Ex vivo biomechanical evaluation of polyester and polyblend suture techniques to perform equine laryngoplasty.

OBJECTIVE: To validate the use of a polyblend tape suture in equine laryngoplasty (PL). STUDY DESIGN: Experimental study. ANIMALS: Thirty-two cadaveric larynges. METHODS: Each larynx was randomly assigned to 1 of 4 groups: PL with polyblend tape suture (TigerTape), without (TT) or with a cannula (TTC) in the muscular process of the arytenoid cartilage, and PL with polyester suture (Ethibond), without (EB) or with a cannula (EBC). Construct stiffness, total migration, creep, and drift values were measured after 3000 cycles. The specimens were then loaded to failure to assess their residual properties: load at failure, total energy, displacement, and 2 stiffness coefficients. RESULTS: After cyclic testing, the total migration and creep were lower in TTC (6.36 ± 1.20 mm; 1.35 ± 0.38 mm/s) than in EB (11.12 ± 4.20 mm; 3.39 ± 2.68 mm/s) and in the TT constructs (11.26 ± 1.49 mm; 3.20 ± 0.54 mm/s); however, no difference was found with EBC (9.19 ± 3.18 mm; 2.14 ± 0.99). A correlation was found between total migration and creep (R = .85). The TTC constructs failed at higher loads (129.51 ± 33.84 N) than EB (93.16 ± 18.21 N) and EBC (81.72 ± 13.26 N) whereas the EB and EBC constructs were less stiff than TT and TTC (P < .001). CONCLUSION: Biomechanical properties were generally superior for the TTC constructs tested under cyclical loading. The TT and TTC constructs failed at a higher load than EB and EBC constructs. The cannula in TTC and EBC reduced the failure at the muscular process. CLINICAL SIGNIFICANCE: These results provide evidence to support the in vivo evaluation of the polyblend tape suture with or without a cannula in the muscular process for laryngoplasty in horses.

IMAGING DIAGNOSIS - USE OF MULTIPHASE COMPUTED TOMOGRAPHIC UROGRAPHY IN THE DIAGNOSIS OF URETERAL TEAR IN A 6-DAY-OLD FOAL.

A 6-day-old foal was evaluated for depression and inappetence. After initial stabilization, the filly developed a hypochloremic metabolic alkalosis and persistent hypercreatinemia. Abdominal ultrasound revealed fluid accumulation around the left kidney and a well-defined rounded fluid filled structure dorsal to the urinary bladder. Computed tomography revealed a partial tear of the left ureter with distension of the retroperitoneal membrane. Exploratory celiotomy was performed to allow left kidney nephrectomy. At 6 months follow-up, the filly was growing normally without complications. Ultrasound and CT imaging in this case provided an accurate diagnosis and a presurgical aid to select the appropriate therapeutic approach.

Ultrasonographic findings in 38 horses with septic arthritis/tenosynovitis.

Septic arthritis/tenosynovitis in the horse can have life-threatening consequences. The purpose of this cross-sectional retrospective study was to describe ultrasound characteristics of septic arthritis/tenosynovitis in a group of horses. Diagnosis of septic arthritis/tenosynovitis was based on historical and clinical findings as well as the results of the synovial fluid analysis and/or positive synovial culture. Ultrasonographic findings recorded were degree of joint/sheath effusion, degree of synovial membrane thickening, echogenicity of the synovial fluid, and presence of hyperechogenic spots and fibrinous loculations. Ultrasonographic findings were tested for dependence on the cause of sepsis, time between admission and beginning of clinical signs, and the white blood cell counts in the synovial fluid. Thirty-eight horses with confirmed septic arthritis/tenosynovitis of 43 joints/sheaths were included. Degree of effusion was marked in 81.4% of cases, mild in 16.3%, and absent in 2.3%. Synovial thickening was mild in 30.9% of cases and moderate/severe in 69.1%. Synovial fluid was anechogenic in 45.2% of cases and echogenic in 54.8%. Hyperechogenic spots were identified in 32.5% of structures and fibrinous loculations in 64.3%. Relationships between the degree of synovial effusion, degree of the synovial thickening, presence of fibrinous loculations, and the time between admission and beginning of clinical signs were identified, as well as between the presence of fibrinous loculations and the cause of sepsis (P ≤ 0.05). Findings indicated that ultrasonographic findings of septic arthritis/tenosynovitis may vary in horses, and may be influenced by time between admission and beginning of clinical signs.

Return to sport activity following ultrasonographic diagnosis and conservative management of spontaneous injuries of the serratus cervicis ventralis and serratus thoracis ventralis muscles in 11 endurance horses.

OBJECTIVE: To describe the clinical diagnosis, ultrasound findings, and outcome of 11 endurance horses with injuries to the serratus ventralis thoracis (SVT) or serratus ventralis cervicis (SVC) muscle. ANIMALS: 11 endurance horses competing in medium- to high-level competitions and presenting with lameness caused by injuries to the SVT or SVC muscle, as confirmed by ultrasonography. CLINICAL PRESENTATION: Physical examinations revealed swelling caudal to the shoulder region associated with dorsocranial displacement of the scapula and edema of the ventral thorax for horses with SVT injuries. Swelling cranial to the scapula and edema of the pectoral area were identified among horses with injuries to the SVC. RESULTS: Dynamic examinations revealed moderate-to-severe reduction of the cranial phase of the stride at the walk; at the trot, a lameness score of 2 to 3/5 was assigned (modified American Association of Equine Practitioners Lameness Scale). Ultrasonography revealed moderate-to-severe increases in size of the muscle body, heterogeneous echogenicity, loss of the striated muscle pattern, and varying degrees of perimuscular edema. All horses were able to resume full training and competition in an average of 216 days (range, 74 to 362 days) and 148 days (range, 112 to 309 days) for injuries of the SVT and SVC, respectively. CLINICAL RELEVANCE: This case series is the first to describe the clinical and ultrasonographic features of spontaneous injuries to the SVT or SVC. Ultrasonography for diagnosis was simple and well tolerated by the horses.

Long-term outcomes of the Italian Mycobacterium avium subspecies paratuberculosis control programme for dairy cattle.

BACKGROUND: The considerable epidemiological and economic implications of paratuberculosis, caused by Mycobacterium avium subspecies paratuberculosis (MAP), have placed importance on control efforts aimed at preventing MAP transmission. In this context, Italy issued national guidelines for the control and status certification of MAP in dairy cattle in 2013. METHODS: We assessed the long-term outcomes of the Italian MAP control programme for 14 dairy farms located in northern Italy by retrospectively reviewing the results of yearly serological tests, presence of clinical cases, MAP faecal shedding in serologically positive animals, farm management and health ranking as indicators of herd health between 2014 and 2021. RESULTS: A significantly higher number of serologically positive animals were observed between 2014 and 2016 than between 2017 and 2021, as well as an improving trend in the paratuberculosis health ranking for nine of the 14 farms. No clinical cases were reported. MAP shedding was detected in 9.4% of serologically positive animals. Discarding colostrum and prioritised culling of seropositive animals assisted by adoption of standardised serological testing were presumed to have a key role in MAP control, despite the reluctance of some farmers to address hygienic issues and improve the separation of calves from adult animals. LIMITATIONS: The small number of farms included in this study and the fact that these were not randomly selected may limit the generalisability of the findings. CONCLUSIONS: The Italian paratuberculosis control plan has provided measures to limit the uncontrolled spread of MAP infection within and between herds by promoting animal trading between farms certified as negative or low risk.

Ultrasonographic findings of fluid accumulation and hyperechogenic spots suggestive of surgical site infection following laparotomy for colic in horses.

BACKGROUND: The aim of this study was to compare ultrasonographic findings of the ventral midline incision after exploratory laparotomy for colic in horses with and without surgical site infection (SSI). METHODS: Ultrasonographic examination of the surgical wound was performed on postoperative day 5 (D5) and day 10 (D10) to assess the presence of fluid accumulation, suture sinus formation, hyperechogenic spots and fistulous path. Clinical evaluation of the wound was used to classify horses with and without SSI. The accuracy, sensitivity, specificity and positive and negative predictive values of the ultrasonographic findings were then calculated. Multivariable logistic regression analyses were performed with SSI as a dependent variable and age, sex, breed and ultrasonographic findings as independent variables after univariate and collinearity analyses. RESULTS: Twenty-nine of the 84 horses examined had an SSI. Detection of fluid accumulation and hyperechogenic spots increased the odds for SSI at D5 (odds ratio [OR]: 4.99, 95% confidence interval [CI]: 1.53-16.33, p = 0.008; OR: 10.78, 95% CI: 1.75-26.59, p = 0.01, respectively) and D10 (OR: 11.51, 95% CI: 2.39-55.47, p = 0.002; OR: 12.34, 95% CI: 3.45-44.15, p < 0.001, respectively). LIMITATION: Ultrasonographic images were taken only on the longitudinal section. CONCLUSION: Ultrasonographic examination is helpful in evaluating the surgical incision after laparotomy, with the detection of fluid accumulation and hyperechogenic spots surrounding the sutures being strongly related to SSI.

Lesion Distribution in the Metacarpophalangeal and Metatarsophalangeal Region of 341 Horses Using Standing Magnetic Resonance Imaging.

Pain localised to the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) region represents a frequent cause of lameness in sport horses, and standing magnetic resonance imaging (MRI) of these regions is increasingly being acquired. This multicentre retrospective study describes the ranges of abnormalities identified on standing MRI of the MCP/MTP region and compares patterns of abnormalities between forelimbs, hindlimbs and different sports disciplines. In total, 341 MRI reports were reviewed. Subchondral bone plate irregularities, condylar and proximal phalanx pathologies were frequently identified with subchondral bone defect, sclerosis and increased intensity on STIR images often described. Medial pathology was frequently identified in the forelimbs, and more lateral pathology was reported in the hindlimbs, which could potentially reflect differences in the loading patterns. Significant differences in MRI findings were found between different sports activities, with MCP/MTP bone pathology occurring more frequently in MRI reports from race and endurance horses and MCP/MTP soft tissue injuries being reported more frequently in dressage and show-jumping horses, particularly in the suspensory apparatus, including the distal sesamoidean ligaments. The findings of this study identify patterns of MCP/MTP abnormalities detected using standing MRI, with differences seen between forelimbs and hindlimbs and between different sports disciplines.

Cytotoxicity of local anaesthetics and protective effects of platelet rich plasma on equine tenocytes: An in vitro study.

Local anaesthetics (LAs) can have detrimental effects on rat, bovine, canine, and human tendon tissues and cells. Currently, there has been no available data on the impact of these drugs on equine tenocytes. Even if LA injection for managing painful tendon conditions in horses is limited, it is usually used via intra-articular, intrasynovial, perineural, and intrathecal as well as for lameness examinations. In this in vitro study, the cytotoxic effects of LAs, including lidocaine, mepivacaine, and bupivacaine on equine tenocytes, in the presence and absence of platelet rich plasma (PRP), were investigated. PRP accelerates tissue healing and can exert cytoprotective effects on different cell types exposed to different stressful conditions, including drugs. Results indicated that the exposure to LAs significantly reduced tenocytes viability in dose- and time-dependent manners while PRP was able to counteract their cytotoxic effects. Furthermore, microscopy and flow cytometry analyses revealed apoptosis and necrosis in equine tenocytes exposed to these drugs, that were both reduced when PRP was in the medium. These findings highlight the importance of considering the tenocyte toxicity associated with intrathecal and intraneural LA injections, as they might affect tenocytes or reduce the efficacy of associated therapies. Moreover, this study also highlights the protective effects of PRP, which could make LA injections safer.

Diagnostic characteristics of refractometry cut-off points for the estimation of immunoglobulin G concentration in mare colostrum.

BACKGROUND: Feeding foals with poor quality colostrum predisposes them to failure of passive transfer (FPT). FPT is a major risk factor for neonatal infections. OBJECTIVES: To assess the optimal cut-offs for the optical (OR) and digital (DR) refractometer and determine their accuracy for poor quality colostrum diagnosis. STUDY DESIGN: A diagnostic validation study. METHODS: Eighty-one colostrum samples and sera were collected from broodmares and their neonatal foals, respectively. Colostral and serum IgG concentrations were measured by radial immunodiffusion (RID), DR and OR. Correlation coefficients were calculated. ROC curves were generated to identify optimal cut-offs for the refractometers and their diagnostic characteristics were evaluated. RESULTS: The optimal cut-offs for DR and OR were ≤23.75% and 23.9%, respectively. The sensitivity and specificity of the DR were 93.3% (95% CI: 66.0-99.7) and 87.9% (95% CI: 77.0-94.3) to detect colostral IgG <60 g/L, respectively. The sensitivity and specificity of the OR were 93.3% (95% CI: 66.0-99.7) and 81.8% (95% CI: 70.0-89.9), respectively. DR and OR had negative predictive values of 98.3% (95% CI: 89.7-99.9) and 98.2% (95% CI: 89.0-99.9), respectively, whilst positive predictive values were lower. No maternal variable, including breed, significantly influenced colostral IgG concentrations. Fifteen out of 81 colostrum samples had IgG <60 g/L. FPT and PFPT were diagnosed in 4/81 and 10/81 foals, respectively. Nine out of 14 animals with FPT/PFPT suckled colostrum with IgG <60 g/L. A moderate correlation (rs 0.542; P = .01) was observed between IgG concentrations measured by RID in sera and colostrum. MAIN LIMITATIONS: A smaller number of samples than the size requirement based on a priori estimate of specificity and the low prevalence of poor quality colostrum. CONCLUSIONS: The method has the potential to reliably differentiate between good and poor quality colostrum. Assessing colostrum quality by refractometry may be an indicator of passive transfer of immunity.

INTRODUCTION/CONTEXTE: Nourrir les poulains avec du colostrum de mauvaise qualité prédispose à l'échec du transfert d'immunité passive (FPT). FPT constitue un risque majeur pour les infections néonatales. OBJECTIFS: Évaluer les valeurs limites optimales au réfractomètre optique (RO) et digital (RD) et déterminer leur précision pour le diagnostic du colostrum de pauvre qualité. TYPE D'ÉTUDE: Étude de validation diagnostique. MÉTHODES: Quatre-vingt-un colostrums et sérums ont été recueillis à partir de juments de reproduction et de leur poulains nouveaux-nés respectivement. Les concentrations d'IgG dans le sérum et le colostrum ont été mesurées par immunodiffusion radiale (IDR), RO et RD. Les coefficients de corrélation ont été calculés. Des graphes d'air sous la courbe (ASC) ont été générés afin d'identifier les valeurs limites optimales aux différents réfractomètres et leurs caractéristiques diagnostiques ont été évaluées. RÉSULTATS: Les valeurs limites optimales pour les RD et RO étaient ≤23.75% et 23.9% respectivement. La sensibilité et la spécificité du RD étaient 93.3% (95% IC: 66.0-99.7) et 87.9% (95% IC: 77.0-94.3) pour la détection des IgG colostraux <6000 mg/dl, respectivement. La sensibilité et spécificité du RO étaient de 93.3% (95% IC: 66.0-99.7) et 81.8% (95% IC: 70.0-89.9), respectivement. Les RD et RO avaient une valeur prédictive négative de 98.3% (95% IC: 89.7-99.9) et 98.2% (95% IC: 89.0-99.9) respectivement, alors que les valeurs prédictives positives étaient plus basses. Aucune variable maternelle, incluant la race, n'a influencé significativement les concentrations colostrales en IgG. Quinze des 81 échantillons colostraux avaient une valeur d'IgG <6000 mg/dl. FPT et PFPT ont été diagnostiqué chez 4/81 et 10/81 poulains respectivement. Neuf des 14 animaux avec FPT/PFPT ont reçu du colostrum ayant des valeurs d'IgG <6000 mg/dl. Une corrélation modérée (rs 0.542; p= 0.01) a été observée entre les concentrations d'IgG mesurées par IDR dans le sérum et le colostrum. LIMITES PRINCIPALES: Le nombre d'échantillon est inférieur à celui recommandé basé sur unestimé a priori de la spécificité et considérant la faible prévalence de colostrum de pauvre qualité. CONCLUSIONS: La méthodologie utilisée pourrait différencier de façon fiable les colostrums de pauvre et bonne qualité. L'évaluation de la qualité du colostrum par réfractométrie pourrait représenter un indice du transfert d'immunité passive.

Post-Mortem Computed Tomographic Features of the Most Caudal Lumbar Vertebrae, Anatomical Variations and Acquired Osseous Pathological Changes, in a Mixed Population of Horses.

The radiographic, ultrasonographic, and scintigraphic findings of horses with thoracolumbosacral pain have been previously reported. In this study, the computed tomographic appearance of anatomical variations and pathological changes of the equine caudal lumbar region through a post-mortem examination were investigated. A total of 40 horses that had died or were submitted for euthanasia, for reasons unrelated to the study, were included in the study. From all the specimens, the modified vertebral system was adopted to evaluate and describe the four most caudal lumbar vertebrae, which were numbered from a caudal reference point (lumbosacral junction), with the segment number designated within parentheses (i.e., L(i)-L(iv)). Contact of the spinous processes was detected in 21 specimens (54%) and fusion in 6 specimens (15%). Lumbar spondylosis was seen in 17 specimens (42.5%), more commonly on the lateral aspect or on both ventral and lateral aspects in 12 specimens (71%). The presence of spondylosis was found more commonly in older horses (p < 0.001). There was no difference in bony density in specimens with spondylosis or spinous processes contact compared to specimens without. The highest prevalence of bony changes was found at L(ii)-L(i) intertransverse joints in 28 specimens (97%) on the left and in 22 specimens (96%) on the right side. Spondylolisthesis and partial fusion of the L(ii)-L(i) vertebral disc were found in association with degenerative pathologies. This study showed a high frequency of several anatomical variations and acquired osseous pathological changes in the most caudal lumbar vertebrae via a CT examination.

Radiographic abnormalities of the thoracolumbar spinous processes do not differ between yearling and trained Thoroughbred horses without perceived back pain.

OBJECTIVE: The purpose of this prospective study was to investigate the prevalence and severity of radiographic abnormalities of the interspinous spaces (ISSs) in the thoracolumbar vertebral column of unbroken yearlings and to compare these findings with a group of older trained Thoroughbred horses without perceived back pain. ANIMALS: Yearlings (n = 47) and trained horses (55); 102 total. PROCEDURES: Each horse underwent a digital radiographic study of the thoracolumbar vertebral column (T7-L3) and each space graded for narrowing of the ISSs, increased opacity, radiolucency, and modeling of the cranial and caudal margins of 2 contiguous dorsal spinous processes (DSPs). This generated both an individual anatomical space score for each space and a total score for each horse for subsequent comparison. Statistical analysis of the results was then undertaken. RESULTS: Narrowing and impingement were detected in a third of the examined ISSs, while DSP increased opacity, radiolucencies, and modeling were found in over half of the yearlings. The median total score per horse was 33 (0 to 96) in the yearlings and 30 (0 to 101) in trained horses, indicating no significant difference in radiographic abnormalities (P = .91). Likewise, the median total score per anatomical space was 112 (25 to 259) and 127.5 (24 to 284) in the yearlings and trained horses (P = .83). No differences were found between the groups for number of radiographic abnormalities, scores, and total score. CLINICAL RELEVANCE: This study reported the incidence of DSP radiographic abnormalities in Thoroughbred horses. The absence of difference in occurrence between yearlings and older horses supported a developmental rather than acquired etiology.

Radiological Methods for the Imaging of Congenital Malformations of C6-T1, the First and Second Sternal Ribs and Development of a Classification System, Demonstrated in Warmblood Horses.

There are conflicting data in studies on malformations of the cervicothoracic (C-T) junction (C6 to T2, including the first and second ribs), but evidence is mounting that they can be of clinical significance for horses. The objectives of this study were to establish a radiographic protocol for imaging the C-T junction in the field and to classify the radiographic variations found in 39 warmblood horses presented for clinical evaluation due to behavioral or performance issues. Malformations of the ventral lamina of C6 and transposition onto the ventral aspect of C7 were seen in 37/39 (94.9%) horses for both conditions. Rib anomalies were found among the horses with C6 and C7 malformations. A missing first rib, unilateral or bilateral, was found in 3/35 (11.4%) horses, a unilateral shortening of the rib in 17/35 (48.6%) horses, a bilateral shortening of the ribs in 12/35 (34.3%) horses, bifid ribs in 3/35 (8.6%) horses, and only 4/35 (11.4%) horses had a normal length of the first rib on both sides. There was a moderately to highly significant association between the grades of left and right malformations of C6 and C7 and first ribs as well as between C6 and C7. A large number of malformations were visualized radiographically at the C-T junction using the newly described methods of latero-lateral and oblique radiographic projections, which allows for these features to be identified in living horses.

Post-mortem ultrasonographic and computed tomographic features of the anatomical variations and acquired pathological bony changes of the lumbosacroiliac region in a mixed population of horses.

BACKGROUND: Transrectal ultrasonography is the best technique for evaluating the ventral aspect of the lumbosacral and sacroiliac regions yet this diagnostic technique does not always lead to a final diagnosis of back pain in horses. OBJECTIVES: To describe anatomical variations and acquired pathological bony changes (APBCs) in the lumbosacral and sacroiliac regions detected by ultrasonography (US) and computed tomography (CT) examinations on specimens. We hypothesised that age, body mass, previous use and anatomical variations may be correlated with the presence and/or severity of APBCs. STUDY DESIGN: Descriptive cadaver study. METHODS: Lumbosacroiliac specimens were obtained from 51 horses that died or were euthanised for reasons other than the study and underwent US and CT examinations post-mortem. RESULTS: Forty-two specimens were analysed. The most prevalent lumbosacral disc morphology was type 2 (21/42), and protrusions were found in 15/42 specimens. Abnormal echogenicity of the L5-L6 and lumbosacral discs was detected in 11/42 and 30/42 specimens, respectively. Abnormalities in the size of the L5-L6 disc were found in 10/42 specimens and correlated with promontorium localisation (Cramér's V coefficient [V] = 0.42) and lumbosacral disc morphology (type 1: V = 0.41; type 5: V = 0.69). The most prevalent orientation of the L6 spinous process (SP) was convergent (24/42). The promontoria were mostly located between L6 and S1 (36/42). Lumbosacral spondylosis was detected in 24/42 specimens and spondylolisthesis in one. Age was associated with the severity of APBCs in the sacroiliac joints, lumbosacral intertransverse joints, articular process joints, spondylosis and L6 or S1 bone plate irregularities. Lumbosacral spondylosis or L6 extremitas caudalis irregularity was associated with lumbosacral angulation, variability in the size of the L5-L6 disc and localisation of the promontorium, L6 SP orientation and L6 extremitas caudalis irregularity with abnormal echogenicity of the LS disc. MAIN LIMITATIONS: Lack of information on clinical signs. CONCLUSIONS: High variability and prevalence of the anatomical variations and APBCs in the lumbosacroiliac region were observed, and correlations between some anatomical variations and APBCs and between APBCs and age were reported.

Bone stress injuries and fatigue fractures of the pelvis in endurance horses.

BACKGROUND: Bone stress injuries and fatigue fractures of the pelvis are reported in only a small number of endurance horses. OBJECTIVES: To describe bone stress injuries and fatigue fracture of the pelvis in endurance horses trained and competing on the deep sand surfaces. STUDY DESIGN: Retrospective case series. METHODS: Medical records of horses used for endurance and diagnosed with bone stress injuries and/or fatigue fractures of the pelvis by ultrasound were reviewed. The bone stress injuries and fatigue fractures were classified as affecting the iliac wing, the iliac shaft, the tuber ischiadicum, the rest of the ischium or the pubis and subdivided into four fracture configurations: isolated iliac fracture, isolated fracture of the floor of the pelvis, isolated tuber ischiadicum fracture and multiple fractures. Descriptive statistics were performed overall and on fracture configurations for age, sex, breed, level of activity, affected limbs, previous injuries, development of the injury, seasons in the UAE, physical and dynamic findings and outcome. For each fracture configuration and the outcome, multivariable logistic regression models were developed after univariable logistic regression and collinearity analyses. Significance was set at P ≤ .05. RESULTS: Sixty endurance horses were included; 48% (95% CI: 36%-61%) had isolated iliac fracture, 17% (7%-26%) isolated fracture of the floor of the pelvis, 15% (6%-24%) isolated tuber ischiadicum fracture and 20% (10%-30%) had multiple fractures. Breed (OR, 4.42; 95%CI, 1.02-19.57) was significantly associated with isolated iliac fracture and asymmetry of bone landmarks (OR, 7.42; 95% CI, 1.47-37.45) with isolated tuber ischiadicum fracture. Degree of lameness (OR, 3.08; 95% CI, 1.07-8.9) and trotting on three tracks (OR, 8.62; 95% CI, 1.43-51.9) were significantly associated with the diagnosis of isolated fracture of the floor of the pelvis. MAIN LIMITATIONS: Data acquired in a single country. CONCLUSIONS: Bone stress injuries and fatigue fractures of the pelvis can affect endurance horses trained and competing on deep sand. Isolated bone stress injuries and/or fatigue fractures of the ileum were the commonest followed by multiple pelvic bones involvement. The presence of lameness and trotting on three tracks suggest the presence of bone stress injuries and/or fatigue fractures of the floor of the pelvis; asymmetry of bony landmarks is more commonly detected in horses with bone stress injuries and/or fatigue fractures of the tuber ischiadicum.

Palliative repeated electroporations of oral tumours in dogs: A case series.

Electrochemotherapy (ECT) is a highly developed treatment for many solid tumours that provides good local control in 80% of neoplasms in dogs. ECT can be used to treat different types of tumours, particularly as an innovative approach for non-resectable masses. As reported in the literature, electroporation-based treatments are safe, simple, fast and cost-effective treatment alternatives for selected oral and maxillofacial tumours not involving the bone in dogs (e.g., small squamous cell carcinoma or malignant melanoma). In this descriptive retrospective paper, the authors describe the outcome of various types of oral tumours treated with ECT as a palliative first line treatment or as a rescue treatment in dogs with local tumour recurrence. Nineteen dogs were included and treated with at least one session of three electroporations coupled with intravenous administration of bleomycin every 21 days. Tumour size, localization, histotype, stage, recurrence, solid tumour response evaluation criteria (RECIST), local toxicity, progression free survival (PFS) and median survival time (MST) were evaluated. The small population did not allow the analysis of the ECT response by comparing different tumour types; further studies with a larger caseload are needed. However, all dogs, despite the low MST, showed a good local response to treatment with a rapid improvement in quality of life from the first ECT application; no side effects attributable to chemotherapy have been detected and toxicity due to the electroporation was minimal and well tolerated in all dogs.

Age and sex correlate with bony changes and anatomic variations of the lumbosacroiliac region of the vertebral column in a mixed population of horses.

OBJECTIVE: To provide a postmortem description of anatomic variations and changes of the lumbosacroiliac region in horses. The authors hypothesized that lesion severity would increase with age and body weight and correlate to anatomic variations. SAMPLES: Lumbosacroiliac vertebral specimens from 38 horses (mean age, 16 years; range, 5 to 30 years) that died or were euthanized for reasons unrelated to the study between November 2019 and October 2021. PROCEDURES: The lumbosacroiliac region of the vertebral column was removed from each cadaver. After dissection, disarticulation, and boiling, the anatomic specimens were examined for anatomic variations and osseous changes of the articular process joints (APJs), intertransverse joints (ITJs), and sacroiliac joints (SIJs). The lengths of L6-S1 intertransverse articular surfaces were measured and their ratios calculated. Descriptive statistics were obtained, and the χ2 test was used to assess differences in anatomic variations and abnormal changes of the APJs, ITJs, and SIJs. RESULTS: The most common anatomic variation was a sacrum-like shape of the transverse processes of L6 (29/38 [76%]) and converging orientation of dorsal spinous process of L6 (33/38 [87%]). The highest prevalence of bony changes was detected at L5-L6 (right, 34/38 [89%]; left, 33/38 [87%]) and L6-S1 APJs (right, 38/38 [100%]; left, 37/38 [97%]) and at SIJs (right, 32/38 [86%]; left, 31/38 [82%]). The shape of L6 transverse processes differed between breed (P = .01) and was associated with presence of L4-L5 ITJs (P < .01). CLINICAL RELEVANCE: Age and sex were associated with changes of the sacral dorsal spinous processes, ITJs, and APJs. The clinical significance of these findings could not be confirmed based on the study limitations.

Type, prevalence, and risk factors for the development of orthopedic injuries in endurance horses during training and competition.

OBJECTIVE: To report the type, prevalence, and risk factors for the development of orthopedic injuries in endurance horses. ANIMALS: 235 endurance horses. PROCEDURES: Medical records of horses examined between January 2007 and December 2018 were reviewed. Recorded data were birth; breed; sex; dates of first and last examinations; presence of any conformation fault, lameness, positive flexion test result, and orthopedic injury; starts in endurance competitions; level of athletic activity; professional status of trainer or rider; and whether an orthopedic injury developed in > 1 limb or during or within 2 days after competition, lameness resolved after treatment, reinjury occurred, horse was eliminated from competition after treatment, and the horse required retirement from endurance competitions. Anatomic locations of injuries were classified as proximal portion of the metacarpal area, midportion of the metacarpal area, metacarpo- or metatarsophalangeal (fetlock) area, tarsus, or foot. For each outcome, multivariable logistic regression models were developed after bivariable logistic regression and collinearity analyses. RESULTS: 351 orthopedic injuries were detected in 76.6% of the horses, with 27.1% that affected the fetlock area, 21.4% the proximal portion of the metacarpal area, 21.1% the foot, 12.8% the tarsus, 9.1% the midportion of the metacarpal area, and 8.5% other sites. High suspensory disease (21.4%) was the most common condition, followed by arthropathy of the metacarpo- or metatarsophalangeal joint (19.4%) and solar pain (14%). Age at first examination (OR, 1.70; 95% CI, 1.37 to 2.11), months of observation (OR, 1.03; 95% CI, 1.01 to 1.05), conformation fault of forelimbs (OR, 4.08; 95% CI, 1.53 to 10.89), and amateur status (OR, 2.62; 95% CI, 1.86 to 7.99) remained significant in the final multivariable regression model for the development of orthopedic injuries. CONCLUSIONS AND CLINICAL RELEVANCE: A large number of endurance horses developed ≥ 1 orthopedic injury during training or competition. Clinical and diagnostic examinations should be focused with particular attention to the metacarpophalangeal joints, proximal portion of the metacarpal area, and foot.

Multimodal Diagnostic Imaging to Identify Septic Apophysitis of the Proximal Humerus in a Thoroughbred Foal.

A 4-month-old Thoroughbred filly was referred for evaluation of severe left forelimb lameness of 24 hours duration. Radiographic projections of the shoulder revealed mild irregularity and sclerosis of the proximal humeral apophysis. Ultrasonographic examination showed a moderate increase in the amount of anechogenic synovial fluid within the intertubercular bursa and scapulohumeral joint, and irregularity of the ossifying bone surface of the intermediate tubercle of the humerus. Computed tomographic (CT) examination revealed a circular hypoattenuating area at the level of the proximal apophysis of the humerus. CT imaging in this case was essential for an early identification of the septic foci and it allowed ultrasound-guided sample from the lesion for the selection of targeted antibiotic therapy.

Adrenal Gland Ultrasonographic Measurements and Plasma Hormone Concentrations in Clinically Healthy Newborn Thoroughbred and Standardbred Foals.

Adrenal hormones, ACTH plasma concentrations and the ultrasonographic evaluation of the adrenal glands are considered complementary in clinical evaluations of the hypothalamic-pituitary-adrenal (HPA) axis function in several species. In dogs, age, size and weight have a significant effect on the ultrasonographic size of the adrenal glands. In neonatal foals, ultrasonographic evaluation and measurements of the adrenal glands have been demonstrated to be reliable; however, the effect of individual variables on ultrasonographic features has not been investigated, and the clinical usefulness of adrenal gland ultrasonography is still not known. The aims of this study were: (i) to provide and compare adrenal glands ultrasound measurements in healthy newborn Thoroughbred and Standardbred foals, and assess any effect of age, weight and sex on them; (ii) to assess and compare ACTH and steroid hormone concentrations in healthy neonatal foals of the two breeds. Venous blood samples and ultrasonographic images of the adrenal glands were collected from 10 healthy neonatal Thoroughbred and 10 healthy neonatal Standardbred foals. Ultrasonographic measurements of the adrenal glands were obtained and adrenocorticotropin (ACTH), cortisol, dehydroepiandrosterone (DHEA), progesterone (P4) and aldosterone plasma concentrations were assessed. The ACTH/cortisol, ACTH/progesterone, ACTH/aldosterone, ACTH/DHEA and cortisol/DHEA ratios were calculated. A significant positive correlation was found between the height of the right adrenal gland and the foal's weight; the width of the right and left adrenal gland and the medulla was significantly lower in Thoroughbreds than in Standardbreds. Cortisol and ACTH plasma concentrations were significantly higher and lower, respectively, in Thoroughbreds compared with Standardbreds. The cortisol/DHEA ratio was significantly higher in Thoroughbreds. This study provides reference ranges for neonatal Thoroughbred and Standardbred foals, and suggests the presence of breed-related differences in ultrasonographic adrenal gland measurements, plasmatic cortisol and ACTH concentrations. The higher cortisol/DHEA ratio detected in Thoroughbred foals could suggest a different response to environmental stimulation in the two breeds.

Circulating Transcriptional Profile Modulation in Response to Metabolic Unbalance Due to Long-Term Exercise in Equine Athletes: A Pilot Study.

Physical exercise has been associated with the modulation of micro RNAs (miRNAs), actively released in body fluids and recognized as accurate biomarkers. The aim of this study was to measure serum miRNA profiles in 18 horses taking part in endurance competitions, which represents a good model to test metabolic responses to moderate intensity prolonged efforts. Serum levels of miRNAs of eight horses that were eliminated due to metabolic unbalance (Non Performer-NP) were compared to those of 10 horses that finished an endurance competition in excellent metabolic condition (Performer-P). Circulating miRNA (ci-miRNA) profiles in serum were analyzed through sequencing, and differential gene expression analysis was assessed comparing NP versus P groups. Target and pathway analysis revealed the up regulation of a set of miRNAs (of mir-211 mir-451, mir-106b, mir-15b, mir-101-1, mir-18a, mir-20a) involved in the modulation of myogenesis, cardiac and skeletal muscle remodeling, angiogenesis, ventricular contractility, and in the regulation of gene expression. Our preliminary data open new scenarios in the definition of metabolic adaptations to the establishment of efficient training programs and the validation of athletes' elimination from competitions.