Comparison of Two Bandage Splint Constructs in an Ex Vivo Equine Metacarpal Fracture Model.

OBJECTIVES: The aim of this study was to compare the deflection distance, deflection angle and pre-loading sub-bandage pressure of a transverse, mid-metacarpal fracture in an equine cadaver limb when loaded in bending while stabilized with either a Robert Jones Bandage (RJB) or a single-stack bandage (SS), each containing two orthogonal splints. STUDY DESIGN: In an ex vivo experimental study, forelimb pairs from eight horses were collected, and one forelimb from each pair was assigned to either the SS or RJB groups. A transverse osteotomy was performed at the midpoint of the metacarpus. After bandaging, the limbs were loaded in bending. Pre-loading sub-bandage pressure, pre- and post-loading radiographs and post-loading deflection distance measurements were taken. Dorsopalmar radiographs were used to measure the loaded deflection angle. RESULTS: There was no significant difference between RJB and SS constructs in change in deflection angle (10.7 ± 3.0 degrees vs. 9.8 ± 2.6 degrees; p = 0.5) or deflection distance (13.1 ± 2.6 cm vs. 11.4 ± 3.1 cm; p = 0.2). Sub-bandage pressures were significantly greater for the SS than the RJB both dorsally and laterally. CONCLUSION: The SS splint construct resists bending forces similarly to the RJB splint construct in an ex vivo transverse, metacarpal fracture model. The SS splint construct may be a useful alternative to the RJB splint construct in field situations for metacarpal fracture stabilization.

Therapeutics prior to mesenchymal stromal cell therapy improves outcome in equine orthopedic injuries.

OBJECTIVE: Mesenchymal stromal (stem) cells (MSCs) have been studied to treat many common orthopedic injuries in horses. However, there is limited information available on when and how to use this treatment effectively. The aim of this retrospective study is to report case features, treatment protocols, and clinical outcomes in horses treated with MSCs. ANIMALS: 65 horses presenting with tendinous, ligamentous, and articular injuries, and treated with MSCs prepared by a single laboratory between 2016 and 2019. Outcome information was available for 26 horses. PROCEDURES: Signalment, clinical signs, diagnostic methods, treatment protocol features (prior and concurrent therapies, cell origin, dose, application site and number), and effective outcomes were analyzed. The analysis was focused on comparing the effect of different MSC treatment protocols (eg, autologous vs allogeneic) on outcome rather than the effectiveness of MSC treatment. RESULTS: MSC treatment resulted in 59.1% (clinical lameness) to 76.9% (imaging structure) improvement in horses with diverse ages, breeds, sex, and lesions. The use of other therapeutic methods before MSC application (eg, anti-inflammatories, shockwave, laser, icing, resting, bandage and stack wrap, intra-articular injections, and/or surgical debridement) was shown to be statistically more effective compared to MSCs used as the primary therapeutic procedure (P < .05). Autologous versus allogeneic treatment outcomes were not significantly different. CLINICAL RELEVANCE: A prospective MSC treatment study with standardization and controls to evaluate the different features of MSC treatment protocols is needed. The various case presentations and treatment protocols evaluated can be used to inform practitioners who are currently using MSCs in clinical practice.

Healing time of experimentally induced distal limb wounds in horses is not reduced by local injection of equine-origin liquid amnion allograft.

OBJECTIVE: To assess the efficacy of an equine-origin liquid amnion allograft (ELAA) derived from both amniotic fluid and amniotic membrane on the healing time of experimentally induced distal limb wounds in horses. ANIMALS: 8 adult horses. PROCEDURES: On day 0, horses were anesthetized and a 2.5 X 2.5-cm, full-thickness skin wound was created on the dorsal aspect of each metacarpus and bandaged. On day 9, wound margins were injected with ELAA (treatment) or 0.9% NaCl (control). Bandages were changed at specific intervals through day 91 and, on each occasion, wounds were photographed to allow calculation of wound area. Exuberant granulation tissue was resected, if present. Wounds were deemed healed when completely epithelialized. Mean wound area was compared between groups throughout the study period. RESULTS: Only 1 wound (control) remained unhealed at day 91. No difference was found between the treatment and control groups in either wound area over time (P = 1.0) or time for wounds to reduce in size by 95% (P = .2) Exuberant granulation tissue required resection twice (1 control wound and 1 treatment wound). CLINICAL RELEVANCE: In this model, a single treatment with ELAA administered locally by SC injection did not accelerate distal limb wound healing in horses. However, it is possible that naturally occurring, chronic, or nonhealing wounds would respond differently.

Interleukin-6 and lactate dehydrogenase expression in a novel ex vivo rocking model of equine corneal epithelial wound healing.

PURPOSE: To establish a physiologically relevant ex vivo model of equine corneal epithelial wound healing. METHODS: Fourteen equine corneas were randomly assigned to one of two groups: wounded (n = 8) or unwounded (n = 6) controls. In the wounded group, the axial corneal epithelium was removed by applying a 6 mm filter paper disk soaked in 1N-NaOH for 60 s. Corneas were subsequently cultured using an air-liquid interface model. Evaluation of corneal healing was performed daily, and culture medium was collected. Corneas were randomly assigned to undergo processing via histopathology and RNAscope in situ hybridization for interleukin-6 (IL-6) and alpha-smooth muscle actin (αSMA) expression at T24, T48, and T72 h after wounding. Media of the cultured corneas were evaluated for the presence of lactate dehydrogenase (LDH) by a colorimetric assay. RESULTS: The ulcerated area of the wounded corneas decreased over time and all corneas healed within 72 h. Histologically, normal corneal architecture was observed including healthy epithelium (in areas other than the ulcerated ones), minimal stromal edema, intact endothelium, and Descemet's membrane. IL-6 expression was increased in wounded corneas compared with unwounded controls. LDH expression was elevated for both wounded and unwounded corneas at T24 but decreased substantially and was not detected at T48 in media from wounded and unwounded corneas, respectively. No αSMA expression was detected from either wounded or unwounded corneas. CONCLUSIONS: The equine air-liquid interface, ex vivo, corneal epithelial wound healing model is effective and physiologically relevant. This model can be used in future studies evaluating various corneal therapies.

Drivers of exit and outcomes for Thoroughbred racehorses participating in the 2017-2018 Australian racing season.

The destinations of Thoroughbred (TB) racehorses exiting the racing industry is a high-profile issue with ethical and welfare implications of interest to both animal welfare groups and racing regulators. This cross-sectional study investigated the reasons that TBs temporarily or permanently exited racing and training in Australia in the 2017-2018 racing season and the outcomes for these horses post-racing. An online questionnaire was sent to the last registered trainers of a representative sample of 2,509 'inactive' TBs. Inactive horses were defined as those horses that were recorded as 'active' but had not trialled or raced in the last 6 months of the racing season or had an inactive status recorded in the Racing Australia database. Of the 1,750 responses received, the largest group of inactive TBs had permanently exited the racing industry (45% retired, 5.3% deceased). A relatively large group exited racing temporarily (43%) but participated in the racing industry in the following season. The reasons for retirement were predominantly voluntary, such as poor performance or owner's request. Almost one third of retirements were due to injuries with tendon or ligament problems the most frequently conditions listed. The median age at retirement was five (Q1 4; Q3 7) years. Extrapolation of the survey results to the population of horses racing or training in Australia in 2017-2018 (n = 37,750) show that that 17% of the population retire each year and 2.1% die. These estimates provide benchmarks for industry and animal welfare organisations to resource and measure the effectiveness of interventions.

Sudden death caused by spinal cord injury associated with vertebral fractures and fetlock failure in a Thoroughbred racehorse.

The most prevalent causes of death in racehorses are musculoskeletal injuries, causing ~83% of deaths within the racing industry in California and elsewhere. The vast majority of these injuries have preexisting lesions that predispose to fatal injury. A 4-y-old Thoroughbred colt suffered an acute suspensory apparatus failure, including biaxial proximal sesamoid bone fractures of the right front fetlock, causing loss of support of the fetlock joint and consequent fall with fractures of the cervical and sacral spine. Cervical fracture caused spinal cord damage that resulted in sudden death. A preexisting lesion in the medial proximal sesamoid bone likely predisposed to complete fracture of this bone and fetlock breakdown. Interestingly, a comparable osteopenic lesion was present in the intact medial proximal sesamoid bone of the left forelimb, which is consistent with bilateral repetitive overuse injury in racehorses. The morphologic features of the cervical and sacral spine fractures were compatible with acute injury; no evidence of preexisting lesions was seen. Most likely, these acute vertebral fractures occurred as a result of the horse falling. This case emphasizes the importance of performing a detailed autopsy in horses that suffer an appendicular musculoskeletal injury, particularly in fatal cases when the horse dies following a leg injury.

The treatment of articular cartilage injuries with mesenchymal stem cells in different animal species.

One of the major problems observed in veterinary practice is articular cartilage injuries in animals. In terms of agriculture, it leads to their culling from the herd, even if they are highly productive animals. With companion animals, owners usually have to decide between euthanasia or long-term sometimes lifelong treatment of the injury by a veterinarian. The use of mesenchymal stem cells (MSCs) for the treatment of cartilage injury in veterinary medicine is based on the good results observed in preclinical studies, where large animals have been used as experimental models to study the regenerative activity of MSCs. According to the literature, MSCs in veterinary medicine have been used to treat cartilage injury of dogs and horses, whereas sheep and goats are generally models for reproducing the disease in preclinical experimental studies.

Modelagem farmacocinética/farmacodinâmica do florfenicol para o tratamento da adenite equina por meio da simulação de Monte Carlo / Pharmacokinetic/pharmacodynamic modeling of florfenicol for the treatment of equine adenitis using Monte Carlo simulation

O objetivo deste trabalho foi avaliar a eficácia do florfenicol na dose usualmente empregada em equinos de 22 mg/kg pelas vias intravenosa, intramuscular e oral para o tratamento de adenite equina por Streptococcus equi. subsp. equi, usando a modelagem farmacocinética/farmacodinâmica (PK/PD – Pharmacokinetic/Pharmacodynamic) e a simulação de Monte Carlo. Foi realizada uma simulação de Monte Carlo a partir dos parâmetros PK, logo depois, efetuou-se a modelagem PK/PD para determinar as taxas de eficácia do antimicrobiano para o tratamento dessa infecção bacteriana, de acordo com o valor da concentração inibitória mínima (CIM), em um intervalo de CIM de 0,125 – 4 μg/mL. Pela via intravenosa, a probabilidade de erradicação bacteriana foi de 100% para CIM até 0,5 μg/mL e efeito bacteriostático com probabilidades de 99% e 80% para CIMs de 2 e 4 μg/mL, respectivamente. Já pelas vias intramuscular e oral a probabilidade de se atingir o índice de erradicação bacteriológica foi de 100% para CIM de até 0,5 μg/mL, contudo, atinge valores de 80% e 81%, respectivamente, para CIM de 1 μg/mL considerando o efeito bactericida (p<0,01). Portanto, através desse estudo é evidenciado a eficácia do florfenicol até a CIM de 0,5 μg/mL para as três vias de administração citadas, entretanto, para CIMs superiores a esse valor, é imprescindível o ajuste da dose farmacológica, evitando falhas na terapêutica e possível resistência microbiana.

The objective of this study was to evaluate the efficacy of florfenicol at the dose usually used in horses of 22 mg/kg by intravenous, intramuscular and oral routes for the treatment of equine adenitis caused by Streptococcus equi. subsp. equi, using Pharmacokinetic/Pharmacodynamic (PK/PD) modeling and Monte Carlo simulation. A Monte Carlo simulation was performed from the PK parameters, then PK/PD modeling was performed to determine the antimicrobial efficacy rates for the treatment of this bacterial infection, according to the minimum inhibitory concentration (MIC) value, in a MIC range of 0.125 - 4 μg/mL. Intravenously, the probability of bacterial eradication was 100% for MICs up to 0.5 μg/mL, and the bacteriostatic effect was 99% and 80% for MICs of 2 and 4 μg/mL, respectively. However, for the intramuscular and oral routes, the probability of reaching the bacteriologic eradication index was 100% for MICs of up to 0.5 μg/mL, however, it reaches values of 80% and 81%, respectively, for MICs of 1 μg/mL considering the bactericidal effect (p<0.01). Therefore, through this study the efficacy of florfenicol is evidenced up to the MIC of 0.5 μg/mL for the three routes of administration cited, however, for MICs higher than this value, it is essential to adjust the pharmacological dose, avoiding failures in therapy and possible microbial resistance.

Ex vivo comparison of standing and recumbent repair of incomplete parasagittal fractures of the first phalanx in horses.

OBJECTIVE: To assess suspensory ligament extensor branch location and fracture gap reduction with simulation of standing and recumbent cortical bone screw repair of experimental incomplete parasagittal proximal phalanx (P1) fractures. STUDY DESIGN: Controlled laboratory study. SAMPLE POPULATION: Twenty equine cadaver forelimbs. METHODS: Simulated fractures were repaired twice in random order. A proximal cortical bone screw was placed in lag fashion with the limb unloaded (simulated recumbent repair) and loaded to 38% of body weight (range, 375-568 kg; simulated standing repair). Changes in fracture gap width were assessed on computed tomography (CT) images and with intraplanar force-sensitive resistors measuring voltage ratios (V△ ) between loaded recumbent (R-1) and standing repair simulations (R-2). Extensor branch borders were determined relative to implant position and sagittal P1 width on transverse CT images. P ≤ .05 was considered significant. RESULTS: Standing repair simulation-associated fracture gaps were not wider than in R-1 while controlling for confounding factors (loading weight, implant position, or animal age; P > .7, repeated-measures analysis of variance). Voltage ratio data associated with R-2 were not smaller than with R-1 (mean difference, 0.002 ± 0.052; one-sided Wilcoxon signed-rank test, P = .27). More of P1 width was approachable palmar to extensor branches when limbs were loaded (0.804 ± 0.314 cm) vs unloaded (0.651 ± 0.31 cm; paired Student's t test, P < .001). CONCLUSION: Simulated standing repair was not associated with inferior fracture reduction compared with loaded simulations of recumbent repairs. Limb loading affected extensor branch location relevant to implant positioning. CLINICAL SIGNIFICANCE: Unloading during standing repair of incomplete parasagittal proximal P1 fractures may not be required to optimize fracture reduction.

Polyaxial pedicle screw external fixation to stabilize oblique mandibular fractures in three standing, sedated horses.

OBJECTIVE: To report the radiographic, surgical and postoperative features in horses with unstable oblique mandibular fractures secured with polyaxial pedicle screws (PPS) external fixation construct and intraoral wiring. ANIMALS: Three client-owned horses. STUDY DESIGN: Short case series. METHODS: Two horses each had a unilateral fracture, which did not improve after conservative management, and one horse had bilateral fractures. Clinical and radiographic features were documented. Polyaxial pedicle screw external fixators and intraoral tension band wiring were applied in standing horses after combining sedation and regional nerve anesthesia. Intraoral wires were implanted through a lateral buccotomy between teeth (two horses) or burred through exposed crown (one horse) and then secured around the incisors. The PPS were inserted under radiographic guidance to avoid tooth roots. Healing was assessed with radiographic examination. The PPS external fixator rod and intraoral wires were removed first. The mandible was manipulated, and, if it was stable, the PPS were removed. RESULTS: Implants were removed at 6, 8, or 10 weeks after the mandibles were palpably stable. Complications included broken wires in one horse, bone sequestration in one horse, and infection in one horse. Follow-up communication with the owners 12 to 18 months later confirmed complete healing without further complications of the fractured mandibles or teeth. CONCLUSION: Polyaxial pedicle screw external fixation led to fracture healing and a return to function in all three horses. The complications encountered did not preclude a successful outcome. CLINICAL SIGNIFICANCE: Polyaxial pedicle screw external fixation coupled with intraoral wiring provides an alternative to treat unstable equine mandibular fractures without general anesthesia.

Avaliação ultrassonográfica dos tendões flexores dos membros anteriores em equinos de vaquejada na microrregião do Alto Médio Gurgueia, Sul do Piauí, Brasil / Ultrasound evaluation of the flexor tendons of the forelimbs in horses in vaquejada horses in theAlto Médio Gurgueia, South of Piauí, Brazil

Objetivou-se com este estudo demonstrar a influência do tipo de treinamento sobre as medidas dos tendões flexores palmares em equinos de vaquejada que correm à direita do boi na microrregião do Alto Médio Gurgueia, Sul do Piauí, Brasil. Foram utilizados oito animais, da raça quarto de milha e seus mestiços, de diferentes idades, peso e sexo, selecionados e questionados sobre o tempo que exerciam a atividade de vaquejada e o tipo de treinamento a qual eram submetidos, que refere-se a maneira como praticavam a prova correndo de que lado do boi, em uma prova de vaquejada no município de Cristino Castro, Sul do Piauí, Brasil, onde os participantes eram provenientes de diferentes haras da Microrregião do Alto Médio Gurgueia, Sul do Piauí, Brasil. Em cada animal foi realizada ultrassonografia das zonas IB, IIB e IIIB dos tendões flexores digital superficial (TFDS) e digital profundo (TFDP), obtendo-se as medidas dos diâmetros médio lateral (DML) e dorso palmar (DDP) através do plano transverso em cada uma das diferentes zonas. Os dados foram submetidos a análise estatística (ANOVA), utilizando-se o teste t a nível de significância de (p<0,05), observando-se que não houve diferença significativa entre as medidas avaliadas. De acordo com os resultados obtidos, cavalos atletas que correm a direita do boi não apresentam diferença significativa nos diâmetros médio lateral e dorso palmar dos tendões flexores entre os antímeros direito e esquerdo do membro torácico.

The objective of this study was to demonstrate the influence of the type of training on the measurements of the palmar flexor tendons in vaquejada horses that run to the right of the ox in the microregion of the Alto Médio Gurgueia, South of Piauí, Brazil. Eight animals of the quarter-mile breed and their crossbreed, of different ages, weight and sex, were selected and asked about the time they were engaged in the activity of the vaquejada and the type of training they were submitted to as they practiced running on which side of the ox, in a vaquejada test in the municipality of Cristino Castro, South of Piauí, Brazil, where the participants came from different farms of the microregion of the Alto Médio Gurgueia, South of Piauí, Brazil. The ultrasonography of the IB, IIB and IIIB zones of the superficial digital (TFDS) and deep digital flexor tendons (TFDP) were performed in each animal, obtaining the measurements of the lateral diameters (DML) and palmar dorsum (DDP) through the transverse plane in each of the different zones. Data were submitted to statistical analysis (ANOVA), using the t test at the significance level of (p <0.05), observing that there was no significant difference between the measures evaluated. According to the results, horses for vaquejada athletes do not present significant difference in the lateral diameters and palmar dorsum of the flexor tendons between the right and left thoracic limb antimeres.

Avaliação ultrassonográfica dos tendões flexores dos membros anteriores em equinos de vaquejada na microrregião do Alto Médio Gurgueia, Sul do Piauí, Brasil / Ultrasound evaluation of the flexor tendons of the forelimbs in horses in vaquejada horses in the Alto Médio Gurgueia, South of Piauí, Brazil

Objetivou-se com este estudo demonstrar a influência do tipo de treinamento sobre as medidas dos tendões flexores palmares em equinos de vaquejada que correm à direita do boi na microrregião do Alto Médio Gurgueia, Sul do Piauí, Brasil. Foram utilizados oito animais, da raça quarto de milha e seus mestiços, de diferentes idades, peso e sexo, selecionados e questionados sobre o tempo que exerciam a atividade de vaquejada e o tipo de treinamento a qual eram submetidos, que refere-se a maneira como praticavam a prova correndo de que lado do boi, em uma prova de vaquejada no município de Cristino Castro, Sul do Piauí, Brasil, onde os participantes eram provenientes de diferentes haras da Microrregião do Alto Médio Gurgueia, Sul do Piauí, Brasil. Em cada animal foi realizada ultrassonografia das zonas IB, IIB e IIIB dos tendões flexores digital superficial (TFDS) e digital profundo (TFDP), obtendo-se as medidas dos diâmetros médio lateral (DML) e dorso palmar (DDP) através do plano transverso em cada uma das diferentes zonas. Os dados foram submetidos a análise estatística (ANOVA), utilizando-se o teste t a nível de significância de (p<0,05), observando-se que não houve diferença significativa entre as medidas avaliadas. De acordo com os resultados obtidos, cavalos atletas que correm a direita do boi não apresentam diferença significativa nos diâmetros médio lateral e dorso palmar dos tendões flexores entre os antímeros direito e esquerdo do membro torácico.

The objective of this study was to demonstrate the influence of the type of training on the measurements of the palmar flexor tendons in vaquejada horses that run to the right of the ox in the microregion of the Alto Médio Gurgueia, South of Piauí, Brazil. Eight animals of the quarter-mile breed and their crossbreed, of different ages, weight and sex, were selected and asked about the time they were engaged in the activity of the vaquejada and the type of training they were submitted to as they practiced running on which side of the ox, in a vaquejada test in the municipality of Cristino Castro, South of Piauí, Brazil, where the participants came from different farms of the microregion of the Alto Médio Gurgueia, South of Piauí, Brazil. The ultrasonography of the IB, IIB and IIIB zones of the superficial digital (TFDS) and deep digital flexor tendons (TFDP) were performed in each animal, obtaining the measurements of the lateral diameters (DML) and palmar dorsum (DDP) through the transverse plane in each of the different zones. Data were submitted to statistical analysis (ANOVA), using the t test at the significance level of (p <0.05), observing that there was no significant difference between the measures evaluated. According to the results, horses for vaquejada athletes do not present significant difference in the lateral diameters and palmar dorsum of the flexor tendons between the right and left thoracic limb antimeres.

Ex vivo study of vagal branches at risk for iatrogenic injury during laryngoplasty in horses.

OBJECTIVE: To localize vagal branches within the surgical field of laryngoplasty and identify potentially hazardous surgical steps. STUDY DESIGN: Observational cadaveric study. SAMPLE POPULATION: Five equine head-neck specimens and four entire equine cadavers. METHODS: Dissection of the pharyngeal region from a surgical perspective. Neuronal structures were considered at risk if touched or if the distance to instruments was less than 5 mm. RESULTS: The branches of the pharyngeal plexus (PP) supplying the cricopharyngeal muscle (PPcr), the thyropharyngeal muscle (PPth), and the esophagus (PPes) were identified in the surgical field in nine of nine, five of nine, and one of nine specimens, respectively. The internal branch of the cranial laryngeal nerve (ibCLN) was identified within the carotid sheath in six of nine specimens. The external branch of the cranial laryngeal nerve (ebCLN) was identified close to the septum of the caudal constrictors in nine of nine specimens. The blade of the tissue retractor compressed the ibCLN in six of six, the ebCLN in four of six, the PPcr in six of six, the PPth in two of three, and the PPes in two of two specimens in which the respective nerves were identified after further dissection. Surgical exploration of the dorsolateral aspect of the pharynx and the incision of the septum of the caudal constrictors harmed the ebCLN in nine of nine, PPcr in seven of nine, and PPth in four of eight specimens. CONCLUSION: Several vagal branches were located in the surgical field and must be considered at risk because of their location. CLINICAL SIGNIFICANCE: Use of the tissue retractor, dissection over the pharynx, and dissection of the septum of the caudal constrictors involve a risk to damage vagal branches.

Effect of infrared and red monochromatic light on equine wound healing.

BACKGROUND: Light-emitting diodes (LEDs) are commonly used for treating a variety of disorders in horses, including wounds. Despite its claim to shorten healing times, there is a lack of scientific documentation regarding its effects. OBJECTIVES: To investigate if treatment with pulsating visible red light (λ ≈ 637 nm) and near-infrared (NIR) light (λ ≈ 956 nm) affects wound healing. STUDY DESIGN: Randomised blinded controlled experimental study. METHODS: A circular skin wound (Ø = 2 cm) was created on each side of the neck in eight healthy horses. One randomly chosen wound received light treatment and the other served as an untreated control. Treatment duration was 4 minutes and 40 seconds (red light 95 seconds, 2.3 mW/cm2 ; NIR light 185 seconds, 6.4 mW/cm2 ) and was performed once daily on day 0-4, 7-11, 14-18 and 21-25. The wounds were photographed and evaluated using digital photoplanimetry on day 0, 1, 2, 3, 4, 7, 14, 21, 28 and 35. The degree of swelling was assessed with diagnostic ultrasound on the same days except the last recording was performed on day 36 instead of 35. Days to total healing was recorded. ANOVA was used for statistical analysis (P < .05). RESULTS: The wound area (P = .2-.9) and degree of swelling (P = .2-1.0) did not differ between treated and control groups on any day. There was a significant difference (P = .03) in healing time between control (49.0, 95% CI = 35.4-62.6 days) and treated wounds (51.8, 95% CI = 38.7-64.8 days). MAIN LIMITATIONS: The wounds were treated until day 25 and this study does not investigate the effect of a longer treatment period than 25 days. CONCLUSIONS: The results of this study do not indicate any clinically relevant positive effect of pulsating visible red light and NIR light on the healing of experimental skin wounds in horses, compared with no treatment.

Horse welfare at slaughter: A novel approach to analyse bruised carcasses based on severity, damage patterns and their association with pre-slaughter risk factors.

The study presents a novel veterinary forensic approach to analyse the bruising of horse carcasses, based on the nature of the bruises and how they are grouped in certain anatomical areas. Data on pre-slaughter logistics was obtained for 113 journeys with horses that travelled from Mexico and the USA to a Mexican abattoir. We found that carcass bruising was a highly prevalent problem (79% of carcasses had bruising) and was especially problematic in journeys lasting longer than 12 h, independently of the animal's country of origin, sex, age, lairage time or vehicle type. Multivariable logistic regression showed that the most severe bruises were not dispersed randomly on the carcass and that their distribution was associated with the presence of medium-sized bruises on the abdominal wall, front and rear limb. Cluster analysis suggested four damage patterns based on bruise location: severe and concentrated bruising, as well as non-severe bruises on the rear limb, thoracic-wall or more dispersed throughout the carcass.

Non-weight bearing ultrasonographic examination allows the diagnosis of longitudinal fiber disruption (split) in equine suspensory ligament branches not visible on weight bearing examination.

When evaluating suspensory ligament branch splits, there is a discrepancy between high field MRI findings and weight bearing ultrasonographic imaging characteristics. In this descriptive and retrospective case series, ultrasonographic examination was performed on suspensory ligament branches with the limbs in weight bearing and non-weight bearing positions. Suspensory ligament branch splits were defined as linear regions of decreased echogenicity when imaged with the limb in a weight bearing position that increased in size and became anechoic with the limb in a non-weight bearing position. This appearance was considered an indication of pathologic change in the branch. A total of 62 suspensory ligament branches were included in the study from 37 horses, with 14 partial splits, 11 intrasubstance splits, and 14 complete splits of which two had extension of fetlock synovial fluid and synovial membrane through the split. Recheck ultrasonographic examinations performed in eight horses up to 14 months following the initial examination demonstrated persistence of the split in two horses, partial resolution in five horses, and complete resolution in one horse. Ultrasonographic examination using the non-weight bearing approach proved valuable for increasing the lesion conspicuity as compared to the weight bearing images. Certain abnormalities, such as longitudinal fiber disruption (split) in suspensory ligament branches may only be evident when imaged non-weight bearing. The use of this technique provides a more accurate representation of lesion severity and allows for monitoring over time. A longitudinal study is necessary to determine the clinical relevance of suspensory ligament branch splits.

Application of gene therapy in the treatment of superficial digital flexor tendon injury in horses.

Background: Tendon injuries are one of the most common causes of orthopedic disorders in horses. Such injuries involve a long course of treatment and recovery. The most promising method of treating these injuries is the use of recombinant proteins and gene therapy. Aim: In this work, we evaluated the therapeutic efficacy of plasmid DNA (pDNA) containing two species-specific coding sequences, i.e. vascular endothelial growth factor 164 (VEGF164) and fibroblast growth factor 2 (FGF2), in the treatment of severe damage to the tendon of the superficial digital flexor. Methods: A pDNA construct was used to restore the damaged superficial digital flexor tendon in the horse. Results: This study showed that the administration of pDNA encoding VEGF164 and FGF2 genes at the injury area increased the regenerative activities of the damaged tendon. Conclusion: This study shows the therapeutic properties of genetic constructs (pDNA) and contributes to the advancements in the use of these therapies.

Lombalgia em equinos de vaquejada: achados clínicos, ultrassonográficos e resultados terapêuticos de 25 casos / Back pain in vaquejada horses: clinical, ultrasound findings and therapeutic outcome in 25 cases

Vinte e cinco equinos da raça Quarto de Milha, em atividade esportiva na modalidade de vaquejada no estado do Rio Grande do Norte, Brasil, 15 machos e 10 fêmeas, com idade média de 7,91 + 3,26 anos, foram examinados na propriedade de origem ou centro de treinamento para diagnóstico de baixo desempenho associado a dor lombar. O exame clínico da região toracolombar foi realizado por meio da inspeção, palpação, ultrasonografia, testes de mobilização (ventro e dorsoflexão toracolombar; flexão lateral e rotação toracolombar; flexão lateral e rotação cervical e torácica) além de análise do animal em movimento. As principais alterações encontradas foram miosite epaxial, desmite supra-espinhosa, além de atrofia do músculo multifidus. O tratamento clínico consistiu na administração de injeções periespinhais de Acetonida de triancinolona numa dose total de 200mg, além de exercício controlado. Após o tratamento, todos os animais retornaram a desempenhar suas atividades atlética em nível de desempenho superior ou igual ao demonstrado antes do diagnóstico e tratamento da lombalgia.

Twenty five horses of the Quarter horse breed, in sporting activity in the vaquejada modality in the state of Rio Grande do Norte, Brazil, 15 males and 10 females, with an average age of 7.91 + 3.26 years, were examined in the property of origin or training center for low performance diagnosis associated with low back pain. The clinical examination of the thoracolumbar region was performed through inspection, palpation, ultrasonography, mobilization tests (ventral and thoracolumbar dorsoflexion; lateral flexion and thoracolumbar rotation; lateral flexion and cervical and thoracic rotation) in addition to analysis of the animal in motion. The main changes found were epaxial myositis, supraspinatus desmite, as well as atrophy of the multifidus muscle. Clinical treatment consisted of administering perispinal injections of triamcinolone Acetonide in a total dose of 200mg, in addition to controlled exercise. After treatment, all animals returned to performing their athletic activities at a performance level greater than or equal to that demonstrated before the diagnosis and treatment of low back pain.

Equine heterotopic polyodontia: a case report / Poliodontia heterotópica equina: relato de caso / Poliodontia heterotópica equina: relato de caso

Heterotopic polyodontia have been described in most domestic species. Known as a dentigerous cyst but appropriately called heterotopic polyiodontics, it rarely occurs in horses, however it is easily recognized as a congenital defect. The cysts usually associated with this condition contain part or all of dental structures. The heterotopic tooth or dental structure is usually adhered to the temporal bone and surrounded by a secretory membrane, with a accumulation of exudate and draining tract along the proximal pinna or directly over the cyst. This case report describes in a 2.5-year-old female quarter horse, weighing 430 kg, with a heterotopic polyodontia that contained two easily small's identifiable dental structures, presented for evaluation of a chronic intermittent mucopurulent exudate discharge from the right sub-auricular region in the mastoid process of the temporal bone and a drainage tract near the right pinna. The diagnosis is established with clinical, radiographic, ultrasound and confirmed by histopathological examination of the structures removed. The cystic capsule was surgically removed, measuring approximately 3.0 x 2.3 cm in diameter, filled with mucopurulent exudate and containing two dental structures within 0.5 cm in diameter and 0.2 cm in diameter. Microscopic examination revealed a cystic area covered by stratified squamous epithelium with a lympho-histio-plasmatic cell infiltrate in the dermis, which was compatible with heterotopic polyodontia. Postoperatively, there were no neuromotor sequelae and wound healing evolved positively.(AU)

A poliodontia heterotópica tem sido descrita na maioria das espécies domésticas. Conhecido como cisto dentígero, mas apropriadamente denominado poliodontia heterotópica, raramente ocorre em equinos, porém é facilmente reconhecido como defeito congênito. Os cistos geralmente associados a essa condição contêm parte ou toda as estruturas dentarias. O dente heterotópico ou estrutura dentaria é comumente encontrado aderido ao osso temporal e envolvido por uma membrana secretora, com acúmulo de exsudato e trajeto de drenagem ao longo do pavilhão auricular proximal ou diretamente sobre o cisto. Este relato descreve um caso de em um equino,fêmea, quarto de milha, com 2,5 anos de idade, pesando 430 kg, com poliodontia heterotópica que continha duas estruturas dentarias facilmente indentificadas, apresentando um orifício na região sub-auricular direita no processo mastóideo do osso temporal, com secreção mucopurulenta intermitente e crônica, próximo ao pavilhão auricular direito. O diagnóstico foi estabelecido com exame clínico, radiográfico, ultrassonográfico e confirmado pelo exame histopatológico das estruturas retiradas. A cápsula cística foi removida cirurgicamente medindo aproximadamente 3,0 x 2,3 cm de diâmetro, preenchida com exsudato mucopurulento e contendo em seu interior duas estruturas dentárias medindo cerca de 0,5 cm de diâmetro e 0,2 cm de diâmetro. O exame microscópico revelou área cística revestida por epitélio escamoso estratificado com infiltrado linfo-histo-plasmocitário na derme, compatível com poliodontia heterotópica. No pós-operatório não houve sequelas neuromotoras e a cicatrização da ferida evoluiu positivamente.(AU)

La poliodontia heterotópica ha sido descrita en la mayoría de las especies domésticas. Conocido como quiste dentígero, pero apropiadamente llamado poliodontia heterotópica, raramente ocurre en equinos, sin embargo se reconoce fácilmente como un defecto congénito. Los quistes generalmente asociados a esa condición contienen parte o la totalidad de las estructuras dentales. El diente heterotópico o estructura dental se encuentra comúnmente adherido al hueso temporal y rodeado por una membrana secretora, con acumulación de exudado y vía de drenaje a lo largo del pabellón auricular proximal o directamente sobre el quiste. En este informe se describe el caso de una hembra, cuarto de milla, de 2,5 años de edad, con 430 kg de peso, presentando poliodontia heterotópica que contenía dos estructuras dentales fácilmente identificables, con un orificio en la región subauricular derecha en el proceso mastoides del hueso temporal, secreción mucopurulenta intermitente y crónica próximo al oído derecho. El diagnóstico se estableció con examen clínico, radiográfico, ecográfico y se confirmó con el examen histopatológico de las estructuras extirpadas. La cápsula quística se extrajo quirúrgicamente midiendo aproximadamente 3,0 x 2,3 cm de diámetro, rellena con exudado mucopurulento y conteniendo en su interior dos estructuras dentales que medían aproximadamente 0,5 cm de diámetro y 0,2 cm de diámetro. El examen microscópico reveló una zona quística cubierta por un epitelio escamoso estratificado con infiltrado linfo-histo-plasmocítico en la dermis, compatible con poliodontia heterotópica. En el postoperatorio no se produjeron secuelas neuromotoras y la cicatrización de la herida evolucionó positivamente.(AU)

Tensile strength and early healing of self-locking and surgeon's knots.

OBJECTIVE: To compare the biomechanical properties and healing of ventral midline celiotomies (VMC) closed with a self-locking knot combination and forwarder start and Aberdeen end (F-A) vs a traditional knot combination and surgeon's start and end (S-S). STUDY DESIGN: In vivo, experimental. ANIMALS: Twenty-one horses. METHODS: Fourteen horses underwent VMC, which was closed with either an F-A (n = 7) or an S-S (n = 7) knot combination. Incisions were subjectively graded by masked evaluators for dehiscence, edema, and drainage. Biomechanical testing was performed on three abdominal segments, and histology was performed on one segment from each animal after humane euthanasia 10 days post-VMC. The abdominal wall of control horses (n = 7, no celiotomy) was collected for biomechanical testing. RESULTS: Forwarder start and Aberdeen end and S-S horses had less tensile strength compared with control horses (P ≤ .001). No differences were detected between treatment groups for any variable evaluated, including tensile strength (P = .975), location of failure (P = .240), and histologic healing at the knot (P = .600). CONCLUSION: Closure of VMC with self-locking knots resulted in biomechanical and healing features similar to those with a traditional closure technique, with neither restoring the tensile strength of the linea alba. CLINICAL SIGNIFICANCE: Results of this study provide evidence to support a clinical trial to evaluate long-term performance of the F-A self-locking knot closure in horses.