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.

Treatment of Naturally Occurring Tendon Disease with Allogeneic Multipotent Mesenchymal Stromal Cells: A Randomized, Controlled, Triple-Blinded Pilot Study in Horses.

The treatment of tendinopathies with multipotent mesenchymal stromal cells (MSCs) is a promising option in equine and human medicine. However, conclusive clinical evidence is lacking. The purpose of this study was to gain insight into clinical treatment efficacy and to identify suitable outcome measures for larger clinical studies. Fifteen horses with early naturally occurring tendon disease were assigned to intralesional treatment with allogeneic adipose-derived MSCs suspended in serum or with serum alone through block randomization (dosage adapted to lesion size). Clinicians and horse owners remained blinded to the treatment during 12 months (seven horses per group) and 18 months (seven MSC-group and five control-group horses) of follow-up including clinical examinations and diagnostic imaging. Clinical inflammation, lameness, and ultrasonography scores improved more over time in the MSC group. The lameness score difference significantly improved in the MSC group compared with the control group after 6 months. In the MSC group, five out of the seven horses were free of re-injuries and back to training until 12 and 18 months. In the control group, three out of the seven horses were free of re-injuries until 12 months. These results suggest that MSCs are effective for the treatment of early-phase tendon disease and provide a basis for a larger controlled study.

Findings consistent with equine proximal suspensory desmitis can be reliably detected using computed tomography and differ between affected horses and controls.

The objective of this retrospective, observational, controlled study was to evaluate bone and soft tissue window CT images of the proximoplantar metatarsus III region in twenty horses with pain localized to the proximal suspensory ligament (PSL) and 20 horses with findings nonrelated to tarsal pain. All horses underwent CT and radiographic examination. Images were reviewed by three independent observers who graded the severity and localization of findings. Bone-related categories as well as soft tissue-related categories were evaluated. For the comparison of imaging findings in horses with and without proximal suspensory desmitis (PSD), mixed linear regression was performed. The intraclass correlation coefficient (ICC) was calculated to assess intraobserver agreement, and kappa statistics were employed to evaluate interobserver agreement. CT examination identified significantly more abnormalities in the diseased group. The scores for osseous exostosis (p = .015) and PSL enlargement (p = .004) were notably higher in PSD horses compared to controls. Intraobserver agreement was overall high (ICC .82-1.0), and interobserver agreement was substantial for the detection of mineralization (kappa = .61) and moderate for sclerosis (kappa = .43), exostosis (kappa = .43), and PSL enlargement (kappa = .48/.51). Measurements in the soft tissue window were significantly smaller than those in the bone window. Findings concurrent with PSD including osseous proliferation and sclerosis as well as soft tissue enlargement, mineralization, and avulsion can be reliably detected using CT. Findings from the current study supported the use of CT for evaluating horses with suspected PSD where high-field MRI is not available.

A Review on Pathophysiology, and Molecular Mechanisms of Bacterial Chondronecrosis and Osteomyelitis in Commercial Broilers.

Modern day broilers have a great genetic potential to gain heavy bodyweights with a huge metabolic demand prior to their fully mature ages. Moreover, this made the broilers prone to opportunistic pathogens which may enter the locomotory organs under stress causing bacterial chondronecrosis and osteomyelitis (BCO). Such pathogenic colonization is further accelerated by microfractures and clefts that are formed in the bones due to rapid growth rate of the broilers along with ischemia of blood vessels. Furthermore, there are several pathways which alter bone homeostasis like acute phase response, and intrinsic and extrinsic cell death pathways. In contrast, all the affected birds may not exhibit clinical lameness even with the presence of lameness associated factors causing infection. Although Staphylococcus, E. coli, and Enterococcus are considered as common bacterial pathogens involved in BCO, but there exist several other non-culturable bacteria. Any deviation from maintaining a homeostatic environment in the gut might lead to bacterial translocation through blood followed by proliferation of pathogenic bacteria in respective organs including bones. It is important to alleviate dysbiosis of the blood which is analogous to dysbiosis in the gut. This can be achieved by supplementing pro, pre, and synbiotics which helps in providing a eubiotic environment abating the bacterial translocation that was studied to the incidence of BCO. This review focused on potential and novel biomarkers, pathophysiological mechanism, the economic significance of BCO, immune mechanisms, and miscellaneous factors causing BCO. In addition, the role of gut microbiomes along with their diversity and cell culture models from compact bones of chicken in better understanding of BCO were explored.

Expression of genes with biomarker potential identified in skin from DSLD-affected horses increases with age.

Degenerative Suspensory Ligament Desmitis (DSLD) negatively impacts connective tissues in horses, which often leads to progressive chronic pain and lameness. DSLD has been shown to be a systemic disorder that affects multiple body systems, including tendons, sclerae, and the aorta. Currently, the diagnosis is confirmed by post mortem histological examination of a tendon or suspensory ligament. Histology reveals inappropriate accumulations of proteoglycans in the tendons and other tissues in DSLD-affected horses. Unfortunately, there is no reliable method to diagnose DSLD in living horses. Recently, bone morphogenetic protein 2 (BMP2) was identified in active DSLD lesions. In addition, recent data from RNA sequencing (RNA-seq) showed overexpression of numerous genes, among them BMP2, FOS and genes for keratins in DSLD skin biopsies-derived RNA. We hypothesized that some of these genes can be used as biomarkers for diagnosis of DSLD in a panel. Overexpression of some of them was verified in quantitative real time PCR. Immunohistochemistry and RNAscope in-situ hybridization (ISH) assays were used to determine the level of overexpression of specific genes in skin biopsies from control and DSLD-affected horses. The RNAscope ISH assay has shown to be more reliable and more specific that immunohistochemistry. ISH confirmed a significant increase in KRT83 and BMP-2 in hair follicles in DSLD cases, as well as abnormally high expression of FOS in the epidermis, especially in aging horses. Because statistically relevant specificity and sensitivity was documented only for FOS and BMP2, but not KRT83 we recommend the use of FOS and BMP2 panel to diagnose DSLD. We conclude that a panel of two markers from the studied group (BMP2 and FOS) can serve as an additional diagnostic tool for DSLD in living horses, especially in older animals. Further studies are necessary to confirm if this biomarker panel could be used as a prospective tool to identify DSLD in horses as they age.

Pigs' capacity to experience feelings and to suffer from tail lesion, ear lesion and lameness: Exploring citizens and pig farm and abattoir workers' knowledge and perceptions.

The aim of this study was to gain insight into the perceptions of pig farm and abattoir workers as well as lay citizens regarding (1) sentience and (2) positive (intelligent and friendly) and negative (gluttonous, stubborn and dirty) attributes of pigs. We also aimed to investigate the (3) knowledge and perceptions of pig farm and abattoir workers on tail lesion, ear lesion and lameness in pigs and (4) the opinion of lay citizens regarding the likelihood of tail lesions, ear lesions, and lameness causing suffering in pigs and affecting meat quality. Chilean pig farm workers (n = 116), pig abattoir workers (n = 95), and lay citizens (n = 708) were invited on farm, at the abattoir and in public places, respectively, to participate in a survey. Answers were indicated using a 5-point Likert scale (0 = totally disagree; 4 = totally agree). Data were analysed using generalized linear models, including recruitment place and socio-demographic data as predictor variables. Female and lay citizens attributed pigs a higher capacity to experience feelings than male participants and pig farm and abattoir workers (p < 0.05). Lay citizens and workers recruited on farm described pigs as being more intelligent and friendly than those workers recruited at the abattoir (p < 0.001); recruitment place and sex were not associated with participants' perception regarding negative attributes of pigs (p > 0.05). Most lay citizens considered that tail lesions, ear lesions and lameness are likely to cause suffering in pigs and older participants had higher odds of agreeing that tail and ear lesions are likely to affect meat quality (p < 0.05). Finally, the risk factors for tail lesion, ear lesions and lameness pointed out by pig farm and abattoir workers is in line with what has been suggested by experts. Our findings contribute to understand the perception and values of all stakeholders regarding animal welfare, as it is crucial to improve the sustainability of animal production systems.

Proliferative tenosynovitis in Brazilian Mangalarga Marchador horses.

Proliferative tenosynovitis (PT) is an inflammatory and proliferative disorder of the synovial membrane of the tendon sheath that is rare in animals. The histological alterations are characterized by multinodular neovascularization, with infiltration of histiocytic and multinucleated giant cells and haemosiderin deposition. We reviewed necropsy and biopsy records of horses submitted to the Setor de Anatomia Patológica of the Universidade Federal Rural do Rio de Janeiro from January 2017 to December 2020 to select cases of PT. We identified PT in three adult Brazilian Mangalarga Marchador horses with nodular lesions on the metacarpophalangeal, metatarsophalangeal or carpal joints. The three horses were under 6 years of age and presented with lameness and pain on palpation. There were recurrences in two horses after surgical removal. Radiographic and ultrasound examinations detected masses in the flexor or extensor tendons and subtendinous bursa. Histological study of synovial membrane and tendon sheath revealed an increased number of vessels, fibroplasia, osseous metaplasia and infiltration of lymphocytes, plasma cells and siderophages. This is the first description of PT in horses, which should be included as an orthopaedic differential diagnosis, especially in Mangalarga Marchador horses with lameness.

Conservative management of equine tarsal collateral ligament injuries may allow return to normal performance.

OBJECTIVE: To describe type and distribution of tarsal collateral ligament (CL) injuries and to assess the long-term outcome in horses treated conservatively. ANIMALS: 78 horses (median age, 7 years [IQR, 4 to 9.75 years]) of different breeds and disciplines. PROCEDURES: Retrospective analysis (2000 through 2020) of horses with tarsal CL lesions diagnosed on ultrasound. The resting time, ability to return to work, and performance level after the injury were compared between horses having a single ligament (group S) or multiple ligaments (group M) affected and according to the case severity. RESULTS: Most of the horses (57/78) presented a single CL injury, while 21 had multiple CLs affected simultaneously, for a total of 108 CLs injured and 111 lesions. In both groups, the short lateral CL (SLCL) was the most commonly affected (44/108), followed by the long medial CL (LMCL; 27/108). Enthesopathies (72.1%) were more frequent than desmopathies alone (27.9%) and involved mostly the proximal insertion of the SLCL and the distal attachment of the LMCL. Conservative treatment (n = 62) consisted mainly of stall rest. The median resting time (120 days [IQR, 60 to 180 days]) did not significantly differ between the 2 groups (group S vs M) or according to the severity. Most horses (50/62) were able to return to work within 6 months. Horses that did not return (12/62) were more likely to have severe lesions (P = .01). Thirty-eight horses were able to perform at a level equal to or higher than before the injury. CLINICAL RELEVANCE: This study highlights the importance of thorough ultrasound assessment of tarsal CL injuries and demonstrates that conservative management is a viable option to allow these horses to return to previous performance level.

Ultrasonographic comparison of the intermediate patellar ligament in warmbloods versus quarter horses.

Striations are present on ultrasonography of the intermediate (middle) patellar ligament in the transverse plane, which can be confused with tears. Comparison to the contralateral limb is often performed to help differentiate anatomic variation from pathologic change. The purposes of this prospective, observational study were to describe the striation patterns in Warmbloods and Quarter Horses, determine if these patterns are bilaterally symmetrical, and compare striation characteristics between Warmbloods and Quarter Horses. The intermediate patellar ligaments of six Warmblood horses and six Quarter horses, free from clinical signs of hindlimb lameness and in full work, were examined ultrasonographically. Striation pattern, striation number, and the transverse-sectional areas for intermediate patellar ligaments were compared between Warmbloods and Quarter horses. Striation patterns were also compared for the left and right limbs of each horse. A significant difference between breeds was identified at the mid-portion of the intermediate patellar ligament when both left and right ligaments were included (P = 0.02) and when comparing the right intermediate patellar ligament (P = 0.02). There were no other significant breed differences, and a parallel pattern was the most common pattern type. Two-thirds of the horses in this study had bilaterally symmetrical patterns within the distal aspect of their intermediate patellar ligaments, while one-third of the population were asymmetric. These results show that comparison of the contralateral limb during ultrasonography to determine if changes within the distal aspect of the intermediate patellar ligament are normal striations versus tears may lead to misdiagnosis in one-third of horses, regardless of breed. Other signs of pathology on ultrasonography should be used instead.

Retained cartilaginous core in the distal radius of a small breed dog.

A 5-month-old castrated male Smooth Fox Terrier presented for a 1-month history of right thoracic limb lameness. Physical examination revealed right elbow pain on extension and mild soft tissue swelling of the distal antebrachium. Radiographs and computed tomography showed elongated focal radiolucent regions in the distal radial metaphysis. There was incongruity of the right elbow with a short radius. Bone biopsy and histopathology of the regions confirmed a retained cartilaginous core characterised by bony trabeculae with frequently retained central cartilaginous cores. A dynamic proximal ulnar ostectomy was performed to improve elbow congruity. The owner was instructed to restrict activity to short leash walks for 8 weeks followed by a gradual activity increase. On follow-up examination 16 weeks after operatively, the lameness and elbow pain were resolved. Radiographs at that time showed a healed ulnar ostectomy, proper elbow congruity, and resolved retained cartilaginous core.

Comparison of claw horn disruption lesions in four dairy herds using two different trimming techniques: A case study.

Claw disorders are a major problem for health, welfare, and economy in dairy production. This retrospective observational study investigated the association between cow-level prevalence of claw horn disruptive lesions and two different trimming methods - the traditional Danish Method (DAM) and the White Line Atlas Method (WLAM). Trimming records from four herds in Denmark over a 4-year period were analysed. Within each herd, claw trimming was performed with the DAM for the first 2 years, and the WLAM for the next 2 years. The data comprised 3316 claw trimmings of 1027 cows with the WLAM and 3898 claw trimmings of 1080 cows with the DAM. The association between claw trimming method and claw lesions was determined using binominal logistic analysis. There were significant differences between trimming methods for sole haemorrhage (odds ratio = 0.44), sole ulcer (odds ratio = 0.42), and white line separation (odds ratio = 0.64), with a lower prevalence during the period of trimming with the WLAM. No significant difference between trimming methods could be found in the occurrence of white line abscess or double sole. The lower prevalence of claw horn disruption lesions found in this study when cows were trimmed with WLAM justifies and necessitates further experimental studies of claw trimming methods to validate these findings.

[Severe chronic osteomyelitis of the os ileum in an alpaca - Diagnostic and pathological findings]. / Hochgradige chronische Osteomyelitis des Darmbeines bei einem Alpaka.

A 5.5-year-old alpaca mare was referred to the University Clinic for Ruminants due to a lameness in the right hind limb. Six months prior to presentation, the mare had been treated with systemic antibiotics resulting in resolution of the initial lameness. At the time there had been no indication of an inciting trauma. Clinical examination revealed an approx. 2 × 2 cm large, fluctuating, neither excessively warm nor painful mass caudal to the right tuber coxae fixed to the underlying tissue. In addition, a moderate, mixed lameness with a predominant proportion of the swinging leg component was present in the right hind limb. Subsequently, sonographic examination of the right gluteal region was performed, revealing severe alterations of bone contour in the area of the right hip joint. Radiographic assessment of the pelvis was carried out for further clarification. Based on the clinical finding of a fistula in the right gluteal region as well as the results of the radiologic examination, a long-standing infected fracture of the right iliac bone accompanied by high-degree, irregularly calcified callus formation and low to moderate osteomyelitis in the fracture area was diagnosed. The patient was euthanized in consequence of the grave prognosis. Computed tomographic examination of the pelvis and the lumbar spine in the L3-L6 area was undertaken in order to further document the extent of the pathological changes. For final clarification, patho-histological examination as well as a microbiologic analysis of the abscess exudate were performed.The presented case shows the importance of clinical as well as orthopedic examinations, as the individual animal frequently only exhibits minimal clinical signs despite the presence of severe changes.

Denervating the pelvic suspensory ligaments of horses causes morphological and histological changes in the ligaments.

OBJECTIVE: To examine changes occurring in normal pelvic suspensory ligaments (SLs) of horses after denervating these ligaments and to investigate the effect chronic inflammation might have on these changes. ANIMALS: 10 horses. PROCEDURES: The SL of 1 randomly selected pelvic limb of each of 5 horses was injected with collagenase to induce desmitis, and 42 days later, the proximal aspect of both pelvic SLs were denervated. The SLs were harvested 120 days after being denervated, and the morphological and histological characteristics of each collagenase-injected, denervated SL were compared with those of the contralateral, non-injected, denervated SL. All denervated SLs were compared with non-denervated pelvic SLs harvested from 5 horses similar in weight and age. RESULTS: The mean width and the cross-sectional area of the musculature of all denervated SLs were significantly less than that of the non-denervated ligaments. The mean thickness of collagenase-injected denervated ligaments, but not that of the non-injected denervated ligaments, was significantly less than that of the non-denervated ligaments. Histological abnormalities typical of neurogenic muscular atrophy were observed in all denervated ligaments. CLINICAL RELEVANCE: Loss of motor neuronal input to the proximal aspect of the SL of the pelvic limb of horses causes neurogenic atrophy of the musculature in that portion of the ligament. Denervating a SL of a pelvic limb may weaken the ligament, increasing its risk of injury. Chronic inflammation of the SL before neurectomy may exacerbate atrophy of the musculature after neurectomy.

Recombinant fibroblast growth factor-18 (sprifermin) enhances microfracture-induced cartilage healing.

Posttraumatic osteoarthritis is a disabling condition impacting the mostly young and active population. In the present study, we investigated the impact of intra-articular sprifermin, a recombinant truncated fibroblast growth factor 18, on the outcome of microfracture treatment, a widely used surgical technique to enhance cartilage healing at the site of injury. For this study, we created a cartilage defect and performed microfracture treatment in fetlock joints of 18 horses, treated joints with one of three doses of sprifermin (10, 30, or 100 µg) or with saline, hyaluronan, and evaluated animals functional and structural outcomes over 24 weeks. For primary outcome measures, we performed histological evaluations and gene expression analysis of aggrecan, collagen types I and II, and cartilage oligomeric matrix protein in three regions of interest. As secondary outcome measures, we examined animals' lameness, performed arthroscopic, radiographic, and computed tomography (CT) scan imaging and gross morphology assessment. We detected the highest treatment benefit following 100 µg sprifermin treatment. The overall histological assessment showed an improvement in the kissing region, and the expression of constitutive genes showed a concentration-dependent enhancement, especially in the peri-lesion area. We detected a significant improvement in lameness scores, arthroscopic evaluations, radiography, and CT scans following sprifermin treatment when results from three dose-treatment groups were combined. Our results demonstrated, for the first time, an enhancement on microfracture outcomes following sprifermin treatment suggesting a cartilage regenerative role and a potential benefit of sprifermin treatment in early cartilage injuries.

Aged Tmem106b knockout mice display gait deficits in coincidence with Purkinje cell loss and only limited signs of non-motor dysfunction.

Genetic variants in TMEM106B are a major risk factor for several neurodegenerative diseases including frontotemporal degeneration, limbic-predominant age-related TDP-43 encephalopathy, Parkinson's disease, late-onset-Alzheimer's disease and constitute a genetic determinant of differential aging. TMEM106B encodes an integral lysosomal membrane protein but its precise physiological function in the central nervous system remains enigmatic. Presently, we aimed to increase understanding of TMEM106B contribution to general brain function and aging. We analyzed an aged cohort of Tmem106b knockout-, heterozygote and wild-type mice in a behavioral test battery including assessments of motor function as well as, social, emotional and cognitive function. Aged Tmem106b knockout (KO) mice displayed diverse behavioral deficits including motor impairment, gait defects and reduced startle reactivity. In contrast, no prominent deficits were observed in social, emotional or cognitive behaviors. Histologically, we observed late-onset loss of Purkinje cells followed by reactive gliosis in the cerebellum, which likely contributed to progressive decline in motor function and gait defects in particular. Reactive gliosis was not restricted to the cerebellum but observed in different areas of the brain including the brain stem and parts of the cerebral cortex. Surviving Purkinje cells showed vacuolated lysosomes in the axon initial segment, implicating TMEM106B-dependent lysosomal trafficking defects as the underlying cause of axonal and more general neuronal dysfunction contributing to behavioral impairments. Our experiments help to elucidate how TMEM106B affects spatial neuronal homeostasis and exemplifies a critical role of TMEM106B in neuronal cells for survival.

Relationships between type of hoof lesion and behavioral signs of lameness in Holstein cows housed in Canadian tiestall facilities.

Although foot pain can affect gait, the presence of a hoof lesion may or may not cause the cow to show visible changes in their gait. This can be dependent on the type and severity of the lesion; for example, the presence of a sole ulcer (SU) has been associated with increased gait scores, whereas digital dermatitis (DD) and sole hemorrhage (SH) have not. In tiestall facilities, gait scoring can be difficult to perform. An alternative method, known as stall lameness scoring (SLS), allows observers to assess cattle for lameness while they remain in their stall. Lameness is determined based on behavioral changes in weight bearing and foot positioning, which include: shifting weight, resting a foot, standing on the edge of the stall, and uneven weight bearing when stepping side to side. The aim of this study was to examine relationships between hoof lesions and these behavioral indicators. A total of 557 observations of SLS and corresponding hoof trimming records, collected during routine trimming events on 7 tiestall herds, were obtained. Trimming was performed by 2 trained hoof trimmers with good agreement on lesion identification, based on quizzes taken at the beginning and mid-way through the study. To ensure trimming had no effect on the behavioral indicators observed, SLS was always performed by a trained observer before trimming. Behavioral indicators focused on the hind limbs only; therefore, the analysis was confined to hind limb lesions using logistic regression to detect the presence of hoof lesion based on observations made during SLS. Seventy-five percent of observed cows had no SLS behavioral indicators, whereas, 11, 12, and 1% had 1, 2, and 3 behavioral indicators, respectively. At least one hind limb lesion was noted during trimming in 19% of cows, with the most common lesions being DD (7%), SU (6%), and SH (4%). A cow that was observed resting one foot and bearing weight unevenly when moving side to side had higher odds of having a hind limb hoof lesion than a cow not displaying these behaviors. When looking at specific hoof lesions, a cow observed resting one limb and bearing weight unevenly had higher odds of having a SU compared with those not displaying these behaviors. A cow observed shifting their weight from one foot to another had higher odds of having SH, and a cow observed bearing weight unevenly had higher odds of DD. Behavioral indicators in weight bearing and foot positioning can help identify cows in tiestalls with hind limb hoof lesions. Producers could routinely observe their cattle for these indicators to assist in the identification of cows that may require treatment. This could help reduce the duration of clinical lameness through earlier intervention.

Analysis of a Laxity Index Database and Comparison with the Fédération Cynologique Internationale Grades of This Population.

OBJECTIVE: This study aimed to analyse the distribution of the laxity indices (LI) in a dog population, to compare the LI with the Fédération Cynologique Internationale (FCI) grades and to search for differences of LI between breeds. STUDY DESIGN: The database was composed of all dogs presented to the University Hospital of the Faculty of Veterinary Medicine in Ghent for obligatory hip screening between January 2016 and February 2019, and all patients presented to orthopaedic consultation between January 2017 and January 2019 for a complaint of hindlimb lameness, which underwent both a standard extended ventrodorsal radiograph of the hips and a stress radiograph revealing hip joint laxity. The latter was obtained by means of the Vezzoni-modified Badertscher distension device and the LI was calculated. For each dog of the population, the LI was then compared with the FCI grade. RESULTS: The LI values ranged between 0.15 and 1.04, with a mean of 0.46. The LI and the FCI grade increased together, and showed a moderate-to-good correlation. There was a highly significant overall difference in the mean value of LI per FCI grade group (p < 0.001). The mean LI of the Labrador Retrievers was slightly but significantly lower than the mean LI of the Golden Retrievers (p < 0.01). CONCLUSION: The LI calculated on a stress radiograph taken with the Vezzoni-modified Badertscher distension device shows a good correlation with the FCI grade assigned on a standard extended ventrodorsal projection. A wide range of passive hip joint laxity exists in dogs considered to be phenotypically normal based on the FCI grading method.

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.

Short communication: Accuracy of estimation of lameness, injury, and cleanliness prevalence by dairy farmers and veterinarians.

Lameness, injuries, and cleanliness are considered important indicators of dairy cow welfare, milk production, and milk quality. Previous research has identified that farmers globally underestimate the prevalence of these cow-based measurements, but no information on the perceptions of veterinarians is available. Because veterinarians are often perceived as the main providers of health advice on farms, the objective of the present study was to evaluate the relationship between the true prevalence of lameness, injury (hock, knee, neck), and cleanliness (udder, legs, flanks), and the estimated prevalence of these issues by farmers and their herd veterinarians. A cross-sectional study was conducted between February 2016 and July 2017. First, the farm owner and the herd veterinarian were asked to estimate the prevalence of lameness, of neck, knee and hock injuries, and of udder, leg, and flank cleanliness on the farm. The research team then visited the farm and scored all lactating cows in the herd for each measurement. Linear regression models were used to assess the relationship between the prevalence estimated by the veterinarians and the farmers, of each cow-based measurement, and the true prevalence on the farm. The 93 herds enrolled had a median of 55 milking cows and were housed in tiestall (90%) and freestall (10%) barns. Ten herd veterinarians participated and were involved with 2 to 22 enrolled farms each. A wide variation was detected in the true prevalence of the different cow-based measurements among herds (lameness: range = 19-72%, median = 36%; neck injuries: range = 0-65%, median = 14%; knee injuries: range = 0-44%, median = 12%; hock injuries: range = 0-57%, median = 25%; dirty udder: range = 0-55%, median 13%; dirty legs: range = 0-91%, median = 18%; and dirty flanks: range = 0-82%, median = 20%). For both veterinarians and farmers, the perception of each cow-based measurement prevalence increased incrementally as the herd's true prevalence increased. Overall, farmers and veterinarians underestimated cow-based measurements. Farmers and veterinarians more accurately estimated lameness prevalence in herds with higher prevalence than in herds with low prevalence, suggesting a better awareness of the issue on farms with lameness problems. Injuries were less accurately estimated in herds with higher injury prevalence compared with herds with lower prevalence, suggesting an opportunity for better knowledge transfer in this area.

In vitro biomechanical properties of sole tissues: Comparison between healthy and ulcerated bovine claws.

Sole ulcers are reportedly one of the most prevalent diseases associated with lameness in dairy cattle, significantly affecting animal welfare and farm profitability. The degree to which sole soft tissues, healthy or ulcerated, are able to maintain their structure and function when subjected to compressive forces remains unknown. Therefore, the aims of the present study were to assess sole tissue biomechanics in healthy and ulcerated claws and to describe correlated histology. Cylindrical samples were harvested from zones 4 and 6, as described by the international foot map, from hind lateral healthy (n = 12) and ulcerated bovine claws (n = 8; animals n = 12). Tissue biomechanics and morphology were evaluated via compressive tests and hematoxylin-eosin-phloxine-saffron staining, respectively. A 2-sample t-test was used to compare zones' mechanical properties between healthy and ulcerated tissues, and the Cochran-Mantel-Haenszel test was used to measure the effect of claw zone on histology. The fibril modulus (Ef) and permeability (k) respectively increased and decreased in ulcerated claws (Ef = 0.201 ± 0.104 MPa; k = 0.128 ± 0.069 mm2/MPa·s) compared with healthy claws (Ef = 0.105 ± 0.050 MPa; k = 0.452 ± 0.365 mm2/MPa·s) only for zone 6. Histology scores equal to or greater than 3 were associated with macroscopic presence of ulceration. A higher proportion of adipose tissue (30% or more) was associated with zone 6 compared with zone 4, but no difference was seen between healthy and ulcerated claws. Ulcerated claws had a higher prevalence of exostoses compared with healthy ones (33% vs. 8%). Sole soft tissues showed, as hypothesized, a viscoelastic behavior using unconfined compression testing, which, however, may not reflect in vivo loading conditions. Clinical and histological signs of sole ulceration were not associated with decreased strength of the supportive apparatus of the distal phalanx in zone 4 in this study.