Comparison of gluteus medius muscle activity in Haflinger and Noriker horses with polysaccharide storage myopathy.

Type 1 polysaccharide storage myopathy caused by genetic mutation in the glycogen synthase 1 gene is present in many breeds including the Noriker and Haflinger horses. In humans, EMG has already been used to document changes in the muscle activity patterns of patients affected by human glycogen storage disorders. Therefore, the aim of the present study was to describe gluteus muscle activity with surface electromyography (sEMG) in Haflinger and Noriker horses with known GYS1 mutation status during walk and trot. Thirty-two horses (11 Haflinger and 21 Noriker horses) with homozygous non-affected (GG), heterozygous affected (GA) and homozygous affected (AA) status of GYS1 mutation without overt clinical signs of any myopathy were selected for the current study. Using surface electromyography gluteus medius muscle activity at walk and at trot was measured, and muscle activity was described in relation to the maximum observed value at the same sensor and the same gait. In order to further describe the signals in detail comprising both frequencies and amplitudes, the crossings through the baseline and the 25, 50 and 75 percentile lines were determined. The result of the relative muscle activity did not show a consistent difference between affected and non-affected horses. Genetically affected (GA and AA) horses showed significantly less density of muscle activity for both gaits and horse breeds except for the crossings per second at the baseline and 75 percentile at walk in the Haflinger horses and 75 percentile at trot in the Noriker horses. The medians of all calculated density values were significantly lower in the GA Haflingers compared to the GG Haflingers (p = 0.012) and also in the AA Norikers compared to the GG Norikers (p = 0.011). Results indicate that the GYS1 mutation reduces the number of functional muscle fibres detected by sEMG measurements even in the absence of overt clinical signs.

Equine Hoof Canker: Bovine Papillomavirus Infection Is Not Associated With Impaired Keratinocyte Differentiation.

Impaired keratinocyte differentiation has recently been suggested as a key event in equine hoof canker development. Koilocytotic appearance of keratinocytes, one of the most characteristic morphological alterations in hoof canker tissue, is also a common marker for papillomavirus (PV) infection, and bovine PV-1 and/or -2 (BPV-1/2) has previously been detected in equine canker patients. Therefore, the present study aimed to correlate the frequency and severity of koilocytotic keratinocytes with BPV detection in hoof canker samples. Hoof tissue of 5/18 canker-affected horses and 2/6 control horses tested positive for BPV-1/2 DNA using polymerase chain reaction. Thus, no association between the presence of BPV-1/2 papillomaviral DNA and koilocytotic appearance was found. Proteins associated with but not specific for PV infection were also investigated. Using immunohistochemistry, specific adhesion molecules (E-cadherin and ß-catenin) and intermediate filaments (keratins 6 and 14) important for intact epidermal barrier function and keratinocyte differentiation were documented in control samples (n = 6) and in hoof canker tissue samples (n = 19). Altered expression patterns of intermediate filaments and adhesion molecules were demonstrated in canker tissue, confirming the importance of incomplete keratinocyte differentiation, as well as the crucial role of keratinocyte differentiation in hoof canker.

Use of Physical Self-Experience for Teaching Lameness Evaluation: Short-Term Effects on Lameness Evaluation of Horses with Mild Forelimb Lameness by Novice Veterinary Students.

Lameness evaluation (LE) is an important veterinary skill, but it can be a challenging task to teach. Acoustic and visual input in conjunction with acting are the three major learning channels for acquiring new information. Acting (e.g., physical self-experience) has not been reported as a didactic tool for LE; therefore, we investigated two physical self-experience techniques, imitation of lameness during LE instruction and head nod during LE. Undergraduate veterinary students (N = 78) who had not yet received any instructions for LE underwent standard instruction for LE, followed by instructions to head nod, instructions to imitate lameness, or neither. Students' subjective LE skills were then tested against those of senior clinicians on two horses that were either sound or mildly forelimb lame. In more than 80%, there was agreement on the presence or absence of lameness independent of instruction, and we found no significant evaluation differences between didactic strategies. Specific instructions for head nodding did not significantly influence the quality of LE, possibly because head nodding was widespread even when no specific instructions had been given. Veterinary students who had been taught to imitate lameness without instructions to head nod were consistently closest to the assessment of the senior clinicians, and in walk these students were significantly better at LE than students additionally instructed to head nod. This finding indicates that imitation of lameness, but not necessarily head nodding, may be beneficial for understanding body movement such as mild equine forelimb lameness.

Establishment of a model for equine small intestinal disease: effects of extracorporeal blood perfusion of equine ileum on metabolic variables and histological morphology - an experimental ex vivo study.

BACKGROUND: In horses a number of small intestinal diseases is potentially life threatening. Among them are Equine Grass Sickness (EGS), which is characterised by enteric neurodegeneration of unknown aetiology, as well as reperfusion injury of ischaemic intestine (I/R), and post-operative ileus (POI), common after colic surgery. The perfusion of isolated organs is successfully used to minimize animal testing for the study of pathophysiology in other scenarios. However, extracorporeal perfusion of equine ileum sourced from horses slaughtered for meat production has not yet been described. Therefore the present study evaluated the potential of such a model for the investigation of small intestinal diseases in an ex vivo and cost-efficient system avoiding experiments in live animals. RESULT: Nine ileum specimens were sourced from horses aged 1-10 years after routine slaughter at a commercial abattoir. Ileum perfusion with oxygenated autologous blood and plasma was successfully performed for 4 h in a warm isotonic bath (37.0-37.5 °C). Ileum specimens had good motility and overall pink to red mucosa throughout the experiment; blood parameters indicated good tissue vitality: 82 ± 34 mmHg mean arterial partial pressure of oxygen (pO2) compared to 50 ± 17 mmHg mean venous pO2, 48 ± 10 mmHg mean arterial partial pressure of carbon dioxide (pCO2) compared to 66 ± 7 mmHg venous pCO2 and 9.8 ± 2.8 mmol/L mean arterial lactate compared to 11.6 ± 2.7 mmol/L venous lactate. There was a mild increase in ileum mass reaching 105 ± 7.5% of the pre-perfusion mass after 4 hours. Histology of haematoxylin and eosin stained biopsy samples taken at the end of perfusion showed on average 99% (±1%) histologically normal neurons in the submucosal plexus and 76.1% (±23.9%) histologically normal neurons in the myenteric plexus and were not significantly different to control biopsies. CONCLUSION: Extracorporeal, normothermic perfusion of equine ileum over 4 h using autologous oxygenated blood/plasma perfusate showed potential as experimental model to test whether haematogenous or intestinal exposure to neurotoxins suspected in the pathogenesis of EGS can induce neuronal damage typical for EGS. Also, this model may allow investigations into the effect of pharmaceuticals on I/R injury, as well as into the pathogenesis of equine POI.

Long term consistency and location specificity of equine gluteus medius muscle activity during locomotion on the treadmill.

BACKGROUND: The equine m. gluteus medius (GM) is the largest muscle of the horse, its main movement function is the extension of the hip joint. The objective of the present study was to measure equine GM activity in three adjacent locations on GM during walk and trot on a treadmill, in order to document potential differences. Fourteen Haflinger mares were measured using surface electromyography and kinematic markers to identify the motion cycles on three occasions over 16 weeks. The electrodes were placed on left and right gluteus medius muscle over the middle of its widest part and 5 cm lateral and medial of it. For data processing, electrical activity was normalised to its maximum value and timing was normalised to the motion cycle. A Gaussian distribution approach was used to determine up to 10 modes of focussed activity, and results were analysed separately for stance and swing phase of the ipsilateral hindlimb. RESULTS: Fair reliability was found for mean mode values (Cronbach's alpha = 0.66) and good reliability was found for mean mode locations (Cronbach's alpha = 0.71) over the three data collection days. The magnitude of muscle activity identified as mean mode value was much larger at trot than at walk, and mean mode value was significantly different between stance phases of walk and trot for all electrode positions (p < 0.01). The pattern of muscle activity identified as mean mode location was significantly different for walk and trot at all electrode positions, both during stance and swing phases (p < 0.001). This indicates the different timing pattern between the gaits. Results of the three electrode positions on the same muscle during each gait were not significantly different when comparing the same measurement. CONCLUSIONS: The middle of the equine GM does not show any indication of functional differentiation during walk and trot on a treadmill; this might be due to lack of segmentation as such, or due to lack of need for segmented use for these very basic main tasks of the muscle. The reliability of the sEMG measurements over several weeks was fair to good, an indication for the robustness of the methodology.

Algometry to measure pain threshold in the horse's back - An in vivo and in vitro study.

BACKGROUND: The aim of this study was to provide information on algometric transmission of pressure through the dorsal thoracolumbar tissues of the equine back. Using a commercially available algometer, measurements were carried out with six different tips (hemispheric and cylindrical surfaces, contact areas 0.5 cm2, 1 cm2, and 2 cm2). In nine live horses the threshold of pressure that lead to any reaction was documented. In postmortem specimens of five euthanized horses the transmission of algometer pressure onto a pressure sensor placed underneath the dorsal thoracolumbar tissues at the level of the ribs or the transverse lumbar processes respectively was measured. RESULTS: Algometer tips with a contact area of 1 cm2 led to widely similar results irrespective of the surface shape; these measurements also had the lowest variance. Contact areas of 0.5 cm2 resulted in a lower pressure threshold, and those of 2 cm2 resulted in a higher pressure threshold. The hemispheric shape of the contact area resulted in a higher pressure threshold, than the cylindrical contact area. Compared to the thoracic region, a significantly higher pressure threshold was found in the lumbar region in the live horses. This result corresponds to the increased tissue thickness in the lumbar region compared to the thoracic region, also documented as less pressure transmission in the lumbar region on the in vitro specimens. CONCLUSIONS: Algometry is an easily practicable and well tolerated method to quantify pain but it is important to consider the many factors influencing the results obtained.

Course of serum amyloid A (SAA) plasma concentrations in horses undergoing surgery for injuries penetrating synovial structures, an observational clinical study.

BACKGROUND: Injuries penetrating synovial structures are common in equine practice and often result in septic synovitis. Significantly increased plasma levels of serum amyloid A (SAA) have been found in various infectious conditions in horses including wounds and septic arthritis. Plasma SAA levels were found to decrease rapidly once the infectious stimulus was eliminated. The purpose of the current study was to investigate the usefulness of serial measurements of plasma SAA as a monitoring tool for the response to treatment of horses presented with injuries penetrating synovial structures. In the current study plasma SAA concentrations were measured every 48 hours (h) during the course of treatment. RESULTS: A total of 19 horses with a wound penetrating a synovial structure were included in the current study. Horses in Group 1 (n = 12) (injuries older than 24 h) only needed one surgical intervention. Patients in this group had significantly lower median plasma SAA levels (P = 0.001) between 48 h (median 776 mg/L) and 96 h (median 202 mg/L) after surgery. A significant decrease (P = 0.004) in plasma SAA levels was also observed between 96 h after surgery (median 270 mg/L) and 6 days (d) after surgery (median 3 mg/L). Four horses (Group 2) required more than one surgical intervention. In contrast to Group 1 patients in Group 2 had either very high initial plasma concentrations (3378 mg/L), an increase or persistently high concentrations of plasma SAA after the first surgery (median 2525 mg/L). A small group of patients (n = 3) (Group 3) were admitted less than 24 h after sustaining a wound. In this group low SAA values at admission (median 23 mg/L) and peak concentrations at 48 h after surgery (median 1016 mg/L) were observed followed by a decrease in plasma SAA concentration over time. CONCLUSIONS: A decrease in plasma SAA concentrations between two consecutive time points could be associated with positive response to treatment in the current study. Therefore, serial measurements of plasma SAA could potentially be used as an additional inexpensive, quick and easy tool for monitoring the treatment response in otherwise healthy horses presented with injuries penetrating synovial structures. However further studies will be necessary to ascertain its clinical utility.

Carriage of meticillin-resistant staphylococci between humans and animals on a small farm.

BACKGROUND: Meticillin-resistant staphylococci (MRS) are pathogens of increasing importance to human and animal health worldwide. Transmission of meticillin-resistant Staphylococcus aureus (MRSA) between animals and humans has been well documented. By contrast, information about transmission of other Staphylococcus spp. is limited. HYPOTHESIS/OBJECTIVES: The aim of this study was to screen animals and humans on a small farm for nasal carriage of MRS and to assess interspecies exchange. METHODS: After detection of MRSA in a lung sample of a deceased cat, which lived on a small mixed farm, nasal swabs were taken within two weeks, four and 16 months from other animals of various species and humans living on the farm. Swabs were cultured for MRS which were then characterized molecularly. RESULTS: MRSA and meticillin-resistant coagulase negative staphylococci (MRCoNS), including Staphylococcus haemolyticus, S. epidermidis and S. fleurettii, were isolated from humans and different animal species. Typing of the MRS revealed isolates with the same characteristics in different human and animal hosts. CONCLUSIONS AND CLINICAL IMPORTANCE: To the best of the authors' knowledge, this is the first report of carriage of both MRSA and MRCoNS among humans and various animals within a shared environment. The detection of strains with indistinguishable molecular characteristics strongly suggested transmission of these MRS between the various animal species and humans.

MRI-determined lumbar muscle morphometry in man and sheep: potential biomechanical implications for ovine model to human spine translation.

The sheep is a commonly used animal model for human lumbar spine surgery, but only in vitro investigations comparing the human and ovine spine exist. Spinal musculature has previously not been compared between man and sheep. This additional knowledge could further indicate to what extent these species are biomechanically similar. Therefore, the purpose of the study was to investigate spinal muscle morphometric properties using magnetic resonance imaging (MRI) in different age groups of healthy human participants and sheep in vivo. Healthy human participants (n = 24) and sheep (n = 17) of different age groups underwent T1-weighted MRI of the lumbar spine. Regions of interest of the muscles erector spinae (ES), multifidus (M) and psoas (PS) were identified. The ratio of flexor to extensor volume, ratio of M to ES volume, and muscle fat relative to an area of intermuscular fat were calculated. Sheep M to ES ratio was significantly smaller than in the human participants (sheep 0.16 ±â€…0.02; human 0.37 ±â€…0.05; P < 0.001), although flexor to extensor ratio was not significantly different between species (human 0.39 ±â€…0.08; sheep 0.43 ±â€…0.05; P = 0.06). Age did not influence any muscle ratio outcome. Sheep had significantly greater extensor muscle fat compared with the human participants (M left human 40.64%, sheep 53.81%; M right human 39.17%, sheep 51.33%; ES left human 40.86%, sheep 51.29%; ES right human 35.93%, sheep 44.38%; all median values; all P < 0.001), although PS did not show any significant between-species differences (PS left human 36.89%, sheep 33.67%; PS right human 32.78%, sheep 30.09%; P < 0.05). The apparent differences in the size and shape of sheep and human lumbar spine muscles may indicate dissimilar biomechanical and functional demands, which is an important consideration when translating to human surgical models.

Radiological features of arterial channels in the equine third phalanx measured using a novel customized software represent changes of laminitis.

OBJECTIVE: To identify and measure radiolucencies at the solear margin of the distal phalanx in radiographs of healthy and laminitic hooves. SAMPLE: Clinical records and dorsoproximal-palmarodistal radiographs of equine forelimbs with radiological diagnoses of either laminitis (n = 40, L) or navicular syndrome (n = 40, NS). METHODS: Outlines of the radiolucent structures at the solar margin were drawn in ImageJ, and a customized novel plugin "Arteries Analyzer/ImageJ" was used for measurements. The diverging radiolucencies outside the terminal arc of the distal phalanx were differentiated as arterial channels (open at the solear margin) and ellipses (closed at the solear margin). Comparisons between L and NS, between distal phalanges with and without ellipses, and of arterial channels and ellipses in areas were compared using Wilcoxon and the Mann-Whitney U tests, respectively. The reliability and repeatability of the method were tested using Friedman's test. RESULTS: Fewer arterial channels but more ellipses were identified in L than in NS. In phalanges with ellipses (n = 47), the number of ellipses and the number of arterial channels were negatively correlated (PCC -0.181, P = .224). The number of ellipses correlated positively with the severity of laminitis (PCC 0.495, P < .001; n = 80) and with the degree of rotation of the distal phalanx (PCC 0.392, P < .001; n = 80). CLINICAL RELEVANCE: The software tool successfully measured arterial channels and ellipses outlined by the evaluators. Results indicate that healthy arteries develop into pathological ellipses in laminitic feet. This may be used to complement the interpretation of radiographs and support clinical decision-making.

The assessment of paraspinal muscle epimuscular fat in participants with and without low back pain: A case-control study.

It remains unclear whether paraspinal muscle fatty infiltration in low back pain (LBP) is i) solely intramuscular, ii) is lying outside the epimysium between the muscle and fascial plane (epimuscular) or iii) or combination of both, as imaging studies often use different segmentation protocols that are not thoroughly described. Epimuscular fat possibly disturbs force generation of paraspinal muscles, but is seldomly explored. This project aimed to 1) compare epimuscular fat in participants with and without chronic LBP, and 2) determine whether epimuscular fat is different across lumbar spinal levels and associated with BMI, age, sex and LBP status, duration or intensity. Fat and water lumbosacral MRIs of 50 chronic LBP participants and 41 healthy controls were used. The presence and extent of epimuscular fat for the paraspinal muscle group (erector spinae and multifidus) was assessed using a qualitative score (0-5 scale; 0 = no epimuscular fat and 5 = epimuscular fat present along the entire muscle) and quantitative manual segmentation method. Chi-squared tests evaluated associations between qualitative epimuscular fat ratings and LBP status at each lumbar level. Bivariate and partial spearman's rho correlation assessed relationships between quantitative and qualitative epimuscular fat with participants' characteristics. Epimuscular fat was more frequent at the L4-L5 (X2 = 13.781, p = 0.017) and L5-S1 level (X2 = 27.825, p < 0.001) in participants with LBP compared to controls, which was not found for the higher lumbar levels. The total qualitative score (combined from all levels) showed a significant positive correlation with BMI, age, sex (female) and LBP status (r = 0.23-0.55; p < 0.05). Similarly, the total area of epimuscular fat (quantitative measure) was significantly correlated with BMI, age and LBP status (r = 0.26-0.57; p < 0.05). No correlations were found between epimuscular fat and LBP duration or intensity. Paraspinal muscle epimuscular fat is more common in chronic LBP patients. The functional implications of epimuscular fat should be further explored.

Health Promotion for Students of Veterinary Medicine: A Preliminary Study on Active Microbreaks and Ergonomics Education.

Occupational hazards, such as psychosocial stressors, physical injuries from human-animal interactions, and physically demanding work tasks, are common in the veterinary profession, and musculoskeletal discomfort and pain (MDP) may already be present in veterinary undergraduates. This preliminary study investigates the effects of very short, active interventions, called microbreaks, in 36 veterinary students. At the start, participants had a high prevalence of MDP, especially in the neck and lower back. Within a 12-week observational period, 6 weeks of active intervention comprised teaching microbreaks (nine strengthening, stretching, and relaxation exercises; 30-90 s each) and a weekly veterinary-specific ergonomics education and discussion. After the intervention, participants reported fewer painful body regions and an increase in their self-efficacy in potentially painful, risky, or dangerous human-animal interactions. After the 12-week observational period, participants had increased self-efficacy in the maintenance of physical health and self-protection but decreased self-efficacy in healing injuries after veterinary human-animal interactions. Participants felt to have increased and decreased control over dangerous situations with dogs and horses, respectively, although self-efficacy in handling horses increased. Participants integrated microbreaks well into their undergraduate activities and rated the topic relevant to their (later) profession. This should encourage the inclusion of similar programs in undergraduate curricula.

The clinical presentation and surgical treatment of verrucous dermatitis lesions in a draught horse.

Verrucous pastern dermatitis is a progressive inflammatory skin disease commonly involving the palmar or plantar aspects of the pasterns of horses. There are no reports of successful surgical treatment for multifocal circumscribed verrucous masses in the chronic stages of verrucous pastern dermatitis. A combination of sharp dissection and electrocautery was used to resect numerous multifocal circumscribed verrucous masses from the distal hindlimb of an 11-year-old gelding draught horse. There was no evidence of significant regrowth or complications at a 24 month postoperative examination.

Partial ostectomy of the dens to correct atlantoaxial subluxation in a pony.

OBJECTIVE: To report a surgical technique that allows decompression and anatomic re-alignment for management of subluxation of the atlantoaxial articulation. STUDY DESIGN: Clinical report. ANIMALS: Four-year-old Welsh Section B pony gelding. METHODS: Attempts at closed reduction of subluxation of the atlantoaxial articulation under general anesthesia were unsuccessful, so a ventral surgical approach allowing partial ostectomy of the dens of the axis was used to facilitate reduction. RESULT: Recovery from surgery was uneventful and the pony remained comfortable without neurologic deficits. Both neck stiffness and ataxia resolved. Radiographic examination at 5 days and 6 months postoperatively showed normal anatomic position of the dens of the axis and stabilization of the atlantoaxial joint. CONCLUSION: Partial ostectomy of the dens using a ventral approach can be used to facilitate reduction of atlantoaxial subluxation.

Differentiation of ataxic and orthopedic gait abnormalities in the horse.

The differentiation of ataxia and orthopedic disease can be facilitated by the use of several additional tests, not commonly part of either neurologic or orthopedic examination protocols. However, a full neurologic and orthopedic examination and suitable diagnostic imaging will of course also be necessary in such cases. The common association of orthopedic and neurologic disease makes it even more necessary to correctly attribute movement or posture abnormalities to potentially treatable structures.

Endotoxin-induced changes in expression of cyclooxygenase isoforms in the lamellar tissue of extracorporeally haemoperfused equine limbs.

Angiogenesis and sepsis-related equine laminitis have several features in common. Both events can be induced by endotoxin (lipopolysaccharide- LPS) and both are associated with increased expression of the enzyme cyclooxygenase (COX), of which two isoforms (COX-1 and COX-2) exist. To examine the causal relationship between LPS exposure and COX expression and to investigate the tissue distribution of COX in the LPS-exposed tissue, the technique of extracorporeal haemoperfusion of isolated equine forelimbs was utilized. Perfusion was performed for 10 hr under physiological conditions (control-perfused limbs, n = 5) and with addition of 80 ng/L of endotoxin (LPS-perfused limbs; n = 5). After perfusion, samples of lamellar tissue were collected from the dorsal aspect of the hoof wall. Additional control samples were collected from three non-perfused limbs. Immunohistochemical analysis was performed using antibodies against COX-1 and COX-2, and intensity of immunohistochemical staining was scored for each isoform. In the lamellar tissue of control- and LPS-perfused limbs, there was no significant difference in COX-1 staining intensity and distribution, whereas COX-2 expression was significantly increased in LPS-perfused limbs (especially in endothelial cells, fibroblasts and intravasal leucocytes as well as in epidermal basal cells at the base of the primary epidermal lamellae). These results suggest that COX-2 and its metabolites are involved in the initiation of pathological changes seen in sepsis-associated events such as sepsis-related laminitis. In such cases, COX-2 could therefore be an important therapeutic target; however, early therapy may be required as increase in COX-2 expression occurs within 10 hr after LPS exposure.

Movement Caused by Electrical Stimulation of the Lumbosacral Region in Standing Horses.

Electrical stimulation is commonly used as a modality for physical therapy in human and veterinary medicine. However, studies measuring the movement generated by electrical stimulation in horses are rare. The present study therefore evaluates the range of movement provoked by a commercially available physical therapy unit (FES310) and contrasts it with the movement generated by manually induced pelvic inclination (back rounding). Ten horses were tested on three measurement days over one week. Electrical stimulation was applied via a back treatment pad (belonging to the FES310 system) containing six electrodes (three on either side of the spine) placed over the lumbosacral region. This system produced a pulsed, biphasic electrical stimulation in a rectangular waveform which was gradually increased to a maximum of 10 volts. Before and after electrical stimulation testing, manual pelvic inclination was achieved by pressure on two points lateral to the root of the tail. Muscle tone and lameness were evaluated before and after treatments. Skinfold thickness, body condition score, and body mass were measured to detect possible confounding factors. Using kinematics, the angle ranges during movement of ten three-dimensional angles of the trunk, the pelvis, and the hind limbs were further analyzed. Movement was produced with manual stimulation in every tested individual on all measurement days and with electrical stimulation on at least one measurement day. The electrical stimulation led to significantly (P < .05) smaller angle ranges which were 15 %-57 % of the median of the manually stimulated movement. Strong positive correlations between angle ranges of the electrically generated movement were found for the hind limbs implicating their involvement in the movement created. Correlations between skinfold thickness, body condition score, and body mass with the angle ranges were weak and not significant. Before and after electrical and manual stimulation, muscle tone and lameness were similar. In the present study, both electrical and manual stimulation were proven to produce significant trunk and hind limb movement. Within this study's electrical stimulation treatment protocol, the movement generated by electrical stimulation was significantly less than the movement caused by manual pelvic inclination. However, electrical stimulation could easily be applied over a longer period and in a higher frequency than it would be possible for manual pelvic inclination. This treatment shows potential for stabilization and or mobilization of the lumbosacral region, although its efficiency as a therapeutic tool and its effect on specific orthopedic problems and is to be evaluated in further research.

Broad-Spectrum Cephalosporin-Resistant Klebsiella spp. Isolated from Diseased Horses in Austria.

The aim of the present study was to investigate the diversity of broad-spectrum cephalosporin-resistant Klebsiella spp. isolated from horses in Austria that originated from diseased horses. A total of seven non-repetitive cefotaxime-resistant Klebsiella sp. isolates were obtained during diagnostic activities from autumn 2012 to October 2019. Antimicrobial susceptibility testing was performed. The isolates were genotyped by whole-genome sequencing (WGS). Four out of seven Klebsiella isolates were identified as K. pneumoniae, two as K. michiganensis and one as K. oxytoca. All isolates displayed a multi-drug resistant phenotype. The detection of resistance genes reflected well the phenotypic resistance profiles of the respective isolates. All but one isolate displayed the extended-spectrum ß-lactamases (ESBL) phenotype and carried CTX-M cefotaximases, whereas one isolate displayed an ESBL and AmpC phenotype and carried cephamycinase (CMY)-2 and sulfhydryl variable (SHV)-type b and Temoniera (TEM) ß-lactamases. Among Klebsiella pneumoniae isolates, for different sequence types (ST) could be detected (ST147, ST307, ST1228, and a new ST4848). Besides resistance genes, a variety of virulence genes, including genes coding for yersiniabactin were detected. Considering the high proximity between horses and humans, our results undoubtedly identified a public health issue. This deserves to be also monitored in the years to come.

Effects of long-term extracorporeal blood perfusion of the distal portion of isolated equine forelimbs on metabolic variables and morphology of laminar tissue.

OBJECTIVE: To establish an ex vivo model of blood perfusion in the distal portion of isolated equine forelimbs that closely represents the in vivo situation in the laminar tissue of the hoof. SAMPLE POPULATION: 18 forelimbs collected from 9 healthy adult horses following slaughter at a licensed abattoir. PROCEDURES: The distal portion of isolated equine forelimbs from 9 horses were perfused under physiologic conditions over a period of 6, 8, and 10 hours with autologous blood. To determine cell viability in perfused tissues, indicators for metabolism (lactate generation and glucose and oxygen consumption) as well as indicators for cell damage (potassium concentration and lactate dehydrogenase activity) were examined at 1-hour intervals from samples of the perfusate. Weight gain in the forelimb was used to determine the edema index. After perfusion, light and electron microscopic examinations of laminar tissue specimens were performed. RESULTS: During hemoperfusion of the isolated forelimbs, mean +/- SD glucose consumption was 197.4 +/- 65.1 mg/h, lactate generation was 1.84 +/- 0.79 mmol/h, and oxygen consumption was 6.4 x 10(-6) +/- 8.9 x 10(-5) mL.g(-1).min(-1). Neither an efflux of potassium into the perfusate nor a relevant increase of the lactate dehydrogenase activity was detected, indicating low amounts of cellular damage in the perfused tissues. Weight gain of forelimbs was 1.02 +/- 0.95%. Histologic and ultrastructural appearance of the laminar tissue revealed no signs of tissue damage. CONCLUSIONS AND CLINICAL RELEVANCE: Isolated equine limbs were perfused under physiologic conditions over a period of < or = 10 hours without structural damage to the laminar tissue.

Quantitative differences in activities of back and pelvic limb muscles during walking and trotting between chronically lame and nonlame horses.

OBJECTIVE: To assess differences in activities of back and pelvic limb muscles by use of surface electromyography (SEMG) in chronically lame and nonlame horses during walking and trotting. ANIMALS: 12 nonlame horses and 12 horses with unilateral chronic mild to moderate pelvic limb lameness. PROCEDURES: On each horse, bipolar electrodes were attached to the skin over the midpoints of the right and left longissimus thoracis (Lot), semitendinosus (Set), biceps femoris (Bif), gluteus medius (Glm), and extensor digitorum longus (Edl) muscles. For each muscle, synchronous kinematic and SEMG recordings were made during walking and trotting on a treadmill; mean, maximum, and minimum muscle activities and maximum-to-mean and minimum-to-mean activity ratios were determined. For each lame or nonlame horse, data from both pelvic limbs were averaged; in lame horses, data from the nonlame and lame pelvic limbs were also examined separately (NL-L and L-L values, respectively). Comparisons were made among the 4 data sets and between gaits. RESULTS: During walking, the NL-L maximum-to-mean ratios for Bif and Glm muscles were significantly greater and in lame horses, L-L and NL-L minimum-to-mean ratios for Set, Bif, Glm, and Lot muscles were significantly less than those for nonlame horses. During trotting, minimum-to-mean ratios for Set, Glm, and Lot muscles in lame horses were significantly lower than those for nonlame horses. Activity of the Edl muscle was not affected by lameness. CONCLUSIONS AND CLINICAL RELEVANCE: In lame horses, variation in muscle use was detectable via SEMG. In chronically lame horses, back and pelvic limb muscle activities were affected differently during walking and trotting.