Developing Sustainable Livestock Systems through Participatory Farmer Research

Application Understanding muscular adaptations could inform objective lameness-detection for early diagnosis/treatment, ultimately serving to detect sub-clinical issues in supposed healthy horses and to reduce pain/ incapacity in lame horses. Introduction The prevalence and impact of lameness on equine welfare has led to extensive research, which has biomechanically analysed lameness-related alterations in movement. Despite this, limited information is available about adaptive muscle activity that facilitates movement during lameness. Surface electromyography (sEMG) is a non-invasive method for quantifying muscle activity. However, no equine studies have employed sEMG to compare inherent and adaptive activity during non-lame and standardised lameness conditions, respectively. The aim of this preliminary study was to compare Triceps Brachii (TB) muscle activity in horses before and after induced forelimb (FL) lameness, using sEMG data. Material and methods Six clinically non-lame horses (5 mares, 1 stallion, age: 7.0±3.7 years, height: 162.3±4.0 cm, body mass: 572.7±45.8 kg) were used. sEMG sensors (Delsys Trigno, Delsys Inc.) were attached bilaterally to locations above TB (long head), that were prepared by removing all hair and cleaning with isopropyl alcohol. Retro-reflective markers were attached to anatomical landmarks for quantitative lameness evaluation (QHorse, Qualisys AB) and gait event detection. sEMG (2000 Hz) and 3D kinematic (200 Hz) data were synchronously collected from horses during in-hand trot trials, conducted on a straight, hard surfaced runway before (baseline) and after FL lameness induction. Baseline data were initially collected, then temporary, mild FL lameness (2-3/5 AAEP Lameness Scale) was induced using mechanical bolt pressure, applied to the tip of the frog and monitored by qualified veterinarians (T.S., F.S.B.) using a modified horseshoe (Merkens and Schamhardt, 1988). Left and right FL lameness induction were randomised. Following data collection, the bolt/ sole pressure was removed and no horses showed adverse reactions to lameness inductions, or residual lameness. For stride segmentation, gait events were detected using kinematic data that were low-pass filtered (Butterworth 4th order, 10 Hz cut-off) and analysed in accordance with the methods described by Holt et al. (2017). To quantify lameness, MinDiff was calculated using poll vertical displacement data, where healthy horses exhibit MinDiff between -6 – 6mm and left and right FL lameness are exhibited as more positive and negative values, respectively (Rhodin et al., 2016). Raw sEMG signals were DC-offset removed, high-pass filtered (Butterworth 4th order, 40 Hz cut-off) (St. George et al., 2018), and fullwave rectified. Integrated EMG (iEMG) and average rectified value (ARV) were calculated using stride duration as temporal domain. To reduce inter-subject variability, iEMG and ARV from each horse were normalised to the maximum value observed for each limb (left/ right FL) across all strides from the baseline condition. Data from the “lame” and “nonlame” limb were grouped, according to the limb where lameness was induced. A 2x2 repeated measures ANOVA was used to compare muscle activity between limb (lame, non-lame) and condition (baseline, induced FL lameness). Post-hoc analyses using Bonferroni correction were performed where significant main effects were found. Results Mean ± sd MinDiff were baseline:-1.8 ± 8.7 mm, left FL lameness induction:-55.3 ± 34.1 mm, right FL lameness: 56.8 ± 17.9 mm. Significant interactions between limb and condition were found for iEMG (p < 0.05, n2=0.74) and ARV (p < 0.05, n2=0.75). Post hoc analyses of iEMG and ARV data revealed muscle activity was significantly higher in the lame limb (p < 0.05) and significantly lower in the non-lame limb (p < 0.01) during the induced FL lameness condition. Conclusion Preliminary findings reveal neuromuscular adaptations in TB during induced FL lameness. Significant increases in stance duration have been reported during FL lameness (Weishaupt et al., 2006). Therefore, significant increases in lame limb muscle activity may be due to prolonged stabilisation of the shoulder and elbow joints, as a compensatory mechanism of gait adaptation to lameness. Further investigations of additional muscles and chronic lameness cases are required to determine whether sEMG can provide a complimentary tool for objective lameness detection

Reliability of surface electromyographic (sEMG) measures of equine axial and appendicular muscles during overground trot

The reliability of surface electromyography (sEMG) has not been adequately demonstrated in the equine literature and is an essential consideration as a methodology for application in clinical gait analysis. This observational study investigated within-session, intra-subject (stride-to-stride) and inter-subject reliability, and between-session reliability of normalised sEMG activity profiles, from triceps brachii (triceps), latissimus dorsi (latissimus), longissimus dorsi (longissimus), biceps femoris (biceps), superficial gluteal (gluteal) and semitendinosus muscles in n = 8 clinically non-lame horses during in-hand trot. sEMG sensors were bilaterally located on muscles to collect data during two test sessions (session 1 and 2) with a minimum 24-hour interval. Raw sEMG signals from ten trot strides per horse and session were DC-offset removed, high-pass filtered (40 Hz), full-wave rectified, and low-pass filtered (25 Hz). Signals were normalised to peak amplitude and percent stride before calculating intra- and inter-subject ensemble average sEMG profiles across strides for each muscle and session. sEMG profiles were assessed using waveform similarity statistics: the coefficient of variation (CV) to assess intra- and inter-subject reliability and the adjusted coefficient of multiple correlation (CMC) to evaluate between-session reliability. Across muscles, CV data revealed that intra-horse sEMG profiles within- and between-sessions were comparatively more reliable than inter-horse profiles. Bilateral gluteal, semitendinosus, triceps and longissimus (at T14 and L1) and right biceps showed excellent between-session reliability with group-averaged CMCs > 0.90 (range 0.90–0.97). Bilateral latissimus and left biceps showed good between-session reliability with group-averaged CMCs > 0.75 (range 0.78–0.88). sEMG profiles can reliably describe fundamental muscle activity patterns for selected equine muscles within a test session for individual horses (intra-subject). However, these profiles are more variable across horses (inter-subject) and between sessions (between-session reliability), suggesting that it is reasonable to use sEMG to objectively monitor the intra-individual activity of these muscles across multiple gait evaluation sessions at in-hand trot

Local therapy of cancer with free IL-2

This is a position paper about the therapeutic effects of locally applied free IL-2 in the treatment of cancer. Local therapy: IL-2 therapy of cancer was originally introduced as a systemic therapy. This therapy led to about 20% objective responses. Systemic therapy however was very toxic due to the vascular leakage syndrome. Nevertheless, this treatment was a break-through in cancer immunotherapy and stimulated some interesting questions: Supposing that the mechanism of IL-2 treatment is both proliferation and tumoricidal activity of the tumor infiltrating cells, then locally applied IL-2 should result in a much higher local IL-2 concentration than systemic IL-2 application. Consequently a greater beneficial effect could be expected after local IL-2 application (peritumoral = juxtatumoral, intratumoral, intra-arterial, intracavitary, or intratracheal = inhalation). Free IL-2: Many groups have tried to prepare a more effective IL-2 formulation than free IL-2. Examples are slow release systems, insertion of the IL-2 gene into a tumor cell causing prolonged IL-2 release. However, logistically free IL-2 is much easier to apply; hence we concentrated in this review and in most of our experiments on the use of free IL-2. Local therapy with free IL-2 may be effective against transplanted tumors in experimental animals, and against various spontaneous carcinomas, sarcomas, and melanoma in veterinary and human cancer patients. It may induce rejection of very large, metastasized tumor loads, for instance advanced clinical tumors. The effects of even a single IL-2 application may be impressive. Not each tumor or tumor type is sensitive to local IL-2 application. For instance transplanted EL4 lymphoma or TLX9 lymphoma were not sensitive in our hands. Also the extent of sensitivity differs: In Bovine Ocular Squamous Cell Carcinoma (BOSCC) often a complete regression is obtained, whereas with the Bovine Vulval Papilloma and Carcinoma Complex (BVPCC) mainly stable disease is attained. Analysis of the results of local IL-2 therapy in 288 cases of cancer in human patients shows that there were 27% Complete Regressions (CR), 23% Partial Regressions (PR), 18% Stable Disease (SD), and 32% Progressive Disease (PD). In all tumors analyzed, local IL-2 therapy was more effective than systemic IL-2 treatment. Intratumoral IL-2 applications are more effective than peritumoral application or application at a distant site. Tumor regression induced by intratumoral IL-2 application may be a fast process (requiring about a week) in the case of a highly vascular tumor since IL-2 induces vascular leakage/edema and consequently massive tumor necrosis. The latter then stimulates an immune response. In less vascular tumors or less vascular tumor sites, regression may require 9–20 months; this regression is mainly caused by a cytotoxic leukocyte reaction. Hence the disadvantageous vascular leakage syndrome complicating systemic treatment is however advantageous in local treatment, since local edema may initiate tumor necrosis. Thus the therapeutic effect of local IL-2 treatment is not primarily based on tumor immunity, but tumor immunity seems to be useful as a secondary component of the IL-2 induced local processes. If local IL-2 is combined with surgery, radiotherapy or local chemotherapy the therapeutic effect is usually greater than with either therapy alone. Hence local free IL-2 application can be recommended as an addition to standard treatment protocols. Local treatment with free IL-2 is straightforward and can readily be applied even during surgical interventions. Local IL-2 treatment is usually without serious side effects and besides minor complaints it is generally well supported. Only small quantities of IL-2 are required. Hence the therapy is relatively cheap. A single IL-2 application of 4.5 million U IL-2 costs about 70 Euros. Thus combined local treatment may offer an alternative in those circumstances when more expensive forms of treatment are not available, for instance in resource poor countries

The existence of intertransverse joints in young warmblood foals

OBJECTIVE: To verify the existence of intertransverse joints (ITJs) in young foals. ANIMALS: 11 warmblood foals. PROCEDURES: Postmortem examination of the lumbar area in foals < 200 days old using CT, MRI, dissection, and histomorphology. Data were analyzed with descriptive statistics. RESULTS: Age of foals varied between 1 and 200 days (median, 11 days). Ten foals had 6 lumbar (L) vertebrae, and 1 foal had 5. All 11 foals, irrespective of age, had ITJs between the first sacral and last lumbar vertebrae and between the last and second-to-last lumbar vertebrae. In 6 foals (all with 6 L vertebrae), ITJs also existed between the fourth and fifth L vertebra. One foal, also with 6 L vertebrae, additionally had a unilateral (right) ITJ between the transverse processes of the third and fourth L vertebra. Based on CT, width of ITJs was seemingly greater in young (< 1 month old) foals because of the incomplete ossification of the transverse processes. The ITJs were confirmed and further characterized by MRI, dissection, and histomorphology. CLINICAL RELEVANCE: ITJs already exist in very young warmblood foals and are present at birth. During the first months of life, these juvenile ITJs develop similarly to other synovial joints with increasing ossification and concomitant decrease of thickness of the cartilage layer. Knowledge of the presence of these ITJs in young animals is clinically relevant, as they should be recognized as nonpathologic when for instance a young foal is presented for presumed arthropathy and examined with advanced imaging techniques

Mare and foal survival and subsequent fertility of mares treated for uterine torsion

REASONS FOR PERFORMING STUDY: Previous surveys have reported mare and foal survival after correction of uterine torsion varies from 60-84% and 30-54%, respectively. Furthermore, resolution via a standing flank laparotomy (SFL) has been associated with better foal, but not mare, survival. OBJECTIVES: To compare the success of SFL with other correction methods (e.g. midline or flank laparotomy under general anaesthesia; correction per vaginam). STUDY DESIGN: Retrospective analysis of clinical records. METHODS: Data on correction technique, stage of gestation, degree of rotation, survival and subsequent fertility for 189 mares treated for uterine torsion (UT) at 3 equine referral hospitals in the Netherlands during 1987-2007 were analysed. RESULTS: Mean stage of gestation at diagnosis was 283 days (range 153-369) with the majority of UTs (77.5%) occurring before Day 320 of gestation. After UT correction, 90.5% of mares and 82.3% of foals survived to hospital discharge, between 3 and 39 days later, and to foaling. Multivariable logistic regression indicated that correction method and stage of gestation at UT affected survival of foals and mares. For foals, survival was 88.7% after SFL compared to 35.0% after other methods (P = 0.001). When UT occurred at <320 days, 90.6% of foals survived, compared to 56.1% at ≥320 days (P = 0.007). For mare survival, an interaction between stage of gestation and correction method was detected (P = 0.02), with higher survival after SFL (97.1%) than other methods (50.0%) at <320 days of gestation (P<0.01). When UT occurred at ≥320 days, mare survival did not differ between techniques (76.0% vs. 68.8; P = 0.6). Of 123 mares that were bred again, 93.5% became pregnant; fertility did not differ between mares treated by SFL (93.9%) and other techniques (87.5%; P = 0.9). CONCLUSIONS: SFL is the surgical technique of choice for resolving uncomplicated (i.e. no co-existing gastrointestinal lesions) equine UT except when the stage of gestation exceeds 320 days

The use of surface electromyography for quantification of changes in biceps femoris and triceps brachii muscle activity during induced forelimb and hindlimb lameness

Background: Movement asymmetry during lameness has been extensively studied using quantitative gait analysis, but limited information exists about adaptive muscle activity occurring during lameness. Objectives: To investigate whether asymmetric muscle activity occurs in superficial pelvic and thoracic limb muscles before and after induced forelimb (FL) and hindlimb (HL) lameness using surface electromyography (sEMG). Study Design: Experimental. Methods: sEMG sensors were attached bilaterally above Biceps Femoris (BF) and Triceps Brachii (TB) in a preliminary sample of five clinically non-lame horses. sEMG and 3D-kinematic data were collected during in-hand trot. FL and HL lameness (2-3/5 AAEP) were induced on separate days using a modified horseshoe, with baseline data initially collected each day. To quantify lameness, MinDiff was calculated from poll (HDMin) and pelvis (PDMin) vertical displacement for FL and HL lameness, respectively. Raw sEMG signals were DC-offset removed, high-pass filtered, and full-wave rectified. Integrated EMG (iEMG) was calculated using stride duration as the temporal domain. iEMG from each horse were normalised to the maximum observed value of individual muscles in the baseline condition. The difference between right and left iEMG values for each muscle were calculated for each stride to quantify muscle asymmetry (iEMGDiff). Repeated measures ANOVA compared iEMGDiff data for each muscle between conditions (baseline, induced FL and HL lameness). Results: Absolute mean±sd for HDMin (61.6±27.1) and PDMin (16.0±9.1) were congruent with the degree of induced lameness. Mean±sd baseline iEMGDiff was 14.2±5.7 across both muscles. BFiEMGDiff was significantly greater than baseline (15.2±6.9 vs. 80.9±46.1, p<0.05, pn2=0.704) during HL lameness and TBiEMGDiff during FL lameness (10.0±1.7 vs. 40.7±18.7, p<0.05, pn2=0.754). Main Limitations: Clinical lameness cases must confirm findings. Conclusions: FL and HL lameness cause differential increases in iEMG asymmetry in TB and BF. sEMG symmetry parameters could help understand neuromuscular adaptations to lameness and could compliment kinematic methods for objective lameness evaluation

Rater agreement for assessment of equine back mobility at walk and trot compared to quantitative gait analysis.

BackgroundLameness assessment in horses is still predominantly performed using subjective methods. Visual assessment is known to have moderate to good intra-rater agreement but relatively poor inter-rater agreement. Little is known about inter- and intra-rater agreement on the evaluation of back motion, for which no objective measurement technique in a clinical setting is available thus far.ObjectivesTo describe inter- and intra-rater agreement of visual evaluation of equine back mobility.Study designRater reliability study using a fully crossed design in which all horses are rated by all observers. This data is compared with objective gait analysis.MethodsSeventy equine professionals (veterinarians and physiotherapists) and veterinary students evaluated videos of 12 healthy horses at walk and trot on a hard, straight line. Nine parameters related to back mobility were scored: general mobility, thoracic, lumbar, lumbosacral flexion and extension and left and right thoracolumbar latero-flexion. All parameters were compared with simultaneously measured quantitative motion parameters. After 1 month, six randomly chosen horses were re-evaluated by 57 observers.ResultsFor each parameter inter- and intra-rater agreements were calculated using intra-class correlation coefficients. For all parameters, inter-rater agreement was very poor (Main limitationsHorses were scored from videos and by lack of any existing (semi-) quantitative system, a custom-made system had to be used.ConclusionsThe poor inter- and intra-rater agreements of visual scoring of mobility of the equine back and the disagreement between subjective and objective gait analysis data, demonstrate the need for the development and introduction of objective, quantitative and repeatable techniques to assess equine back motion

Electromyographic and kinematic evaluation of movement and hindlimb muscle activity in horses with temporary forelimb lameness induction

Introduction: Lameness is the most prevalent cause of occupational disability in horses, but limited information is available about adaptive muscle activity that facilitates movement during lameness. Forelimb (FL) lameness is known to provoke a secondary compensatory hindlimb (HL) lameness and it is hypothesised that this is reflected in HL muscle activity. The aim of this study was to compare Biceps Femoris (BF) muscle activity in horses before and after induced FL lameness using surface electromyography (sEMG). Methods: Six clinically non-lame horses (5 mares, 1 stallion, age: 9.0±4.3 years, height: 160.7±4.6 cm, body mass: 581.5±47.4 kg) were used. sEMG sensors were attached bilaterally above BF. sEMG (2000Hz) and 3D kinematic (200Hz) data were synchronously collected from horses during in-hand trot trials, conducted on a hard runway before (baseline) and after FL lameness induction. Baseline data were initially collected, then temporary, mild FL lameness (2-3/5 AAEP) was induced and monitored by qualified veterinarians using a modified horseshoe (Merkens and Schamhardt, 1988). For stride segmentation, kinematic gait events were detected (Holt et al., 2017). To quantify lameness, MinDiff was calculated using poll vertical displacement data (Rhodin et al., 2018). Raw sEMG signals were DC-offset removed, high-pass filtered (St. George et al., 2018), and full-wave rectified. Integrated EMG (iEMG) was calculated using stride duration as temporal domain. iEMG from each horse were normalised to the maximum value observed for each HL across all strides from baseline condition. Difference between left and right iEMG values were calculated for each stride as a measure of muscle activity asymmetry (iEMGDiff). Repeated measures ANOVA compared iEMGDiff between conditions (baseline, induced FL lameness). Results: Mean±sd MinDiff were baseline:-1.8±8.7 mm, left FL lameness induction:-55.3±34.1 mm, right FL lameness induction: 56.8±17.9 mm. Mean±sd iEMGDiff were 14.9±4.9 and 37.2±35.0 for baseline and FL lameness induction, respectively, but differences between conditions were non-significant (p=0.17, n2=0.34). Conclusions: Compensatory pelvic movement is variable and less pronounced during FL lameness and high inter-individual iEMGDiff variability was observed. This may explain non-significant differences in BF muscle activity, but further research must confirm this

Is sEMG a repeatable measure of muscle activity in horses – between-day repeatability at in-hand trot

The repeatability of surface electromyography (sEMG) is an important consideration for its potential clinical application in equine gait analysis. We hypothesize that equine sEMG profiles are repeatable between measurement sessions, but this has not been demonstrated. Thus, we evaluated the between-day repeatability of normalised sEMG activity profiles, from triceps brachii (triceps), latissimus dorsi (latissimus), longissimus dorsi (longissimus), biceps femoris (biceps), superficial gluteal (gluteal) and semitendinosus in n=8 clinically non-lame horses. sEMG sensors (Trigno, Delsys Inc.) were bilaterally located on muscles to collect data during in-hand trot on two occasions (day 1: 3.11±0.23 m/s, day 2: 3.07±0.35 m/s) with a minimum 24-hour interval. Raw sEMG signals from ten trot strides per horse and day were DC-offset removed, high-pass filtered (40 Hz), full-wave rectified, low-pass filtered (25 Hz), and normalised with respect to peak amplitude and percent stride. Within-subject, ensemble average sEMG profiles across strides from each muscle and day were calculated. The adjusted coefficient of multiple correlation (CMC) was used to evaluate the between-day repeatability of ensemble average sEMG profiles and tends to 1 when waveforms are similar. Bilateral gluteal, semitendinosus, triceps and longissimus (at T14 and L1) and left biceps showed excellent between-day repeatability with group-averaged CMCs>0.90 (range 0.90- 0.97). Bilateral latissimus and right biceps showed good reliability with group-averaged CMCs>0.75 (range 0.78-0.88). The sEMG profiles studied here are consistent across days, suggesting that it is reasonable to use sEMG to objectively monitor the activity of these muscles across multiple gait evaluation sessions at trot