Partial herd hoof trimming results in a higher economic net benefit than whole herd hoof trimming in dairy herds.

Sole ulcers, a common cause of lameness is the costliest non-infectious foot lesion in dairy cows and one of the most prevalent non-infectious foot lesions in freestall housing systems. Costs associated with sole ulcers are treatment costs, plus increased labor and decreased productivity and fertility. Routine hoof trimming is part of a strategy to manage sole ulcers. However, hoof trimming strategies differ among farms. The two most frequently applied strategies are: 1) partial herd hoof trimming with a 2-month interval between trims; and 2) whole herd hoof trimming at 6-month intervals. A Markov model was developed to investigate whether every 2 months partial herd hoof trimming or whole herd hoof trimming every 6 months was the most cost-effective strategy to avoid costs associated with sole ulcers. In this model, the net benefits for a 100-cow herd and the average productive life span of a dairy cow in intensive dairy systems of 3 years were evaluated. Partial herd hoof trimming was the most cost-effective strategy 100% of the time compared to whole herd hoof trimming, with a difference in 3-year net benefits of US$4,337 (95% CI: US$2,713-US$5,830). Based on sensitivity analyses, variables that were the sources of the biggest uncertainty in the model were herd size, the probability of being trimmed in a partial herd trim, and the prevalence of sole ulcers. To further investigate the impacts of herd size and of probability of being trimmed, various scenario analyses were conducted. With increasing herd size, the difference in net benefits in favor of partial herd hoof trimming increased even more. Scenario analyses about the probability of getting trimmed all indicated that targeted intervention increased the difference in net benefits in favor of partial herd hoof trimming. However, if the selection of cows to be trimmed in a partial herd trim was random, the whole herd hoof trimming strategy became cost-effective. Therefore, targeted selection and early intervention are necessary to decrease costs associated with sole ulcers.

DEVELOPMENT AND EVALUATION OF A STANDARDIZED SYSTEM FOR THE ASSESSMENT OF LOCOMOTOR HEALTH IN ELEPHANTS UNDER HUMAN CARE.

Although lameness is a common problem in elephants (Asian elephant [Elephas maximus] and African elephants Loxodonta africana and Loxodonta cyclotis) under human care, there has not been a standardized lameness assessment system to date. This study developed and evaluated a standardized system for the assessment of locomotion in elephants under human care regardless of husbandry system. In total, 72 elephants out of a possible 73 in the United Kingdom and Ireland were filmed from behind, from in front, and from both sides. Using a questionnaire and a select panel of elephant specialists, a zoo veterinarian, and a locomotion expert, a numerical rating scoring (NRS) system was proposed. Locomotion was scored on a 4-point scale with numerical values 0-4 corresponding to specific criteria as follows: 0 = clinically sound, 1 = stiffness, 2 = abnormal tracking, and 4 = reluctance to bear weight. The intra- and interobserver repeatability of five veterinary surgeons using this system was determined and compared with a visual analog scale (VAS) expressed as a 100-mm line. Overall intraobserver reliability was moderate (Cohen's kappa [κ] = 0.676) and interobserver reliability was fair (κ = 0.37) for the presence of lameness. Interobserver agreement improved from the first scoring to second scoring from slight agreement to fair agreement for stiffness and reluctance to bear weight. Abnormal tracking had moderate intraobserver agreement for both scoring sessions. There were wide widths of agreement for the VAS interobserver (67 mm); however, they were narrower for the intraobserver (33 mm). The developed NRS can be used on freely moving elephants to evaluate elephant locomotion, regardless of husbandry methods, and has been shown to be more reliable than a VAS.

18F-sodium fluoride positron emission tomography provides pertinent additional information to computed tomography for assessment and management of tarsal pain in horses.

OBJECTIVE: To assess the value of 18F-sodium fluoride (18F-NaF) positron emission tomography (PET) for imaging the tarsus and proximal metatarsus and compare it with CT and lameness evaluation. ANIMALS: 25 horses with lameness localized to the tarsal and proximal metatarsal regions that underwent 18F-NaF PET/CT between 2016 and 2021. METHODS: 18F-NaF PET and CT images were retrospectively independently evaluated by 3 observers. Standardized uptake values (SUV) were used to characterize 18F-NaF uptake. Correlation between PET and CT findings with subjective and objective maximum (Max-D) and minimum pelvic height lameness data was estimated. RESULTS: The inter-observer Kappa-weighted value (κ) was higher for PET (κ = 0.66) than CT (κ = 0.6). CT and PET scores were fairly correlated (R = 0.49; P < 0.05). PET SUVratio (SUV of the main lesion/SUV talus) had the highest correlation with Max-D (R = 0.71; P < .05). PET and CT scores for the plantar region were significantly higher in Quarter Horses (P < .05) and showed consistently higher correlation with objective lameness data (CT plantar grade - Max-D [R = 0.6; P < .05], PET plantar grade - Max-D [R = 0.47; P = .04]) than other regions of the distal tarsal joints. Three Warmbloods presented marked uptake at the medial cochlea of the distal tibia. CLINICAL RELEVANCE: PET had a moderate correlation with CT for assessment of tarsal lesions. The degree of PET uptake can help differentiate active versus inactive lesions. Specific location of the uptake is important in determining clinical relevance.

Assessment of calcium, phosphorus, magnesium, vitamin D and PTH levels in sera of lame horses.

BACKGROUND: Minerals play vital roles in physiologic processes. Calcium, phosphorus and magnesium are common minerals. Secretion, absorption and homeostasis of these minerals are affected by associations between the active vitamin D and parathyroid hormone (PTH). OBJECTIVE: The aim of this study was to assess concentrations of vitamin D, PTH and minerals, such as calcium, phosphorus and magnesium in horse sera, as well as associations of these values with lameness in horses. In the references, the reasons for lameness can be deficiency and imbalance of minerals, and clinical observations also confirm this and there is still not enough information regarding the relationship between mineral imbalance and lameness of horses. The prominent forms of lameness include navicular syndrome, back pain, splints, ring bone, side bone, non-infectious arthritis and bucked shins. Deficiency and inadequacy of calcium, phosphorous and magnesium have been regarded as predisposing and aggravating factors of the aforementioned diseases. MATERIALS AND METHODS: This cross-sectional study was carried out on 60 horses, including 30 lame and 30 healthy adult horses, summer to fall 2021. Levels of calcium, phosphorus, magnesium, vitamin D and PTH were assessed in sera using automatic analyser, atomic absorption spectroscopy and commercially available kits. RESULTS: The average level of calcium was higher healthy horses than lame horses in the two seasons (p < 0.001). The average level of inorganic phosphorus in horses was higher in summer than autumn (p < 0.001). The mean magnesium concentration in healthy horses was greater than lame horses in the two seasons (p < 0.01). In this study, the mean PTH concentration in healthy horses was lower in fall than summer (p < 0.05). CONCLUSION: The low average levels of calcium and magnesium in lame horses in the two seasons indicate critical roles of calcium and magnesium in the normal function of the horse musculoskeletal system as well as prevention of lameness.

Multifactorial assessment of leukocyte reduced platelet rich plasma injection in dogs undergoing tibial plateau leveling osteotomy: A retrospective study.

This study assessed the effects of concurrent intra-articular injection and Tibial Plateau Leveling Osteotomy (TPLO) plate surface treatment with leukoreduced platelet rich plasma (lPRP) on outcomes of dogs undergoing TPLO. A retrospective study of medical records for cases presenting from January 2018 to December 2020 was performed. Client-owned dogs with naturally occurring cranial cruciate ligament rupture that underwent TPLO surgery were divided into two groups. The lPRP group included cases that underwent intra-articular injection and plate surface treatment at the time of their TPLO. The control group (C) underwent TPLO without PRP treatment. Data analyzed included: presence of surgical site infection, implant removal rate, degree of change in OA progression score, lameness score progression and radiographic bone healing. The short- and long-term complication rate, hospitalization and antibiotic therapy were also compared between the groups. Descriptive statistics, comparison analyses (Chi square test, t-test, Fisher's exact test) and multi-level logistic regression models were used for statistical analysis. A total of 110 cases met the study inclusion criteria: 54 = lPRP, 56 = C. There were no significant differences between groups with regard to gender, age, presence of meniscal tear, weight, or body condition score. Significant findings included: improved radiographic healing of the osteotomy in the lPRP group, improved global OA scores in the lPRP group, and improved lameness score at recheck examination in the lPRP group. There was no significant difference between the lPRP and C group with regard to surgical site infection and implant removal rate. Concurrent intra-articular injection and plate surface treatment with leukocyte reduced PRP at the time of TPLO, is beneficial in slowing the progression of OA, hastening the radiographic evidence of osteotomy healing, and improved lameness score on recheck examination. Leukocyte reduced PRP was not a significant factor in reducing SSI or implant removal rate.

Cost of lameness in dairy herds: An integrated bioeconomic modeling approach.

Foot disorders are costly health disorders in dairy farms, and their prevalence is related to several factors such as breed, nutrition, and farmer's management strategy. Very few modeling approaches have considered the dynamics of foot disorders and their interaction with farm management strategies within a holistic farm simulation model. The aim of this study was to estimate the cost of foot disorders in dairy herds by simulating strategies for managing lameness. A dynamic and stochastic simulation model (DairyHealthSim) was used to simulate the herd dynamics, reproduction management, and health events. A specific module was built for lameness and related herd-level management strategies. Foot disorder occurrences were simulated with a base risk for each etiology [digital dermatitis (DD), interdigital dermatitis, interdigital phlegmon, sole ulcer (SU), white line disease (WLD)]. Two state machines were implemented in the model: the first was related to the disease-induced lameness score (from 1 to 5), and the second concerned DD-state transitions. A total of 880 simulations were run to represent the combination of the following 5 scenarios: (1) housing (concrete vs. textured), (2) hygiene (2 different scraping frequencies), (3) the existence of preventive trimming, (4) different thresholds of DD prevalence detected and from which a collective footbath is applied to treat DD, and (5) farmer's ability to detect lameness (detection rate). Housing, hygiene, and trimming scenarios were associated with risk factors applied for each foot disorder etiologies. The footbath and lameness detection scenarios both determined the treatment setup and the policy of herd observance. The economic evaluation outcome was the gross margin per year. A linear regression model was run to estimate the cost per lame cow (lameness score ≥3), per case of DD and per week of a cow's medium lameness duration. The bioeconomic model reproduced a lameness prevalence varying from 26 to 98% depending on the management scenario, demonstrating a high capacity of the model to represent the diversity of the field situations. Digital dermatitis represented half of the total lameness cases, followed by interdigital dermatitis (28%), SU (19%), WLD (13%), and interdigital phlegmon (4%). The housing scenarios dramatically influenced the prevalence of SU and WLD, whereas scraping frequency and threshold for footbath application mainly determined the presence of DD. Interestingly, the results showed that preventive trimming allowed a better reduction in lameness prevalence than spending time on early detection. Scraping frequency was highly associated with DD occurrence, especially with a textured floor. The regression showed that costs were homogeneous (i.e., did not change with lameness prevalence; marginal cost equals average cost). A lame cow and a DD-affected cow cost €307.50 ± 8.40 (SD) and €391.80 ± 10.0 per year on average, respectively. The results also showed a cost of €12.10 ± 0.36 per week-cow lameness. The present estimation is the first to account for interactions between etiologies and for the complex DD dynamics with all the M-stage transitions, bringing a high level of accuracy to the results.

Evaluation of a small-bore needle arthroscope for diagnosis and treatment of medial coronoid disease in dogs: a pilot study with short-term assessment.

CASE HISTORY: Dogs (n = 15) that were presented to a single veterinary teaching hospital with elbow dysplasia-associated lameness between September 2021 and May 2022, and were determined to require arthroscopy based on imaging results, were prospectively recruited into the study. The median duration of lameness was 4 (min 1, max 24) months. CLINICAL FINDINGS: Various breeds were represented with a median body weight of 31.6 (min 15, max 46.4) kg and median age at presentation of 14 (min 8, max 83) months. Results of imaging modalities (CT) were consistent with medial coronoid disease with fissured or fragmented medial coronoid process in all dogs. ARTHROSCOPIC FINDINGS: Feasibility of the needle arthroscopy (NA) procedure was firstly assessed in a preliminary cadaveric study in forelimbs (n = 10) collected from 10 adult dogs euthanised for reasons unrelated to the study. Elbow exploration was performed through a medial approach beginning with NA (1.9 mm 0° angle scope) followed by standard arthroscopy (SA; 2.4 mm 30° angle scope). The quality and extent of visualisation (scored through the number of anatomical structures visualised) were recorded and statistically compared. As the cadaver study indicated that NA allowed safe inspection of all structures in medial/caudal compartments, this procedure was then used in the dogs requiring treatment. In the clinical setting, elbow exploration was successful in all dogs and the treatment (removal of osteochondral fragments) was performed without requiring conversion into SA. One month after surgery, all dogs had an improvement in their lameness score (0-5) and 12/15 dogs were no longer lame. There was a reduction in Canine Orthopaedic Index scores measured a median of 99 (min 47, max 180) days after surgery (24 (IQR 19.5-31.5)) compared to the pre-operative period (49 (IQR 46.5-57); p < 0.001). CLINICAL RELEVANCE: Needle arthroscopy-assisted removal of osteochondral fragments was performed in all dogs with satisfactory short-term clinical outcome. NA is a feasible technique for diagnosis and lesion assessment in dogs with a fissured or fragmented coronoid process. Larger clinical studies with longer follow-up are necessary to validate the NanoScope operative arthroscopy system as an alternative strategy to SA for video-assisted treatment of medial coronoid disease.

Measuring lameness prevalence: Effects of case definition and assessment frequency.

Lameness assessments are commonly conducted at a single point in time, but such assessments are subject to multiple sources of error. We conducted a longitudinal study, assessing the gait of 282 lactating dairy cows weekly during the first 12 wk of lactation, with the aim of assessing how lameness prevalence changed in relation to case definition and assessment frequency. Gait was scored using a 5-point scale where scores of 1 and 2 were considered sound, 3 was clinically lame, and 4 and 5 were severely lame. We created 5 lameness definitions using increasingly stringent thresholds based upon the number of consecutive events of locomotion score ≥3. In LAME1, a cow was considered lame when locomotion score was ≥3 at any scoring event, in LAME2, LAME3, LAME4, and LAME5, a cow was considered lame when locomotion score was 3 or higher during 2, 3, 4, and 5 consecutive scoring events, respectively. We also assessed the effect of assessment frequency on measures of prevalence and incidence using weekly assessment (ASSM1), 1 assessment every 2 wk (ASSM2), 1 assessment every 3 wk (ASSM3), and 1 assessment every 4 wk (ASSM4). Using LAME1, 69.2% of cows were considered lame at some point during the trial, with an average point prevalence of 31.8% (SD: 2.8) and average incidence rate of 10.9 cases/100 cow weeks (SD: 3.7). Lameness prevalence decreased to 28.0% when using LAME5. Survival analysis was used to assess the effects of parity, using these different case definitions. Parity is a known risk for lameness, such that case definitions and prevalence estimates should be stratified by parity to inform management decisions. Using the LAME3 criterion, primiparous cows had the highest chance of reaching 12 wk without a lameness event, and fourth and higher parities had the lowest. Weighted linear and quadratic kappa values were used to assess agreement between different assessment frequencies and lameness definitions; we found substantial to excellent agreement between ASSM1 and ASSM2 using LAME1, LAME2, and LAME3 definitions. Agreement was fair to substantial between ASSM1 and ASSM3 and low to fair between ASSM1 and ASSM4. Likewise, the agreement between LAME1 and LAME2 was fair in primiparous cows, substantial in second and third parity cows, and poor to fair in fourth and greater parity cows. We conclude that lameness prevalence estimates are dependent upon case definition and that the use of more stringent case definitions results in fewer cows classified as lame. These results suggest that routine locomotion assessments be conducted at least every 2 wk, and that cows should be defined as lame on the basis of 2 consecutive assessments.

Expert visual assessment strategies for equine lameness examinations in a straight line and circle: A mixed methods study using eye tracking.

BACKGROUND: A large number of lameness indicators have been suggested for the visual equine lameness assessment. However, it remains unknown which of these are commonly used by experts. METHODS: Twenty-four expert lameness assessors from 10 leading UK institutions viewed 28 video clips of sound and mildly lame horses (median score 2/10). Horses were shown at trot in a straight line (rear and front view) and circle (side view, left and right rein). Eye tracking data were collected at 60 Hz while participants evaluated each clip. A questionnaire captured contextual information. RESULTS: During assessment on the straight line, participants consistently looked mostly at the head and pelvis. On the circle, many participants consistently looked at the head, yet the subsequent choice, weighting and order of examined body regions was unsystematic between and within participants, and there was a bias towards prolonged assessment of the horse's front region. Questionnaires revealed different descriptions of lameness indicators for the same body region and different approaches to decision making under uncertainty. CONCLUSION: In contrast to reasonably high similarity on the straight line, expert veterinarians have not developed a consistent assessment approach when evaluating horses on the circle. The reliability of various lameness indicators on the circle requires a stronger evidence base for a more systematic, repeatable approach.

DEVELOPMENT OF A MOBILITY ASSESSMENT SCORE FOR EVALUATION OF THE EFFECTS OF ORAL HYALURONIC ACID ON CLINICAL LAMENESS IN ASIAN SMALL-CLAWED OTTERS (AONYX CINEREA) AND AFRICAN SPOT-NECKED OTTERS (HYDRICTIS MACULICOLIS) UNDER HUMAN CARE.

Oral hyaluronic acid has been shown to reduce inflammation and pain in humans with osteoarthritis. Eight Asian small-clawed otters (Aonyx cinerea) and two African spot-necked otters (Hydrictis maculicolis) with varying degrees of osteoarthritic changes identified on radiographs were selected for a randomized, double-blinded, placebo-controlled clinical trial. Animal husbandry staff completed otter mobility assessment (OMA) questionnaires for each animal prior to study commencement and following either oral hyaluronic acid at a loading dose of 4 mg/kg PO SID for 10 d followed by a maintenance dose of 2 mg/kg PO SID for 20 d, or placebo for 30 d. Four veterinarians with experience assessing otters watched randomized videos of otter gaits and assigned a clinical lameness score. Two additional evaluators watched the videos: an experienced veterinarian in small animal practice and a final-year veterinary student. All evaluators for OMA and clinical lameness score were blinded to treatment group. Radiographs performed prior to, and following, the study were assessed by a board-certified radiologist (Dennison). The OMA questionnaire had high reliability coefficients and correlated strongly with clinical gait scores and radiographic assessment. Although hyaluronic acid appears to be safe for use in otters at the dose described, there was no observed significant effect of hyaluronic acid on clinical lameness scores, OMA scores, or radiographic assessment of the limbs. The development of the OMA questionnaire is a promising tool for evaluating lameness in managed-care otters and may be further validated in future studies investigating therapeutics or incorporated as a component of animal welfare assessment.

Robustness of five different visual assessment methods for the evaluation of hindlimb lameness based on tubera coxarum movement in horses at the trot on a straight line.

BACKGROUND: The evaluation of hindlimb lameness remains a major challenge in everyday clinical practice. In the absence of clear guidelines, veterinarians use different visual assessment methods for this task whose robustness is unknown. OBJECTIVES: Determination of the robustness of five visual hindlimb lameness assessment methods based on the comparison of left and right tuber coxae movement. STUDY DESIGN: Validated mathematical hindlimb lameness model based on experimental data from the literature. METHODS: Vertical movement of left (LTC) and right (RTC) tuber coxae was simulated for the range of common hindlimb lameness movement patterns that horses present within practice. Lameness severity ranged from sound to moderately lame (0% to 60% motion asymmetry). The scenarios of a pelvis held tilted and asymmetrical pelvic roll were included to reflect possible adaptations in pelvic rotation. Across all conditions, the outcomes for five different visual assessment methods based on comparative tubera coxarum movement were quantified, including hip hike, -drop and range of motion. The robustness of each assessment method was established through comparison to sacrum-based overall motion asymmetry as the ground truth. RESULTS: Tubera coxarum-based lameness assessment was highly sensitive to all the unique lameness patterns and changes in pelvic rotation which a lame horse may adopt. None of the five visual lameness assessment methods was 100% robust across all conditions tested. For everyday clinical practice, comparing the upward movement amplitude of the RTC before right hind foot contact and of the LTC before left hind foot contact (Hip_hike_diff) would be the most robust single tubera coxarum-based visual assessment method. MAIN LIMITATIONS: In the absence of published data regarding the frequency of different movement patterns and hip rotation adaptations in clinical practice, this study cannot indicate the proportion of assessments that would be incorrect for a given visual assessment method. CONCLUSIONS: Using a single tubera coxarum-based visual hindlimb lameness assessment method may lead to incorrect clinical judgement. Therefore, using multiple assessment methods would be beneficial to substantiate impressions.

Visual lameness assessment in comparison to quantitative gait analysis data in horses.

BACKGROUND: Quantitative gait analysis offers objective information to support clinical decision-making during lameness workups including advantages in terms of documentation, communication, education, and avoidance of expectation bias. Nevertheless, hardly any data exist comparing outcome of subjective scoring with the output of objective gait analysis systems. OBJECTIVES: To investigate between- and within-veterinarian agreement on primary lame limb and lameness grade, and to determine relationships between subjective lameness grade and quantitative data, focusing on differences between (1) veterinarians, (2) live vs video assessment, (3) baseline assessment vs assessment following diagnostic analgesia. STUDY DESIGN: Clinical observational study. METHODS: Kinematic data were compared to subjective lameness assessment by clinicians with ≥8 years of orthopaedic experience. Subjective assessments and kinematic data for baseline trot-ups and response to 48 diagnostic analgesia interventions in 23 cases were included. Between and within-veterinarian agreement was investigated using Cohen's Kappa (κ). Asymmetry parameters for kinematic data ('forelimb lame pattern', 'hindlimb lame pattern', 'overall symmetry', 'vector sum head', 'pelvic sum') were determined, and used as outcome variables in mixed models; explanatory variables were subjective lameness grade and its interaction with (1) veterinarian, (2) live or video evaluation and (3) baseline or diagnostic analgesia assessment. RESULTS: Agreement on lame limb between live and video assessment was 'good' between and within veterinarians (median κ = 0.64 and κ = 0.53). There was a positive correlation between subjective scoring and measured asymmetry. The relationship between lameness grade and objective asymmetry differed slightly between (1) veterinarians (for all combined parameters, p-values between P < .001 and 0.04), (2) between live and video assessments ('forelimb lame pattern', 'overall symmetry', both P ≤ .001), and (3) between baseline and diagnostic analgesia assessment (all combined parameters, between P < .001 and .007). MAIN LIMITATIONS: Limited number of veterinarians (n = 4) and cases (n = 23), only straight-line soft surface data, different number of subjective assessments live vs from video. CONCLUSIONS: Overall, between- and within-veterinarian agreement on lame limb was 'good', whereas agreement on lameness grade was 'acceptable' to 'poor'. Quantitative data and subjective assessments correlated well, with minor though significant differences in the number of millimetres, equivalent to one lameness grade between veterinarians, and between assessment conditions. Differences between baseline assessment vs assessment following diagnostic analgesia suggest that addition of objective data can be beneficial to reduce expectation bias. The small differences between live and video assessments support the use of high-quality videos for documentation, communication, and education, thus, complementing objective gait analysis data.

The hidden cost of disease: II. Impact of the first incidence of lameness on production and economic indicators of primiparous dairy cows.

Lameness is a persistent and underreported health and welfare problem in the dairy industry, resulting in reduced cow performance and profitability as well as early culling. The study objectives were (1) to quantify the impact of the first instance of lameness, at different stages of lactation, on production and economic performance, and (2) to further quantify the impacts of the first instance of lameness when only cows that remain in the herd for at least 100 d in milk (DIM) and those that remain for 305 DIM are included in the analysis. A retrospective longitudinal study was conducted using pre-existing data from animal health records and Dairy Herd Improvement Association records. Data were edited based on selected inclusion criteria, yielding a data set containing records from 15,159 first-lactation Holstein cows from 120 herds with year of first calving between 2003 and 2014. Lame cows were assigned to 1 of 4 groups based on when in the lactation the first event of lameness occurred: transition (1-21 DIM), early lactation (22-100 DIM), mid-lactation (101-200 DIM), or late lactation (201+ DIM). Mid- and late-lactation lame cows were also stratified by cumulative milk yield before the lameness event. Healthy cows (i.e., no recorded lameness event) were randomly assigned for each lactation stage, with mid-lactation healthy and late-lactation healthy cows similarly stratified. Production performance (cumulative milk, fat, and protein yield) and economic performance [milk value, margin over feed cost (MOFC), and gross profit] were analyzed using a mixed model with herd as a random effect. Cumulative milk yields were 811 to 1,290 kg lower for lame cows than for healthy cows, with milk component yields undergoing similar reductions. Reductions in milk yield contributed to losses in milk value (-Can$527 to -Can$1,083; -US$419 to -US$862) and MOFC (-Can$510 to -Can$774; -US$406 to -US$616). Higher losses were reported using gross profit (-Can$753 to -Can$1,052; -US$599 to -US$837), which includes all lameness-related costs. Production and performance losses were smaller when 100 DIM and 305 DIM thresholds were applied (i.e., exclusion of cows culled before 100 and 305 DIM, respectively), however, mid- and late-lactation lame cows maintained high levels of significant losses for all 6 variables analyzed. Lameness also led to higher levels of culling, masking losses for transition and early-lactation lame cows in the 305-DIM analysis. Increasing producer understanding of the costs associated with lameness not only serves to provide insight to producers for more informed culling decisions, but may also help producers weigh the costs of adopting new methods and technologies targeted at reducing on-farm lameness.

Effect of gamified perceptual learning on visual detection and discrimination skills in equine gait assessment.

BACKGROUND: Visual assessment of equine lameness is an everyday veterinary task suffering from poor diagnostic accuracy. The aim of this study was to quantify the impact of the perceptual learning game 'LamenessTrainer' on skill development. METHODS: Thirty-six undergraduate veterinary students engaged in four game modules teaching the assessment of fore- and hindlimb lameness. Computer animations of horses in this game displayed 0% (sound) to 70% (moderately lame) vertical movement asymmetry of head and pelvis. Performance, learning effects, diagnostic accuracy, detection thresholds and survey responses were analysed. RESULTS: Following staircase learning, more than 80% of students reliably classified horses with ≥20% asymmetry for forelimb lameness, ≥40% asymmetry for simplified hindlimb lameness and ≥50% asymmetry for realistic hindlimb lameness. During random presentation, on average 82% of sound and 65% of lame horses were assessed correctly during forelimb lameness evaluation, dropping to 39% of sound and 56% of lame horses for hindlimb lameness. CONCLUSION: In less than two hours, systematic perceptual learning through deliberate practice can develop visual assessment skills to an accuracy level comparable to expert assessors scoring the same animations. Skills should be developed further to improve misclassifications of sound and mildly lame horses, especially for hindlimb lameness evaluation.

Associations between body condition score, locomotion score, and sensor-based time budgets of dairy cattle during the dry period and early lactation.

Lameness, one of the most important disorders in the dairy industry, is related to postpartum diseases and has an effect on dairy cow welfare, leading to changes in cows' daily behavioral variables. This study quantified the effect of lameness on the daily time budget of dairy cows in the transition period. In total, 784 multiparous dairy cows from 8 commercial Dutch dairy farms were visually scored on their locomotion (score of 1-5) and body condition (score of 1-5). Each cow was scored in the early and late dry period as well as in wk 4 and 8 postpartum. Cows with locomotion scores 1 and 2 were grouped together as nonlame, cows with score 3 were considered moderately lame, and cows with scores 4 and 5 were grouped together as severely lame. Cows were equipped with 2 types of sensors that measured behavioral parameters. The leg sensor provided number of steps, number of stand-ups (moving from lying to standing), lying time, number of lying bouts, and lying bout length. The neck sensor provided eating time, number of eating bouts, eating bout length, rumination time, number of rumination bouts, and rumination bout length. Sensor data for each behavioral parameter were averaged between 2 d before and 2 d after locomotion scoring. The percentage of nonlame cows decreased from 63% in the early dry period to 46% at 8 wk in lactation; this decrease was more severe for cows with higher parity. Cows that calved in autumn had the highest odds for lameness. Body condition score loss of >0.75 point in early lactation was associated with lameness in wk 4 postpartum. Moderately lame cows had a reduction of daily eating time of around 20 min, whereas severely lame cows had a reduction of almost 40 min. Similarly, moderately and severely lame dry cows showed a reduction of 200 steps/d, and severely lame cows in lactation showed a reduction of 600 steps/d. Daily lying time increased by 26 min and lying bout length increased by 8 min in severely lame cows compared with nonlame cows. These results indicate a high prevalence of lameness on Dutch dairy farms, with an increase in higher locomotion scores from the dry period into early lactation. Time budgets for multiparous dairy cows differed between the dry period and the lactating period, with a higher locomotion score (increased lameness) having an effect on cows' complete behavioral profile. Body condition score loss in early lactation was associated with poor locomotion postpartum, whereas lameness resulted in less eating time in the dry period and early lactation, creating a harmful cycle.

Assessment of Orthopedic Versus Neurologic Causes of Gait Change in Dogs and Cats.

Diagnosis of forelimb lameness may be challenging, as it not only can be due to multiple common orthopedic diseases but also may occasionally be caused by neurologic disease. A thorough orthopedic and neurologic examination is key to determining which disease category is the likely culprit. Deficits identified on the neurologic examination, such as proprioceptive deficits, changes in reflexes, and presence of spinal hyperesthesia, are key in identifying neurologic causes of forelimb lameness.

Forelimb Examination, Lameness Assessment, and Kinetic and Kinematic Gait Analysis.

This article contains a guide for small animal practitioners to use when confronted with the challenge of diagnosing a forelimb lameness. The examination begins by monitoring the dog at a stance and a visual gait assessment. A hands-on evaluation includes the initial examination, checking for asymmetry and muscle atrophy while the dog is standing, and step-by-step instructions for a thorough forelimb examination.

An assessment of the effectiveness of hyaluronic acid and polyacrylamide hydrogel in horses with osteoarthritis: Systematic review and network meta-analysis.

For several years, hyaluronic acid (HyA) and, more recently, polyacrylamide hydrogel (PHyd) have been used to reduce lameness and pain caused by osteoarthritis. However, there is still a lack of scientific evidence of the efficacy of these substances to allow veterinary experts to make decisions about their use in horses. The objective of this study was to evaluate, through a systematic review and network meta-analysis (NMA), the efficacy of HyA, associated or not with other drugs, and PHyd in relieving lameness in horses with osteoarthritis. The searches for primary studies were conducted on four search platforms. The efficacy of HyA and PHyd was estimated through the relative risk difference method. Heterogeneity was observed in the efficacy of HyA, indicating long-term ineffectiveness of this drug when associated or not with anti-inflammatory drugs. In contrast, the results indicate that PHyd is an effective alternative therapy, with a long period of action in reducing lameness in horses with osteoarthritis. This study provides evidence that the application of PHyd and HyA is effective in reducing lameness caused by osteoarthritis in horses at different time periods, where PHyd has a longer time of action.

Lameness in dairy cows: farmer perceptions and automated detection technology.

This Research Reflection provides an overview of three interrelated topics: (i) lameness in dairy cows, demonstrating the underpinning importance of the condition, (ii) dairy farmer detection, diagnosis and treatment of lameness and associated foot lesions as well as dairy farmer perceptions towards the condition and (iii) lameness detection technologies, and their potential application on farm to automate the detection of lameness in commercial dairy herds. The presented literature clearly demonstrates that lameness is a major health issue in dairy herds, compromising dairy cow welfare and productivity, and resulting in significant economic implications for dairy farmers. Despite this, dairy farmers fail to perceive lameness as a serious threat to their dairy business. This restricted perception of the importance of lameness may be a product of limited ability to detect lame cows. Many automated lameness detection technologies have been proposed to assist dairy farmers in managing their herds. However, limitations such as cost, performance and dairy farmer perception of the usefulness of these technologies, has lead to poor uptake. It can, therefore, be concluded that there is a need to more thoroughly evaluate the effectiveness of these technologies under on-farm conditions, potentially in the form of a demonstration farm network. This will allow generation of the necessary data required to show dairy farmers that these technologies are reliable and are economically rational for their dairy business.

Association between lameness risk assessment and lameness and foot lesion prevalence on dairy farms in Alberta, Canada.

Lameness is a detrimental health and welfare concern of dairy cattle with high prevalence in North American herds. As a practical and farm-specific approach toward its mitigation in Alberta, Canada, a score-based lameness risk assessment questionnaire (RAQ) was developed for veterinarians to conduct with their clients; however, its accuracy in identifying risk for lameness and hoof lesions has not been evaluated. Our objectives were to (1) provide an update on prevalence of lameness and hoof lesions in Alberta freestall herds, (2) validate the RAQ by determining the association between RAQ scores and the prevalence of herd lameness and herd lesions, and (3) determine the association between presence of common hoof lesions and lameness. For the first 2 objectives, 65 Alberta dairy farms were visited between March and October 2018 to collect a completed RAQ, hoof trimming records from their hoof trimmer, and video footage of the entire lactating herd. For the third objective, 10 participant herds were visited twice between November 2013 and June 2014 to take video footage of the entire lactating herd and collect hoof trimming records from their hoof trimmer within 48 h after video footage collection. Median herd-level lameness prevalence was 20% (range = 2-56%), infectious lesion prevalence was 10% (range = 0-49%), and noninfectious lesion prevalence was 15% (range = 2-39%). Of cows that were lame, 93% had a lesion, whereas 21% of cows with a lesion were lame. Cows with an infectious and noninfectious lesion were, respectively, 1.5 and 3.1 times more likely to be lame than cows with no lesion. Total RAQ score and herd lameness prevalence were correlated (r = 0.26) and noninfectious RAQ score and noninfectious lesion prevalence were correlated (r = 0.45), whereas infectious RAQ score and infectious lesion prevalence were not. Cow-level mixed logistic regression models indicated no associations between any of the RAQ scores and presence of lameness or a hoof lesion. Lameness prevalence in Alberta remains high, indicative of a low adoption rate of mitigation strategies by producers. Improvement of the RAQ could allow for better reflection of lameness and lesions on farm and can be achieved through further risk factor analysis within the RAQ, which may result in removal or addition of questions as well as the adjustment of scores based on risk factors' strength of association with lameness and lesions.