessing and comparing the ultrasonographic characteristics of the 3D printed models to those of the gold standard. RESULTS: Six 3D printed models had ultrasonographic characteristics similar to the gold standard. These six models were (material, printer, printing technology): nylon PA 12, EOS Formiga P100, selective laser sintering (P = 0.99); Onyx nylon with chopped carbon fiber, Markforged Onyx Two, fused deposition modeling (P = 0.48); polycarbonate, Ultimaker 3, fused deposition modeling (P = 0.28); gypsum, ProJet CJP 660 Pro, ColorJet Printing (P = 0.28); polylactic acid, Prusa I3, fused deposition modeling (P = 0.23); and high temperature V1 resin, Form 2, stereolithography (P = 0.22). CONCLUSION: When assessed in water, it is possible to replicate the qualitative ultrasonographic characteristics of bone using three dimensional printed models made by combining different materials, printing technologies, and printers. However, not all models share similar qualitative ultrasonographic characteristics with bone. We suggest that the aforementioned six models be used as proxy for simulating bones or joints for use with ultrasound. In order to replicate the resistance and acoustic window provided by soft tissues, further work testing the ability of these models to withstand embedding in material such as ballistic gelatin is required.

Incarceration of the small intestine through a rent in the ileocecal fold in a horse.

Small intestinal incarceration in a rent within the ileocecal fold is an uncommon finding in horses. This report describes the history, clinical signs, and surgical findings in a horse with small intestinal strangulation due to a rent at the ileocecal fold.

Incarcération du petit intestin par une déchirure dans le pli iléo-caecal chez un cheval. L'incarcération du petit intestin dans une déchirure du pli iléo-caecal est une constatation rare chez les chevaux. Ce rapport décrit l'anamnèse, les signes cliniques et les constatations chirurgicales d'un cheval atteint d'une strangulation du petit intestin en raison d'une déchirure dans le pli iléo-caecal.(Traduit par Isabelle Vallières).

Clinical indications, complications, and long-term outcome of esophageal surgeries in 27 horses.

The main objective of this retrospective study was to describe clinical findings, management, and short- and long-term outcome in 27 horses that underwent various surgical techniques for esophageal disease. Surgical techniques (sometimes concurrently) performed were: esophagostomy (n = 14), esophagotomy with primary closure (n = 6), esophagomyotomy (n = 3), and esophagoplasty (n = 2). Esophageal perforation in 5 horses was treated by ventral drainage; 3 horses had the esophageal defect sutured (n = 3). Feeding tubes were placed in 15 horses. Postoperative complications occurred in 52% (14/27) with a median of 3 complications/horse (range: 1 to 7). Significantly more complications occurred in horses with a perforated esophagus. Eighteen horses (18/27; 67%) were discharged. Most horses (8/9; 89%) with a lesion located in the proximal esophagus were discharged. Horses with a higher number of postoperative complications, particularly postoperative infection, were more likely to be euthanized. One year after surgery, 41% of the horses were alive and free of complications.

Indications cliniques, complications et résultat à long terme de chirurgies œsophagiennes chez 27 chevaux. L'objectif principal de cette étude rétrospective a été de décrire les résultats cliniques, la gestion et les résultats à court et à long terme chez 27 chevaux qui ont subi diverses techniques de chirurgie pour le traitement de la maladie œsophagienne. Les techniques chirurgicales réalisées (parfois de manière concomitante) étaient : l'œsophagostomie (n = 14), l'œsophagotomie avec fermeture primaire (n = 6), l'œsophagomyotomie (n = 3) et l'œsophagoplastie (n = 2). La perforation œsophagienne chez 5 chevaux a été traitée par drainage ventral; 3 chevaux ont subi une suture du défaut œsophagien (n = 3). Des sondes d'alimentation ont été placées chez 15 chevaux. Les complications postopératoires se sont produites chez 52 % des chevaux (14/27) avec une médiane de 3 complications/cheval (fourchette : 1 à 7). Un nombre significativement supérieur de complications se sont produits chez les chevaux ayant une perforation de l'œsophage. Dix-huit chevaux (18/27; 67 %) ont reçu leur congé. La plupart des chevaux (8/9; 89 %) ayant une lésion situé dans l'œsophage proximal ont reçu leur congé. Il était plus probable que les chevaux avec un nombre supérieur de complications postopératoires, particulièrement une infection postopératoire, soient euthanasiés. Un an après la chirurgie, 41 % des chevaux étaient vivants et libres de complications.(Traduit par Isabelle Vallières).

Response to Intravenous Allogeneic Equine Cord Blood-Derived Mesenchymal Stromal Cells Administered from Chilled or Frozen State in Serum and Protein-Free Media.

Equine mesenchymal stromal cells (MSC) are commonly transported, chilled or frozen, to veterinary clinics. These MSC must remain viable and minimally affected by culture, transport, or injection processes. The safety of two carrier solutions developed for optimal viability and excipient use were evaluated in ponies, with and without allogeneic cord blood-derived (CB) MSC. We hypothesized that neither the carrier solutions nor CB-MSC would elicit measurable changes in clinical, hematological, or biochemical parameters. In nine ponies (study 1), a bolus of HypoThermosol(®) FRS (HTS-FRS), CryoStor(®) CS10 (CS10), or saline was injected IV (n = 3/treatment). Study 2, following a 1-week washout period, 5 × 10(7) pooled allogeneic CB-MSCs were administered IV in HTS-FRS following 24 h simulated chilled transport. Study 3, following another 1-week washout period 5 × 10(7) pooled allogeneic CB-MSCs were administered IV in CS10 immediately after thawing. Nine ponies received CB-MSCs in study 2 and 3, and three ponies received the cell carrier media without cells. CB-MSCs were pooled in equal numbers from five unrelated donors. In all studies, ponies were monitored with physical examination, and blood collection for 7 days following injection. CD4 and CD8 lymphocyte populations were also evaluated in each blood sample. In all three studies, physical exam, complete blood cell count, serum biochemistry, and coagulation panel did not deviate from established normal ranges. Proportions of CD4(+) and CD8(+) lymphocytes increased at 168 h postinjection in CB-MSC treatment groups regardless of the carrier solution. Decreases in CD4(+/)CD8(+) double positive populations were observed at 24 and 72 h in CB-MSC-treated animals. There was no difference in viability between CB-MSCs suspended in HTS-FRS and CS10. HTS-FRS and CS10 used for low volume excipient injection of MSC suspensions were not associated with short-term adverse reactions. HTS-FRS and CS10 both adequately maintain CB-MSC viability following hypothermic or frozen simulated transport, respectively. CB-MSCs do not elicit clinical abnormalities, but allogeneic stimulation of CD4(+) and CD8(+) lymphocyte populations may occur. Future studies should include in vitro or in vivo evaluation of cell-mediated or adaptive immunity to autologous, identical allogeneic, or MSC originating from additional unrelated individuals in order to better characterize this response.

Aspiration, but not injection, decreases cultured equine mesenchymal stromal cell viability.

BACKGROUND: Recently, equine multipotent mesenchymal stromal cells (MSC) have received significant attention as therapy for various conditions due to their proposed regenerative and immune-modulating capacity. MSC are commonly administered to the patient through a hypodermic needle. Currently, little information is available on the effect of such injection has on equine MSC immediate and delayed viability. We hypothesize that viability of equine MSC is not correlated with needle diameter during aspiration and injection. RESULTS: Using a 3 mL syringe, manual injection of equine cord blood (CB) or bone marrow-derived (BM) MSC with no needle and needles ranging in size from 18 to 30 Ga did not affect immediate MSC viability. Similarly, 24 h post-injection, MSC delayed viability was not different between any of the tested needles as determined by a resazurin-based proliferation assay. Using a 3 mL syringe, aspiration of MSC through 20, 25, and 30 Ga needles resulted in significant decreases in immediate viability with no change in delayed viability when compared to aspiration without a needle. BM- and CB-MSC were observed to be of similar size with a diameter ± SD of 19.8 ± 2.7 and 20.4 ± 2.2 µm, respectively. In comparison, the smallest needles, (30 Ga) have an internal diameter of 160 µm. CONCLUSIONS: Following injection, needle diameter did not affect immediate or delayed viability of equine MSC. Following aspiration through needles sizes 20 Ga and smaller, immediate viability, but not delayed viability, decreased. As a result, an 18 Ga or larger needle should be utilized for aspiration of cell suspensions. In contrast, needle selection for MSC injection should be based on clinical preference and experience rather than concerns over decreasing MSC viability.

Comparison of laparoscopic versus conventional open cryptorchidectomies on intraoperative and postoperative complications and duration of surgery, anesthesia, and hospital stay in horses.

Objective-To compare surgical preparation time, surgery and anesthesia times, hospitalization duration, and intra- and postoperative complications between laparoscopic and conventional open cryptorchidectomy in horses. Design-Retrospective cohort study. Animals-60 horses that underwent cryptorchidectomy. Procedures-Medical records were reviewed to identify horses that had undergone cryptorchidectomy from 1991 to 2012. Thirty horses that underwent laparoscopic cryptorchidectomy (case horses) were matched with 30 control horses that had undergone open cryptorchidectomy (ie, inguinal and parainguinal surgical approaches). Horses were matched according to history of previous surgery, testicle location, and type of closure following removal of an undescended unilateral testicle. Duration of surgery, surgical preparation and anesthesia times, hospitalization duration, and number of intra- and postoperative complications were compared between horses that underwent laparoscopic cryptorchidectomy versus open cryptorchidectomy. Comparisons were also made between horses in terms of whether there was a history of previous failed cryptorchidectomy or unknown location of testicle prior to surgery. Results-Horses that underwent laparoscopic cryptorchidectomy had significantly longer surgery and anesthesia times overall, compared with horses that underwent open cryptorchidectomy. No difference in surgery time was found between case and control horses that had a previous surgical attempt to remove an undescended testicle or in which the testicle location was unknown prior to surgery. Overall, horses undergoing laparoscopy had a nonsignificant increase in intraoperative complications, compared with control horses, and had significantly more postoperative complications. Conclusions and Clinical Relevance-Horses undergoing laparoscopic cryptorchidectomy had increased surgical preparation time, increased surgery and anesthesia times, and more postoperative complications, compared with horses undergoing open cryptorchictomy. Laparoscopy may be advantageous for a second attempt at cryptorchidectomy or if the testicle location is unknown prior to surgery.

Post-thaw non-cultured and post-thaw cultured equine cord blood mesenchymal stromal cells equally suppress lymphocyte proliferation in vitro.

Multipotent mesenchymal stromal cells (MSC) are receiving increased attention for their non-progenitor immunomodulatory potential. Cryopreservation is commonly used for long-term storage of MSC. Post-thaw MSC proliferation is associated with a lag-phase in vitro. How this lag-phase affect MSC immunomodulatory properties is unknown. We hypothesized that in vitro there is no difference in lymphocyte suppression potential between quick-thawed cryopreserved equine cord blood (CB) MSC immediately included in mixed lymphocyte reaction (MLR) and same MSC allowed post-thaw culture time prior to inclusion in MLR. Cryopreserved CB-MSC from five unrelated foals were compared using two-way MLR. For each of the five unrelated MSC cultures, paired MLR assays of MSC allowed five days of post-thaw culture and MSC included in MLR assay immediately post-thawing were evaluated. We report no difference in the suppression of lymphocyte proliferation by CB-MSC that had undergone post-thaw culture and MSC not cultured post-thaw (p<0.0001). Also, there was no inter-donor variability between the lymphocyte suppressive properties of MSC harvested from the five different donors (p = 0.13). These findings suggest that cryopreserved CB-MSC may have clinical utility immediately upon thawing. One implication hereof is the possibility of using cryopreserved CB-MSC at third party locations without the need for cell culture equipment or competencies.

Evaluation of ultrasmall superparamagnetic iron oxide contrast agent labeling of equine cord blood and bone marrow mesenchymal stromal cells.

OBJECTIVE: To evaluate the efficacy and effects of labeling equine umbilical cord blood (UCB)- and bone marrow (BM)-derived multipotent mesenchymal stromal cells (MSCs) with an ultrasmall superparamagnetic iron oxide (SPIO) contrast agent and the detection of labeled MSCs by use of MRI. SAMPLE: UCB MSCs from placental tissues of 5 foals and BM MSCs from 5 horses. PROCEDURES: UCB and BM MSC cultures were seeded in duplicate (5,000 cells/cm(2)). One duplicate was incubated with SPIO (50 µg/mL); the other was processed identically, but without SPIO. Mesenchymal stromal cells were expanded in triplicates for 5 passages and assessed for viability and proliferative capacity, labeling efficacy, and labeled cell proportion. For MRI detection, 5 × 10(6) labeled BM MSCs from passage 1 or 2 were injected into a collagenase-induced superficial digital flexor tendon defect of an equine cadaveric forelimb from 2 horses. RESULTS: For passages 1, 2, and 3, labeling efficacy and cell proportion for UCB MSCs (99.6% [range, 98.8% to 99.9%], 16.6% [range, 6.5% to 36.1%], and 1.0% [range, 0.4% to 2.8%], respectively) were significantly higher than for BM MSCs (99.2% [range, 97.8% to 99.7%], 4.5% [range, 1.6% to 11.8%], and 0.2% [range, 0.1% to 0.6%], respectively). Labeling was not detectable after passage 3. Viability of MSCs was not affected, but cell doubling time increased in labeled MSCs, compared with that of unlabeled MSCs. On MRI 3-D T2*-weighted fast gradient echo sequences, decreased signal intensity was observed for BM passage 1 MSCs. CONCLUSIONS AND CLINICAL RELEVANCE: Equine UCB and BM MSCs were labeled with SPIO at high efficiencies.

Evaluation of a broad range real-time polymerase chain reaction (RT-PCR) assay for the diagnosis of septic synovitis in horses.

Septic synovitis is a potentially debilitating and life-threatening disorder in horses. We hypothesized that a universal bacterial real-time PCR (RT-PCR) assay would have improved sensitivity and decreased turn-around time for detection of bacteria in synovial fluid (SF) samples. Forty-eight SF samples were collected from 36 horses that presented to two referral institutions with suspected septic synovitis. Universal RT-PCR, bacterial culture and SF analysis were performed on all samples, and an interpretation on the sample being septic or not was derived by three board certified specialists from the history, clinical assessment and SF characteristics. RT-PCR results were compared to a composite standard comprised of positive culture and interpretation by all three specialists of samples as "septic". For 41 of 48 samples (85%), culture and RT-PCR results were concordant. Compared to the composite standard, 83% of samples were correctly classified by RT-PCR (turn-around time of approximately 4 hours). Relative sensitivity and specificity of RT-PCR were 87% and 72% respectively, and 56% and 86% for culture. Hence, universal RT-PCR was a rapid and highly sensitive test, which may accelerate diagnosis and improve outcome for horses with septic synovitis.

La synovite septique est une condition potentiellement débilitante et mortelle chez les chevaux. Nous avons émis l'hypothèse qu'une épreuve universelle d'amplification en chaîne par la polymérase en temps réel (RT-PCR) pourrait avoir une sensibilité augmentée et une diminution du délai d'obtention des résultats pour la détection de bactérie dans des échantillons de liquide synovial (SF). Quarante-huit échantillons de SF ont été prélevés à partir de 36 chevaux présentés à deux centres de référence avec une synovite septique suspectée. L'épreuve RT-PCR universelle, la culture bactérienne et l'analyse du SF ont été effectuées sur tous les échantillons et une interprétation à savoir si l'échantillon était septique ou non était obtenue de trois spécialistes certifiés à partir de l'histoire du cas, de l'évaluation clinique et des caractéristiques du SF. Les résultats du RT-PCR ont été comparés à un composite standard consistant en une culture et une interprétation positives par les trois spécialistes d'échantillons comme étant «septique¼. Pour 41 des 48 échantillons (85 %), les résultats de la culture et du RT-PCR concordaient. Comparativement au composite standard, 83 % des échantillons ont été classés correctement par le RT-PCR (délai d'obtention des résultats approximatif de 4 heures). La sensibilité et la spécificité relatives du RT-PCR étaient de 87 % et 72 %, respectivement, 56 % et 86 % pour la culture. Ainsi, l'épreuve RT-PCR universelle était un test rapide et hautement sensible, ce qui pourrait accélérer le diagnostic et améliorer le sort des chevaux avec une synovite septique.(Traduit par Docteur Serge Messier).

Effect of unfocused extracorporeal shock wave therapy on growth factor gene expression in wounds and intact skin of horses.

OBJECTIVE: To compare the effect of extracorporeal shock wave therapy (ESWT) on expression of fibroblast growth factor-7 (FGF-7), transforming growth factor-ß1 (TGF-ß1), insulin-like growth factor-1 (IGF-1), platelet-derived growth factor-A (PDGF), and vascular endothelial growth factor-A (VEGF) in skin with surgically created skin wounds and intact skin in horses. ANIMALS: 14 healthy horses. PROCEDURE: 8 horses were treated with ESWT at 6 locations along the neck at 36, 24, 12, 6, 2, or 1 hour prior to collection of full-thickness biopsy specimens from each location; a control specimen was collected from a sham-treated location. In 6 horses, 5 full-thickness wounds were created in each forelimb. Wounds in 1 forelimb/horse received ESWT immediately after creation and subsequently on days 7, 14, and 21; wounds in the contralateral forelimb remained untreated. Biopsy specimens were collected from 1 wound on each forelimb on days 7, 14, 21, 28, and 35. Expression levels of FGF-7, TGF-ß1, IGF-1, PDGF, and VEGF were assessed in tissue samples from the horses' necks and forelimbs. RESULTS: In surgically created wounds, ESWT treatment was associated with reduced TGF-ß1 expression, compared with expression in control wounds, during the entire study period. At 28 days following wound creation, IGF-1 expression was significantly increased for treated and untreated wounds, compared with findings on days 7, 14, 21, and 35. There was no significant effect of treatment on FGF-7, TGF-ß1, IGF-1, PDGF, or VEGF expression in intact skin. CONCLUSIONS AND CLINICAL RELEVANCE: Intervention with ESWT to suppress TGF-ß1 may decrease granulation tissue production, resulting in improved wound healing on the distal portion of horses' limbs.

Anesthetic management of a white rhinoceros (Ceratotherium simum) undergoing an emergency exploratory celiotomy for colic.

OBSERVATIONS: A 26-year-old male white rhinoceros (Ceratotherium simum), weighing approximately 2000 kg was anesthetized for an exploratory celiotomy. Sedation was achieved with intramuscular butorphanol (0.04 mg kg(-1)) and detomidine (0.025 mg kg(-1)) and induction of anesthesia with intravenous glyceryl guaiacolate (50 g) and three intravenous boluses of ketamine (200 mg, each); the trachea was then intubated and anesthesia maintained with isoflurane in oxygen using a circle breathing system. Positioning in dorsal recumbency for the surgery and later in sternal recumbency for the recovery represented challenges that added to the prolonged anesthesia time and surgical approach to partially correct an impaction. The rhinoceros recovered uneventfully after 10.4 hours of recumbency. CONCLUSIONS: Anesthetic management for an exploratory celiotomy with a midline approach is possible in rhinoceroses, although planning and extensive staff support is necessary to adequately position the patient.