Playing with Low Amounts of Expanded Graphite for Melt-Processed Polyamide and Copolyester Nanocomposites to Achieve Control of Mechanical, Tribological, Thermal and Dielectric Properties.

Polyamide 11 (PA11) and copolyester (TPC-E) were compounded through melt extrusion with low levels (below 10%) of expanded graphite (EG), aiming at the manufacturing of a thermally and electrically conductive composite resistant to friction and with acceptable mechanical properties. Thermal characterisation showed that the EG presence had no influence on the onset degradation temperature or melting temperature. While the specific density of the produced composite materials increased linearly with increasing levels of EG, the tensile modulus and flexural modulus showed a significant increase already at the introduction of 1 wt% EG. However, the elongation at break decreased significantly for higher loadings, which is typical for composite materials. We observed the increase in the dielectric and thermal conductivity, and the dissipated power displayed a much larger increase where high frequencies (e.g., 10 GHz) were taken into account. The tribological results showed significant changes at 4 wt% for the PA11 composite and 6 wt% for the TPC-E composite. Morphological analysis of the wear surfaces indicated that the main wear mechanism changed from abrasive wear to adhesive wear, which contributes to the enhanced wear resistance of the developed materials. Overall, we manufactured new composite materials with enhanced dielectric properties and superior wear resistance while maintaining good processability, specifically upon using 4-6 wt% of EG.

Bayesian evaluation of sensitivity and specificity of blood culture media and hypoglycemia in sepsis-suspected calves.

BACKGROUND: Sepsis is a life-threatening condition for which critically important antimicrobials are often indicated. The value of blood culture for sepsis is indisputable, but appropriate guidelines on sampling and interpretation are currently lacking in cattle. OBJECTIVE: Compare the diagnostic accuracy of 2 blood culture media (pediatric plus [PP] and plus aerobic [PA]) and hypoglycemia for bacteremia detection. Estimate the contamination risk of blood cultures in critically ill calves. ANIMALS: One hundred twenty-six critically ill calves, 0 to 114 days. METHODS: Retrospective cross-sectional study in which the performance of PP, PA and hypoglycemia to diagnose sepsis was assessed using a Bayesian latent class model. A Cox proportional hazards model was used to compare time to positivity (TTP). Potential contamination was descriptively analyzed. Isolates were considered relevant when they were; member of the Enterobacterales, isolated from both blood cultures vials, or well-known, significant bovine pathogens. RESULTS: The sensitivities for PP, PA, and hypoglycemia were higher when excluding assumed contaminants; 68.7% (95% credibility interval = 30.5%-93.7%), 87.5% (47.0%-99.5%), and 61.3% (49.7%-72.4%), respectively. Specificity was estimated at 95.1% (82.2%-99.7%), 94.2% (80.7%-99.7%), and 72.4% (64.6%-79.6%), respectively. Out of 121 interpretable samples, 14.9% grew a presumed contaminant in PA, PP, or both. There was no significant difference in the TTP between PA and PP. CONCLUSIONS AND CLINICAL IMPORTANCE: PA and PP appear to outperform hypoglycemia as diagnostic tests for sepsis. PA seems most sensitive, but a larger sample size is required to verify this. Accuracy increased greatly after excluding assumed contaminants. The type of culture did not influence TTP or the contamination rate.

Clinical and imaging findings, treatment details and outcomes in foals with extensor tendon rupture-A multicentre retrospective study.

BACKGROUND: Forelimb extensor tendon rupture (ETR) in foals is sparsely documented. OBJECTIVES: To describe clinical and imaging findings, treatment details, and long-term outcome in foals with ETR. STUDY DESIGN: Multicentre retrospective case-series. METHODS: Clinical record review of foals with ETR, presented to Faculty of Veterinary Medicine at Ghent University (Belgium), the Clinic for Horses at the University of Veterinary Medicine Hannover (Germany), and Rossdales Equine Hospital (UK) between 2009-2021. Long-term outcome based on structured telephone interview with the owner at the university hospitals and on future ratings from a public racing results archive at Rossdales Equine Hospital. RESULTS: Eight foals (28%; 95%CI: 11.7%-44.3%) presented with ETR only, whereas 21 foals (72%; 95%CI: 55.7%-88.3%) presented with ETR and concurrent flexural limb deformity foals with ETR only were older (median 20 days; Interquartile range [IQR] 13-22) than foals with ETR and flexural limb deformity (median five days; IQR 3-11; p = 0.001). Treatment included medical support, immobilization, and box rest. Hospitalisation time was longer for foals with ETR and flexural limb deformity (median 26 days; IQR 16-44) than for ETR-only foals (median 11 days; IQR 6-16; p = 0.03). Total rehabilitation time was longer for foals with ETR and flexural limb deformity (median 58 days; IQR 42-91) than for foals without flexural limb deformity (median 32 days; IQR 12-39; p = 0.03). Six foals (21%; 95%CI: 6.3%-35.7%) were euthanased within seven months: three because of problems with limb protraction and progressive flexural limb deformity. Long-term follow-up (>18 months) was available for two cases with ETR only, and seven cases with ETR and flexural limb deformity. Both ETR-only foals had a positive cosmetic outcome but only one a positive functional outcome. Foals with ETR and concurrent flexural limb deformity suffered limitations regarding cosmetic appearance (5/7 negative) and limb function (7/7 negative). MAIN LIMITATIONS: Small sample size, retrospective study, and no clinical follow-up. CONCLUSIONS: ETR is a rare condition in this sample of foals treated under hospital conditions often requiring prolonged care, especially with concurrent flexural limb deformity. Further research should investigate potential associations with future athletic performance.

Assessing the functional properties of tenogenic primed mesenchymal stem cells in ex vivo equine tendon and ligament explants: A preliminary study.

Injuries to equine tendons and ligaments are career-compromising, causing reduced performance and premature retirement. Promising treatment alternatives have been investigated in the field of mesenchymal stem cells (MSCs). In this study, the tissue adherence and protein expression of tenogenic primed mesenchymal stem cells (tpMSCs) after administration to ex vivo tendon and ligament explants is investigated. First, collagen type I (COL I) and smooth muscle actin (SMA) expression was assessed in cytospins prepared from native MSCs and tpMSCs. Second, equine superficial digital flexor tendon and suspensory ligament explants were cultivated, and a lesion was treated with both cell types. Subsequently, cell adhesion to the explants and the amount of COL I and SMA positive cells was evaluated. The cytospins revealed a significantly higher COL I and lower SMA expression in tpMSCs compared to native MSCs. In the explants, tpMSCs showed a significantly higher tendon and ligament adherence. Furthermore, a significantly higher percentage of COL I positive and a lower percentage of SMA positive cells were observed in the lesions treated with tpMSCs. The results of these explant co-cultures may demonstrate at least a part of the mechanism of action and functional properties of tpMSCs in restoring function to tendons and ligaments.

Setting the Optimal Laser Power for Sustainable Powder Bed Fusion Processing of Elastomeric Polyesters: A Combined Experimental and Theoretical Study.

Additive manufacturing (AM) of polymeric materials offers many benefits, from rapid prototyping to the production of end-use material parts. Powder bed fusion (PBF), more specifically selective laser sintering (SLS), is a very promising AM technology. However, up until now, most SLS research has been directed toward polyamide powders. In addition, only basic models have been put forward that are less directed to the identification of the most suited operating conditions in a sustainable production context. In the present combined experimental and theoretical study, the impacts of several SLS processing parameters (e.g., laser power, part bed temperature, and layer thickness) are investigated for a thermoplastic elastomer polyester by means of colorimetric, morphological, physical, and mechanical analysis of the printed parts. It is shown that an optimal SLS processing window exists in which the printed polyester material presents a higher density and better mechanical properties as well as a low yellowing index, specifically upon using a laser power of 17-20 W. It is further highlighted that the current models are not accurate enough at predicting the laser power at which thermal degradation occurs. Updated and more fundamental equations are therefore proposed, and guidelines are formulated to better assess the laser power for degradation and the maximal temperature achieved during sintering. This is performed by employing the reflection and absorbance of the laser light and taking into account the particle size distribution of the powder material.

Genome-Wide Association Analyses of Osteochondrosis in Belgian Warmbloods Reveal Candidate Genes Associated With Chondrocyte Development.

Osteochondrosis (OC) is an important skeletal disease causing profound welfare concerns in horses. Although numerous studies have explored the genetics underlying OC in various breeds, the Belgian Warmblood (BW) remains unstudied despite having a concerning prevalence of 32.0%. As a result, this study aimed to conduct genome-wide association (GWA) analyses to identify candidate variants associated with OC in BWs. To achieve this, blood samples and radiographs were collected from 407 Belgian Warmbloods registered to one of two BW studbooks (Belgisch Warmbloedpaard and Zangersheide), and genotyping was performed using the 670K Axiom Equine Genotyping Array. GWA analyses using a principle component approach were then performed on OC status (OCS; presence or absence of OC at any joint), hock OC status (HOC) and stifle OC status (SOC). These analyses yielded significantly associated (P < .01) SNPs on Equus caballus chromosome (ECA) 3, ECA 12, and ECA 18 for OCS; however, no single nucleotide polymorphisms (SNPs) reached significance for HOC or SOC. Subsequent analysis of candidate genes within 500 kilobases of the significant SNPs revealed functions broadly related to cell differentiation and chondrocyte development. While this study represents another step forward in uncovering variants and biological pathways associated with OC, additional studies are needed to validate the newly identified candidate SNPs for OC in BWs. Further studies of OC in BWs, as well as other breeds, are critical in our efforts to fully understand the disease's etiopathogenesis and ultimately provide breeding programs better equipped to improve horse health and well-being.

The Evaluation of Equine Allogeneic Tenogenic Primed Mesenchymal Stem Cells in a Surgically Induced Superficial Digital Flexor Tendon Lesion Model.

Background: Tendon injuries are very common in horses and jeopardize the athletic performance, and due to the high risk of reinjury may lead to early retirement. The use of mesenchymal stem cells for the treatment of equine tendon disease is widely investigated because of their regenerative potential. The objective of this study is to investigate the safety and efficacy of equine allogeneic tenogenic primed mesenchymal stem cells (tpMSCs) for the management of tendinitis in horses. Methods: A core lesion was surgically induced in the superficial digital flexor tendon of both forelimbs of eight horses. After 7 days, one forelimb was treated with tpMSCs, while the contralateral forelimb served as an intra-individual control and was treated with saline. A prescribed exercise program was started. All horses underwent a daily clinical evaluation throughout the entire study period of 112 days. Blood samples were taken at different time points for hematological and biochemical analysis. Tendon assessment, lameness examination, ultrasound assessment and ultrasound tissue characterization (UTC) were performed at regular time intervals. At the end of the study period, the superficial digital flexor tendons were evaluated macroscopically and histologically. Results: No suspected or serious adverse events occurred during the entire study period. There was no difference in local effects including heat and pain to pressure between a single intralesional injection of allogeneic tpMSCs and a single intralesional injection with saline. A transient moderate local swelling was noted in the tpMSC treated limbs, which dissipated by day 11. Starting at a different time point depending on the parameter, a significant improvement was observed in the tpMSC treated limbs compared to the placebo for echogenicity score, fiber alignment score, anterior-posterior thickness of the tendon and echo type by UTC assessment. Immunohistochemistry 112 days post-injection revealed that the amount of collagen type I and Von Willebrand factor were significantly higher in the tendon tissue of the tpMSC group, while the amount of collagen type III and smooth muscle actin was significantly lower. Conclusion: Equine allogeneic tenogenic primed mesenchymal stem cells were shown to be well-tolerated and may be effective for the management of tendon injuries.

Cellular and Humoral Immunogenicity Investigation of Single and Repeated Allogeneic Tenogenic Primed Mesenchymal Stem Cell Treatments in Horses Suffering From Tendon Injuries.

The use of mesenchymal stem cells (MSCs) for the treatment of equine tendon disease is widely investigated because of their regenerative and immunomodulatory potential. However, questions have been raised concerning the immunogenic properties of allogeneic MSCs. Therefore, two studies were conducted to assess the safety of equine allogeneic peripheral blood-derived tenogenic primed MSCs (tpMSCs). The objective was to evaluate if a single and repeated tpMSC administration induced a cellular and humoral immune response in horses suffering from tendon injuries. Horses enrolled in the first study (n = 8) had a surgically induced superficial digital flexor tendon core lesion and were treated intralesionally with tpMSCs. Before and after treatment the cellular immunogenicity was assessed by modified mixed lymphocyte reactions. The humoral immune response was investigated using a crossmatch assay. Presence of anti-bovine serum albumin (BSA) antibodies was detected via ELISA. Horses enrolled in the second study (n = 6) suffered from a naturally occurring tendon injury and were treated twice with tpMSCs. Blood was collected after the second treatment for the same immunological assays. No cellular immune response was found in any of the horses. One out of eight horses in the first study and none of the horses in the second study had anti-tpMSC antibodies. This particular horse had an equine sarcoid and further investigation revealed presence of antibodies against sarcoid cells and epithelial-like stem cells before treatment, which increased after treatment. Additionally, formation of antibodies against BSA was observed. These findings might indicate a non-specific immune response generated after treatment. Serum from the other horses revealed no such antibody formation. These two studies showed that the administration of tpMSCs did not induce a cellular or humoral immune response following an intralesional single or repeated (two consecutive) allogeneic tpMSC treatment in horses with tendon injury, except for one horse. Therefore, a larger field study should confirm these findings and support the safe use of tpMSCs as a therapeutic for horses suffering from tendon injuries.

Evaluation of an osteochondral fragment-groove procedure for induction of metacarpophalangeal joint osteoarthritis in horses.

OBJECTIVE To evaluate lameness and morphological changes associated with an osteochondral fragment-groove procedure as a means of experimental induction of metacarpophalangeal (MCP) joint osteoarthritis within an 11-week period in horses. ANIMALS 6 nonlame adult warmbloods. PROCEDURES The right MCP joint of each horse underwent an osteochondral fragment-groove procedure (day 0). After 1 week of stall rest (ie, starting day 7), each horse was trained daily on a treadmill. Weekly, horses underwent visual and inertial sensor-based assessments of lameness. Both MCP joints were assessed radiographically on days 0 (before surgery), 1, 35, and 77. A synovial fluid sample was collected from the right MCP joint on days 0 (before surgery), 35, 36, 49, 63, and 77 for cytologic and biomarker analyses. On day 77, each horse was euthanized; both MCP joints were evaluated macroscopically and histologically. RESULTS Right forelimb lameness was detected visually and by the inertial sensor system when horses were moving on a straight line after distal forelimb flexion or circling left on days 14 to 77. Compared with presurgical values, synovial fluid interleukin-6, prostaglandin E2, hyaluronic acid, and interleukin-1 receptor antagonist protein concentrations were increased at 2 or 3 time points, whereas tumor necrosis factor-α and interleukin-10 concentrations were decreased at 1 time point. Gross examination of all right MCP joints revealed synovitis and wear lines; synovitis was confirmed histologically. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that a combined osteochondral fragment-groove procedure can be used to induce clinically and grossly observable early MCP joint osteoarthritis during an 11-week period in horses.

Incidence and risk factors of surgical site infection and septic arthritis after elective arthroscopy in horses.

OBJECTIVE: To determine the incidence of infection and associated risk factors, after elective arthroscopy. STUDY DESIGN: Retrospective case study. ANIMALS: Horses (n=1079) undergoing elective arthroscopy. METHODS: Medical records of all horses that underwent elective arthroscopy between 2006 and 2013 were reviewed. Age, gender, breed, surgeon, number of joints operated, total anesthetic time, perioperative antimicrobial administration, and the presence and size of osteochondral fragments/subchondral lesions were recorded. For each operated joint, the development of postoperative infection (surgical site infection [SSI] and/or septic arthritis) and long-term outcome (>6 months) were recorded. Multivariate logistic regression was used to test for association between the independent variables and the dependent outcomes. RESULTS: A total of 1741 joints in 1079 horses underwent arthroscopy. SSI without septic arthritis occurred in 1 fetlock joint (0.14%), 1 tibiotarsal joint (0.19%), and 6 femoropatellar joints (1.67%). Thirteen joints (0.75%) were diagnosed with septic arthritis, including 1 fetlock joint (0.14%), 4 tibiotarsal joints (0.74%), and 8 femoropatellar joints (2.23%). The probability of postoperative SSI was higher when large lesions (>40 mm long) were treated, compared to medium (20-40 mm, P = .005) and small (<20 mm, P < .001) lesions. SSI was a significant risk factor for the development of septic arthritis (P < .001). Although age did not affect the incidence of SSI, increasing age was associated with a lower rate of septic arthritis rate (P = .028). CONCLUSION: Septic arthritis after elective arthroscopy was more likely in the presence of SSI and younger age. Horses with large lesions were at risk for SSI, which translated into a higher incidence of postoperative septic arthritis after femoropatellar arthroscopy.

Agreement of manual cell counts and automated counts of the scil Vet abc Plus(+) hematology analyzer for analysis of equine synovial fluid.

The purpose of this study was to determine whether the scil Vet abc Plus(+) (SCIL Animal Care Company, Altorf, France), an impedance hematology analyzer, can accurately quantify and differentiate nucleated blood cells (NBCs) in equine synovial fluid. Synovial fluid samples (n=242) in different stages of experimentally induced inflammation were analyzed with and without hyaluronidase pretreatment and compared to manual hemocytometer counts and smear reviews. No significant effect of hyaluronidase pretreatment was observed. Total nucleated cell counts of the scil Vet abc Plus(+) were significantly higher compared to the manual method (P=0.02), yet the difference was small and clinically irrelevant (ratio manual/automated count equal to 0.97 with 95% CI [0.95, 1.00]). Differential cell counts of the scil Vet abc Plus(+) were not accurate. In conclusion, the scil Vet abc Plus(+) hematology analyzer is highly accurate for quantification, but not accurate for differentiation of NBCs in equine synovial fluid.

Long Term Outcome of Conservative Management or Surgical Treatment of Bovine Spastic Paresis: 79 Cases.

OBJECTIVE: To report the long term clinical outcome of calves treated surgically or managed conservatively for bovine spastic paresis of the gastrocnemius (BSP-G), quadriceps femoris muscle (BSP-Q), or mixed muscle involvement (BSP-M). STUDY DESIGN: Retrospective case study. ANIMALS: Calves (n = 79) with bovine spastic paresis. METHODS: Medical records of calves treated by partial tibial neurectomy or managed conservatively for bovine spastic paresis were analyzed for sex, breed, lineage history, and the onset, duration, and severity of clinical signs. Cases were classified as unilateral or bilateral BSP-G, BSP-Q, or BSP-M. Long term follow-up information was obtained by telephone questionnaire. RESULTS: The study group included 26 BSP-G (33%), 16 BSP-Q (20%), and 37 BSP-M (47%) calves. BSP-M and BSP-Q calves were significantly more bilaterally affected compared to BSP-G calves. Twenty-five of 26 BSP-G calves were treated surgically; 86% had complete resolution of clinical signs. Twenty-nine of 37 BSP-M calves were treated surgically; 81.5% improved, but none completely recovered. In all of the conservatively managed BSP-M calves, clinical signs gradually worsened. None of the BSP-Q calves were treated surgically; in 66.7%, clinical signs gradually worsened and 33.3% of calves spontaneously improved. CONCLUSION: Partial tibial neurectomy is advocated for the treatment of BSP-G and in selected cases of BSP-M. However, only partial resolution of clinical signs should be expected for BSP-M. No surgical treatment exists for BSP-Q calves, although spontaneous improvement is possible.

Bovine spastic paresis: current knowledge and scientific voids.

The aetiology, pathogenesis, diagnosis and treatment of bovine spastic paresis of the gastrocnemius muscle (BSP-G) have been investigated for several decades, but much remains to be elucidated. In some breeds, the proportion of atypical presentations of BSP involving the quadriceps muscle (BSP-Q) and/or several other muscles (mixed presentation, BSP-M) appears to be increasing. Differentiation between BSP-G, -Q and -M is challenging and existing surgical treatments are usually ineffective in cattle affected by one of the atypical forms of the disease. This paper reviews the current knowledge on BSP and addresses several areas where understanding of the disease is incomplete.

Does long-term unilateral circling affect locomotor symmetry in ponies used for carousel rides?

There is ethical debate on the use of ponies for carousel rides at city fairs, as these animals may develop progressive locomotor asymmetry during their career. To investigate this issue, 21 ponies used for carousel rides were walked and trotted over a pressure plate system. Non-directional symmetry ratios and directional asymmetry indices of forelimb peak vertical force (PVF), vertical impulse (VI), stance time (ST) and hoof contact area (CA) were calculated and compared to reference data. In both the carousel and reference groups, most ponies presented higher loading of the right forelimb at the walk and trot. Carousel ponies presented slightly, though significantly, lower symmetry ratios and more negative asymmetry indices than the reference group for PVF and VI, but not for ST and CA. However, repeated analysis after exclusion of the ponies with visually observed lameness revealed no significant differences in asymmetry indices, whereas symmetry ratios remained lower in the carousel group. Interestingly, Ten of 21 carousel ponies were subjectively more difficult to lunge on the circle opposite to their routine working direction, whereas the ponies in the reference group were easily lunged in both directions. In the absence of clear unilateral lameness or locomotor asymmetry in the majority of ponies, it is reasonable to assume a behavioural explanation for this observation. There was no significant association between the duration of the career and all symmetry indices. These results indicate an overall less symmetric locomotion in carousel ponies, but progressive locomotor asymmetry due to long-term unilateral circling seems to be unlikely.

Evaluation of three approaches for performing ultrasonography-guided anesthetic blockade of the femoral nerve in calves.

OBJECTIVE: To develop a practical ultrasonography-guided injection approach to anesthetic blockade of the femoral nerve in calves and to assess the method's accuracy. ANIMALS: 13 cadavers of 4-week-old male Holstein Friesian calves. PROCEDURES: Detailed topographic and anatomic cross-sectional evaluation of the relevant topography in 3 cadavers was performed to identify optimal injection approaches to the femoral nerve. Three approaches (ventral paravertebral, dorsal paravertebral, and ileal) were evaluated by simulated ultrasonography-guided perineural injection of methylene blue dye in 10 cadavers. Ultrasonographic image quality, number of needle redirections required for correct needle positioning, and injection success as defined through a 3-point grading system were recorded. RESULTS: The dorsal paravertebral approach yielded the best results, compared with the ileal and ventral paravertebral approaches, to properly and adequately stain the targeted nerve. CONCLUSIONS AND CLINICAL RELEVANCE: The dorsal paravertebral injection technique appeared to be the best choice for performing a femoral nerve block in calves, although this technique will need to be further evaluated in live calves to determine its effectiveness and clinical usefulness. Diagnostic perineural anesthesia of the femoral nerve in cattle might be helpful in identifying quadriceps muscle involvement in those with complex spastic paresis.

Contribution of dynamic calibration to the measurement accuracy of a pressure plate system throughout the stance phase in sound horses.

The aim of this study was to evaluate the accuracy of the vertical force curve of a pressure plate (PP) using dynamic calibration with a force plate (FP) in six sound Warmblood horses. The animals were walked and trotted over a combined PP-FP system sampling at 250 Hz. Five valid measurements of each forelimb were collected. The recalibration factor (RF), the ratio between the calibrated and raw PP data, was evaluated in each timeframe throughout the stance phase. Following dynamic calibration, the vertical force curve of the PP demonstrated a characteristic biphasic pattern at the walk and typical spikes at the beginning and end of stance at the trot. Both at walk and trot, the RF was considerably higher and more variable in the first 5% of stance (i.e. the impact phase) and during the final 20% of stance (i.e. the breakover phase), whereas between these phases (i.e. in the support phase), the RF was lower and remained relatively constant. These findings were confirmed by plotting the RF as a function of the vertical force and the RF in the loading part of the vertical force curve was lower than in the unloading part of the curve. Without dynamic calibration with a FP, the accuracy of the PP appears suboptimal, especially at the impact and breakover phases. However, the accuracy of the PP was relatively high and constant during the support phase, and higher loading was not associated with increasing deviation. It is therefore essential to optimise PP calibration, as this may downsize systematic measuring errors. However, in a clinical setting, where a stand-alone PP is used to objectively quantify locomotor symmetry, these errors can be readily eliminated by evaluating left:right symmetry ratios.

Viability and cell death of synovial fluid neutrophils as diagnostic biomarkers in equine infectious joint disease: a pilot study.

Synovial fluid samples from culture-confirmed infected joints (n=13), joints with pronounced non-infectious synovitis (n=11) and healthy joints (n=14) were collected from 24 equine patients and seven slaughterhouse horses. The samples from the joints with non-infectious synovitis and healthy joints served as negative controls. After isolation, counting and identification of neutrophils, the percentage viability, and the proportion apoptotic and necrotic neutrophils were determined by flow cytometry. Viability was significantly higher in infected samples compared to the controls. A significant difference in cell death type was observed, with apoptosis predominating in infected joints, and necrosis being more present in joints with pronounced non-infectious synovitis and healthy joints. The results of this pilot study suggest that flow cytometric analysis of neutrophil viability and cell death dynamics may assist the discrimination between infected and non-infected joints.

Flow cytometric detection of myeloperoxidase in horse neutrophils: a novel technique in equine diagnostic research.

Myeloperoxidase (MPO) is a protein of interest due to its involvement in equine pathologies. Until now, results in equine diagnostic research were achieved through extracellular MPO detection. However, studying the cellular MPO content in neutrophils has revealed important insights in human diseases. This study aimed to develop a technique for the specific detection of MPO on the single cell level defining a flow cytometric protocol for the detection of both equine surface-bound and cellular MPO. Both indirect and direct labeling techniques are described which include the comparison of two secondary antibodies and two linking-fluorochromes, respectively.

Accuracy of pressure plate kinetic asymmetry indices and their correlation with visual gait assessment scores in lame and nonlame dogs.

OBJECTIVE: To determine the accuracy of pressure plate kinetic asymmetry indices (ASIs) for diagnosis of unilateral hind limb lameness in dogs and their correlation with visual gait assessment (VGA) scores. ANIMALS: 9 healthy dogs and 16 dogs with previously diagnosed unilateral rupture of the cranial cruciate ligament and concurrent unilateral hind limb lameness. PROCEDURES: Dogs were walked over a pressure plate to determine paw contact area (PCA), peak vertical pressure (PVP), peak vertical force (PVF), and vertical impulse (VI) of both hind limbs. An ASI was calculated for each gait variable. Simultaneously, gait was assessed visually and scored by use of a numeric rating scale (0 to 10). The ASI of each variable was tested for its usefulness in discrimination between lame and nonlame dogs and for correlation with VGA scores. RESULTS: Sensitivity and specificity of ASIs to discriminate between lame and nonlame dogs were excellent for PVF, VI, and PCA; these values were substantially lower for ASI of PVP. Cutoff values to discriminate between lame and nonlame dogs were determined by use of ASIs for PVF, VI, and PCA; however, this could not be done for ASI of PVP. Correlations between ASIs of PVF, VI, and PCA and VGA scores were higher than correlation between the ASIs of PVP and VGA scores. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that ASIs of PVF and VI determined via analysis of pressure plate measurements were reliable indicators of clinical lameness in dogs, but the ASI of PVP was not. The ASI of PCA is an interesting new variable for assessment of limb loading symmetry.

Risk factors for incisional complications after exploratory celiotomy in horses: do skin staples increase the risk?

OBJECTIVE: To assess risk factors for celiotomy incisional infection in horses, especially the use of staples for skin closure. STUDY DESIGN: Case series. ANIMALS: Horses (n=356) that had 1 exploratory celiotomy for colic and survived >2 weeks after surgery between March 1, 2004 and December 31, 2007. METHODS: Incisions were classified as "normal" (no complication, only edema, serous drainage lasting <24 hours) or as "surgical site infection (SSI)" (persistent serosanguinous drainage or purulent drainage with or without positive bacterial culture). All possible risk factors, including method of skin closure (monofilament sutures or staples), were statistically analyzed using univariate and multivariate logistic regression. RESULTS: Of 356 horses, 303 (85%) had normal wound healing and 53 (15%) developed a SSI (purulent: 48 [14%]; persistent serosanguinous: 5 [1%]). Bacterial cultures were positive in 33 of 40 cases. Factors significantly associated with SSI in the multivariate analysis were: use of staples for skin closure (odds ratio [OR] 3.85, P<.001) and surgical site closure by a 1st or 2nd year resident (OR 2.20, P=.016). Lavage of the linea alba with sterile saline solution after closure was a protective factor (OR 0.38, P=.004). CONCLUSION: Use of staples for skin closure and less experienced surgeons closing the abdomen are risk factors for incisional infection. Incisional lavage after linea alba closure was a protective factor. CLINICAL RELEVANCE: Despite their ease and speed of application, skin staples can lead to an increase in celiotomy wound complications in horses.