Evaluating the impact of application of anaerobic bacterial fermentation enhancer on digital dermatitis.

The control of digital dermatitis (DD) among cattle is crucial; however, effective and environmentally-sound control measures have yet to be identified. From the monitoring data of DD which were recorded during regular hoof trimmings in a farm in Hokkaido, Japan, we detected a decrease in the DD prevalence in a herd where an anaerobic bacterial fermentation enhancer (ABFE) was distributed. The possible effect of ABFE was analyzed using a retrospective repeated cross-sectional design. The prevalence of DD decreased over time in the ABFE-distributed group. Furthermore, a selected regression model indicated the time-dependent enhancement of the decreasing trend. While potential coincidental factors may influence, this study provides a basis for further research on the preventive effect of ABFE against DD.

Bovine Digital Dermatitis: Treponema spp. on trimming equipment and chutes - effect of washing and disinfection.

BACKGROUND: Digital dermatitis (DD) is a contagious bovine foot disease causing reduced animal welfare and negative economic consequences for the farmer. Treponema spp. are the most important causative agents. Studies indicate that trimming equipment can transfer DD-associated treponemes between cows. The aim of this observational study in 22 DD-positive Norwegian dairy herds was to investigate the risk of transferring Treponema spp. with trimming equipment and chutes after claw trimming, and after washing and disinfection. Swabs from the trimming equipment and chutes were collected from nine different locations, at five different time points. Bacterial DNA was extracted from 647 swabs and analysed by qPCR for Treponema spp. In addition, 172 swabs taken immediately after trimming, were analysed by a multiplex qPCR targeting T. phagedenis, T. pedis and T. medium/vincentii. Biopsy sampling from DD lesions was performed on cows in the same herds during trimming. Altogether 109 biopsies were analysed by FISH for confirmation of the DD diagnosis and identification of Treponema phylotypes (PTs). RESULTS: High numbers of Treponema spp. were detected from all nine locations on the trimming equipment and chutes immediately after trimming, and T. phagedenis was detected on two or more locations in all but two herds, 1 and 19. There was a decline in the amount of Treponema spp. after washing and disinfection. The belly belt, the cuff, and the footrest on the chute had the highest proportion of positive samples after disinfection. The belly belt had the highest copy numbers of all nine locations (median = 7.9, max = 545.1). No Treponema spp. was detected on the hoof knives after disinfection. Treponema phagedenis, T. pedis, and Treponema phylotype 3 (T. refringens) were detected by FISH analysis of the biopsies. Treponema phagedenis was detected in biopsies from all herds except 1 and 19. CONCLUSION: This study shows that DD-associated Treponema spp. were present on the trimming equipment and chutes after trimming cows in DD-positive herds. Washing and disinfection reduced the load of Treponema spp. However, large differences in Treponema spp. between different locations were documented. High copy numbers on the grinder and the chute after disinfection, indicates that sufficient cleaning and disinfection of these locations is difficult, and that passive transfer of DD-associated treponemes (viable or not) is possible.

Surgical excision of P3 fragments in 86 declawed cats: case series (2013-2023).

CASE SERIES SUMMARY: This case series describes the clinical findings and surgical intervention of 86 declawed cats; 52 from a shelter or rescue and 34 owned cats. Historical reports from owners and shelter staff included house-soiling, biting behavior, repelling behavior, barbering, lameness, chronic digit infection and nail regrowth. All the cats had fragments of the third phalanx (P3) of varying sizes diagnosed on radiographs. Pathology visible on examination included digital subcutaneous swelling, ecchymosis, malaligned digital pads, ulcerations, exudate, tendon contracture, nail regrowth and callusing. Surgery was pursued in these cases to remove the P3 fragments, relieve tendon contracture and reposition the digital pads with an anchoring suture. Gross findings intraoperatively included fragmented growth of cornified and non-cornified nail tissue, osteophytes on the surface of the second phalanx, deep digital flexor tendon calcification, and both bacterial and sterile exudate. The most common complication 14 days postoperatively was mild (14%) to moderate (1%) lameness. All historical parameters recorded improved in both populations of cats (house-soiling, biting behavior, repelling behavior, barbering, lameness, tendon contracture and chronic digit infection). Postoperatively, 1/47 cats exhibited continued malalignment of two digital pads and there were no reports of long-term postoperative lameness. RELEVANCE AND NOVEL INFORMATION: Two methods of declawing cats are detailed in the veterinary literature, including partial amputation of P3 and disarticulation of the entire P3 bone. The novel information in this report includes historical and clinical signs of declawed cats with P3 fragments, intraoperative gross pathology, surgical intervention and the postoperative follow-up results.

Uncommon dermatologic manifestation (paronychia) in a cat with diabetes mellitus.

A 3.5-year-old male intact domestic short hair cat presented for a chronic wound and crusts over the claw and claw folds over several months. The cat was diagnosed with diabetes mellitus based on the presence of persistent hyperglycemia, glucosuria, and compatible clinical signs which consist of polyuria, polydipsia, polyphagia, and weight loss. Glipizide (Glucotrol XL, Pfizer, Indonesia) 2.5 mg orally twice daily was prescribed. By the seventeenth day, the patient's claws and skin around the paw had normalized and the abnormal claw sloughed off, revealing a normal claw underneath. Blood glucose, urinalysis and serum fructosamine were also normalized by the thirtieth day. The patient underwent diabetic remission, and the skin and claw lesions have remained in remission and not recurred since the treatment of the diabetes mellitus. This is the first report of a diabetic cat with dermatologic changes to the skin and claw regions. As the diabetes mellitus went into clinical remission, so too did the dermatologic manifestations, even without any specific dermatologic treatment.

Association between a genetic index for digital dermatitis resistance and the presence of digital dermatitis, heel horn erosion, and interdigital hyperplasia in Holstein cows.

Digital dermatitis (DD) is a polybacterial disease endemic to most UK dairy farms. It poses a major financial and welfare threat and is characterized by high incidence and recurrence rates. We aimed to investigate the association between the UK EBV for resistance to digital dermatitis, the digital dermatitis index (DDI), and the frequency of DD, heel horn erosion (HHE), and interdigital hyperplasia (IH) in a population of Holstein dairy cows. We enrolled and genotyped 2,352 cows from 4 farms in a prospective cohort study. Foot lesion records were recorded by veterinary surgeons for each animal at 4 time points during a production cycle, starting at approximately 2 mo before calving and ending in late lactation. Importantly, these records were not used in the calculation of the DDI. Lesion records were matched to the animal's own DDI (n = 2,101) and their sire's DDI (n = 1,812). Digital dermatitis index values in our study population ranged from -1.41 to +1.2 and were transformed to represent distance from the mean expressed in SD. The relationship between the DDI and the presence of DD was investigated using a logistic regression model, with farm, parity, and a farm-parity interaction fitted as covariates. A multivariable logistic regression model was fitted to evaluate the relationship between HHE and DDI with farm fitted as a covariate. Finally, a univariable logistic regression model with DDI as explanatory variable was used to investigate the relationship between IH and DDI. The odds ratio of an animal being affected by DD was 0.69 for 1 SD increase in the animal's DDI (95% CI = 0.63-0.76). The odds of HHE and IH were 0.69 (95% CI = 0.62-0.76) and 0.58 (95% CI = 0.49-0.68) respectively for 1 SD increase in DDI. The adjusted probability of DD was 32% (95% CI = 27-36%) for cows with mean DDI value of 0, while it was 24% (95% CI = 20-29%) in cows with a DDI value of +1. Sire DDI breeding values were standardized in the same way and then binned into terciles creating an ordinal variable representing bulls of high, medium, and low genetic merit for DD resistance. The daughters of low genetic merit bulls were at 2.05 (95% CI = 1.60-2.64), 1.96 (95% CI = 1.53-2.50), and 2.85 (95% CI = 1.64-5.16) times greater odds of being affected by DD, HHE, and IH, respectively, compared with the daughters of high genetic merit bulls. The results of this study highlight the potential of digital dermatitis genetic indexes to aid herd management of DD, and suggest that breeding for resistance to DD, alongside environmental and management control practices, could reduce the prevalence of the disease.

Evaluation of potassium monopersulfate footbath solution for controlling digital dermatitis in lactating dairy cattle. A randomized clinical trial.

Our objective was to assess potassium monopersulfate as a disinfectant used in footbath to control digital dermatitis (DD) in dairy cows. We hypothesized that a potassium monopersulfate solution would control DD. A 180-day randomized negative controlled trial was conducted in a 265-Holstein free-stall facility. Throughout the trial, foot bathing was performed bi-weekly using a split (left vs. right feet) footbath: one tub filled with 1% potassium monopersulfate (treatment), the other with tap water (control). Digital dermatitis lesions were scored during trimming chute examinations of the unwashed hind heels every 90 days using the modified M-scoring system. Digital dermatitis lesions were re-categorized into four variables: 1) inactive; 2) active; 3) any; 4) inactive or absence of DD lesions. Three longitudinal outcomes were characterized: risks of 1) developing a DD lesion; 2) reactivating an inactive DD lesion; 3) development of an inactive or the absence of the DD lesion. A generalized linear model was used to compare the variables and longitudinal outcomes between treated and control groups. Prevalence of active DD lesions increased from 12.5% to 39.9% between days 0 and 90. This significant increase in prevalence justified the discontinuation of the study on day 90 for ethical reasons. There was no statistical difference between treated and control groups for the first outcome (RR: 1.0; 95% CI: 0.62, 1.7), the second outcome (RR: 1.0; 95% CI: 0.62,-1.7); or the third outcome (RR: 0.88; 95% CI: 0.37, 2.1). A 1% potassium monopersulfate footbath solution appears ineffective to control DD in this study.

Genome-wide association and functional genomic analyses for various hoof health traits in North American Holstein cattle.

Hoof diseases are a major welfare and economic issue in the global dairy cattle production industry, which can be minimized through improved management and breeding practices. Optimal genetic improvement of hoof health could benefit from a deep understanding of the genetic background and biological underpinning of indicators of hoof health. Therefore, the primary objectives of this study were to perform genome-wide association studies, using imputed high-density genetic markers data from North American Holstein cattle, for 8 hoof-related traits: digital dermatitis, sole ulcer, sole hemorrhage, white line lesion, heel horn erosion, interdigital dermatitis, interdigital hyperplasia, and toe ulcer, and a hoof health index. De-regressed estimated breeding values from 25,580 Holstein animals were used as pseudo-phenotypes for the association analyses. The genomic quality control, genotype phasing, and genotype imputation were performed using the PLINK (version 1.9), Eagle (version 2.4.1), and Minimac4 software, respectively. The functional genomic analyses were performed using the GALLO R package and the DAVID platform. We identified 22, 34, 14, 22, 28, 33, 24, 43, and 15 significant markers for digital dermatitis, heel horn erosion, interdigital dermatitis, interdigital hyperplasia, sole hemorrhage, sole ulcer, toe ulcer, white line lesion disease, and the hoof health index, respectively. The significant markers were located across all autosomes, except BTA10, BTA12, BTA20, BTA26, BTA27, and BTA28. Moreover, the genomic regions identified overlap with various previously reported quantitative trait loci for exterior, health, meat and carcass, milk, production, and reproduction traits. The enrichment analyses identified 44 significant gene ontology terms. These enriched genomic regions harbor various candidate genes previously associated with bone development, metabolism, and infectious and immunological diseases. These findings indicate that hoof health traits are highly polygenic and influenced by a wide range of biological processes.

Ex vivo biomechanical evaluation of an adhered fiberglass and polymethyl methacrylate sole-hoof wall cast on stabilization of type III distal phalanx fractures under simulated physiologic midstance loads.

OBJECTIVE: To evaluate the effect of the application of a novel fiberglass-glue cast (FGC) on the fracture gap width in experimentally created type III distal phalanx fractures in cadaveric specimens under simulated physiologic loads. STUDY DESIGN: Ex vivo biomechanical laboratory study. ANIMALS: Nine unilateral adult equine cadaver forelimbs. METHODS: Type III distal phalanx fractures were created in forelimb specimens, which maintained distal components of the passive stay apparatus. The fracture gap was measured at 5%, 20%, 25%, 50%, 75%, and 95% of fracture length (palmar articular border to solar margin) using D65Pr-PaDiO radiographs. The limb was axially loaded (700, 3600, 4600, and 6700 N) before, during, and after removal of a woven fiberglass cloth and polymethyl methacrylate cast that encompassed the sole and distal portion of the hoof wall (FGC). Fracture gap widths were compared among loads and treatments using a mixed model ANOVA. RESULTS: On average, under simulated physiological midstance loads, the fracture gap width was 0.2 mm smaller after FGC application, with the greatest decrease (0.5 mm) near the articular surface. On average, it was 0.3 mm smaller than after FGC removal. Fracture gap width was 0.1 mm greater when midstance loads transitioned from standing load to walking, trotting, and gallop loads. The fracture gap width increased by 1.3 mm with increasing distance from the articular surface. CONCLUSION: The FGC reduced the fracture gap width and prevented the fracture gap widening that occurred after FGC removal. CLINICAL SIGNIFICANCE: The findings support consideration of FGC use in the treatment of horses with type III distal phalangeal fractures.

Routine hoof-trimming data provides insight into the occurrence of claw lesions in Holstein herds in the central region of South Africa.

Claw lesions in dairy cows contribute significantly to lameness, causing distress and discomfort for affected cows and raising welfare concerns. Despite increased awareness, lameness incidence continues to rise. Defining and recording claw traits are particularly problematic. In South Africa (SA), claw data is limited to paper-based records kept by private hoof trimmers. This research analysed claw-trimming data from five dairy farms over 6 years to examine the occurrence and recording of claw lesions in SA Holstein cattle. Lesion identification followed the Claw Lesion Identification in Dairy Cattle brochure. Among the recorded lesions, digital dermatitis (DD) had the highest prevalence (64.02%), followed by sole ulcers (SU; 8.59%), white line disease (WLD; 6.27%), and sole haemorrhage (SH; 4.28%), and most lesions occurred in the rear feet. Chi-square tests and correspondence analysis (CA) were employed to explore the relationships between lesions, feet, and housing. Results indicated that the prevalence of SU and SH showed high similarity for foot and lesion association, and that these were more highly associated with the rear feet. Additionally, the prevalence of DD and interdigital phlegmon were strongly associated, and closely associated with SU, and all these lesions were associated with both dirt lot and free-stall housing systems. CA further confirmed a close association between WLD and SH, and the prevalence of these lesions in the combination housing system. Results of this study highlight the complexity of lesion data and that specific associations between lesions could lead to simplifying the recording thereof. Consolidating the most informative claw lesions into categories will aid in the practical prevention, management, and treatment of lameness on-farm.

Chemical composition of horse hooves with functional qualities for competing barefoot.

Barefoot racing is a common practice within the harness racing industry, but not all horses have hooves of sufficient quality to race sustainably without shoes. There is currently no objective approach available to assess whether a horse's hooves are suitable for barefoot racing, raising animal welfare issues if trainers misjudge the functional qualities of hooves. This study compared chemical composition of the hoof wall and fatty acid (FA) composition of the digital cushion in a group of horses that had raced barefoot often (RB) and a group of horses that could not race barefoot and therefore raced with shoes (RS). Trimmings from the hind hoof wall were collected from the lateral quarters in one sub-cohort postmortem and in another sub-cohort of live horses and analyzed for macro- and microelements, nitrogen, dry matter (DM), and total and free amino acid content. For the postmortem horses, samples of the digital cushion were also collected and analyzed for total and free FAs. RB horses had lower concentrations of copper in the hoof wall (17.5 ±â€…3.9 vs. 32.8 ±â€…4.7 mg/kg DM, P = 0.02) than RS horses. RB horses also tended (P < 0.1) to have higher concentrations of nitrogen (164.2 ±â€…0.2 vs. 163.5 ±â€…0.3 g/kg DM) and sulfur (22.9 ±â€…0.2 vs. 22.3 ±â€…0.3 g/kg DM). RB horses had higher hoof wall concentrations of arginine (10.51 ±â€…0.05 vs. 10.34 ±â€…0.06 g/100 g DM, P = 0.03) and showed a trend (P < 0.1) for higher hoof wall concentrations of cysteine (6.14 ±â€…0.10 vs. 5.82 ±â€…0.13 g/100 g DM) and proline (4.62 ±â€…0.05 vs. 4.49 ±â€…0.06 g/100 g DM). There were no differences between the groups for any other element or amino acid analyzed. There were also no differences between the two groups in terms of FA composition of the digital cushion. These results indicate that chemical composition, especially with respect to copper, arginine, nitrogen, sulfur, cysteine, and proline, may be important for the functional qualities of the hoof capsule and the ability to race barefoot without wearing the hoof down. However, chemical analysis of hoof wall tissue and of the fat content of the digital cushion does not seem to be a definitive method for distinguishing horses that have hooves suitable for barefoot racing from those that do not.

Barefoot racing is a common practice within the harness racing industry, as it may make a horse run faster. However, not all horses have hooves of sufficient quality to withstand the wear from the track surface during racing, creating a risk of hoof damage. Therefore, an objective method is needed to distinguish between horses that have hooves suitable for barefoot racing and those that do not. In this study, we compared the chemical composition of hoof walls and the fatty acid (FA) composition of the digital cushion in horses that had raced barefoot often and horses that could not race barefoot frequently. We found differences between the two groups of horses in terms of mineral- and amino acid concentrations in the hoof wall, but not in the FA composition of the digital cushion. This indicates that chemical composition may be important for the functional qualities of the hoof capsule and the ability to race barefoot without hoof wear and damage. However, chemical analysis of hooves is not a definitive method for distinguishing horses suitable for barefoot racing from horses that are not suitable.

Transmission and lesion progression of treponeme-associated hoof disease in captive elk (Cervus canadensis).

Treponeme-associated hoof disease (TAHD) is a debilitating disease of free-ranging elk (Cervus canadensis) in the northwestern U.S. While treponemes are associated with lesions, the etiology and transmissibility between elk are unknown. Our objective was to determine whether the disease can be environmentally transmitted to captive elk. Four individually housed treatment elk and 2 control elk were challenged with soil mixed with inoculum prepared from free-ranging elk hooves from TAHD-positive elk or autoclaved hooves from normal elk, respectively. The inoculum for each group was applied to the interdigital space and added to pre-existing soil in each pen. Eight challenges were conducted at 1-4-week intervals and lesion development was assessed during a 138-day challenge period that was followed by a 170-day monitoring period to document lesion progression. All treatment elk, but no control elk, developed gross and histologic lesions consistent with TAHD. Treponema phylotypes similar to those in bovine digital dermatitis in cattle were detected using 16S rRNA gene amplicon sequencing from lesions in all treatment elk, but no control elk, during the challenge period. Lesions progressed from ulcerations in the interdigital space to extensive ulceration and underrunning of the hoof capsule by 35 and 173 days following the initial inoculation, respectively. Lameness in treatment elk was correlated with lesion development (R = 0.702, p≤0.001), and activity of infected elk was reduced during the challenge (p≤0.001) and monitoring periods (p = 0.004). Body condition was significantly lower in treatment than control elk 168 days following the initial inoculation (p = 0.05) and at each individual elk's study endpoint (p = 0.006). Three of 4 treatment elk were euthanized when they reached humane endpoints, and one elk recovered. These results provide direct evidence that TAHD is a transmissible infectious disease in elk. As such, actions that reduce transmission risk can support disease management and prevention.

Equine Hoof Progenitor Cells Display Increased Mitochondrial Metabolism and Adaptive Potential to a Highly Pro-Inflammatory Microenvironment.

Medicinal signaling cells (MSC) exhibit distinct molecular signatures and biological abilities, depending on the type of tissue they originate from. Recently, we isolated and described a new population of stem cells residing in the coronary corium, equine hoof progenitor cells (HPCs), which could be a new promising cell pool for the treatment of laminitis. Therefore, this study aimed to compare native populations of HPCs to well-established adipose-derived stem cells (ASCs) in standard culture conditions and in a pro-inflammatory milieu to mimic a laminitis condition. ASCs and HPCs were either cultured in standard conditions or subjected to priming with a cytokines cocktail mixture. The cells were harvested and analyzed for expression of key markers for phenotype, mitochondrial metabolism, oxidative stress, apoptosis, and immunomodulation using RT-qPCR. The morphology and migration were assessed based on fluorescent staining. Microcapillary cytometry analyses were performed to assess the distribution in the cell cycle, mitochondrial membrane potential, and oxidative stress. Native HPCs exhibited a similar morphology to ASCs, but a different phenotype. The HPCs possessed lower migration capacity and distinct distribution across cell cycle phases. Native HPCs were characterized by different mitochondrial dynamics and oxidative stress levels. Under standard culture conditions, HPCs displayed different expression patterns of apoptotic and immunomodulatory markers than ASCs, as well as distinct miRNA expression. Interestingly, after priming with the cytokines cocktail mixture, HPCs exhibited different mitochondrial dynamics than ASCs; however, the apoptosis and immunomodulatory marker expression was similar in both populations. Native ASCs and HPCs exhibited different baseline expressions of markers involved in mitochondrial dynamics, the oxidative stress response, apoptosis and inflammation. When exposed to a pro-inflammatory microenvironment, ASCs and HPCs differed in the expression of mitochondrial condition markers and chosen miRNAs.

[Implementation of biosecurity measures by hoof trimmers in Switzerland]. / Umsetzung von Biosicherheitsmassnahmen durch Klauenpfleger in der Schweiz.

INTRODUCTION: Biosecurity in livestock farming includes all measures preventing pathogen introduction onto a farm (external biosecurity) and pathogen transmission on the farm itself (internal biosecurity). An important risk factor for the dissemination of infectious diseases are specialised external persons working on numerous farms, such as professional hoof trimmers in Switzerland. In the present study, 49 hoof trimmers, participating in the Swiss claw health programme and working as professionals, were questioned regarding their biosecurity measures and observed by two veterinarians during hoof trimming in order to assess the implementation of biosecurity measures by hoof trimmers. Data were processed using a scoring system, in which points were allocated to the different working methods taking into account their assumed transmission potential for infectious diseases such as digital dermatitis (DD) and Salmonellosis. The working method, which complied with the ideal biosecurity measure, was always given a whole point, whereas less optimal working methods were only given an intermediate value or no point. The scoring system helped identify precisely the strengths and weaknesses of the hoof trimmers in terms of biosecurity. The level of implementation of biosecurity measures by hoof trimmers was overall quite low (53 %=average of the overall biosecurity scores of the 49 hoof trimmers). Hoof trimmers which attended specialised training courses tended to have a higher level of implementation of biosecurity measures. The answers given by the hoof trimmers and the observations made by the veterinarians were compared, whereby it was found that hoof trimmers generally evaluated themselves better in regard to biosecurity than veterinarians assessed them. In summary and based on the results of this study, the dissemination of pathogens, such as DD associated treponemes and salmonella is possible during hoof trimming performed by external persons working on numerous farms. Thus, future training and continuing education courses should place emphasis on biosecurity.

INTRODUCTION: Le concept de biosécurité englobe, en lien avec la production animale, toutes les mesures empêchant l'introduction de germes dans une exploitation (biosécurité externe) et la propagation de germes à l'intérieur de l'exploitation (biosécurité interne). Un facteur de risque important pour la propagation de maladies infectieuses est le personnel spécialisé externe travaillant sur plusieurs exploitations, dont font partie les pareurs d'onglons professionnels intervenant sur les exploitations bovines suisses. Dans la présente étude, afin de donner un aperçu de la situation actuelle concernant la mise en oeuvre de mesures de biosécurité par les pareurs d'onglons, 49 pareurs d'onglons participant au programme suisse de santé des onglons, ont été questionnés à ce sujet et observés lors du parage des onglons par des vétérinaires. Le traitement des données a été effectué à l'aide d'un système de notation, attribuant des points aux différentes pratiques de travail selon leur potentiel supposé de transmission des maladies infectieuses que sont la Dermatite digitale (DD) et la Salmonellose. La pratique de travail, qui correspondait à la mesure de biosécurité idéale, obtenait toujours un point entier, alors que les pratiques de travail moins optimales ne recevaient qu'une valeur intermédiaire ou aucun point. Le système de notation a permis de désigner précisément les forces et les faiblesses des pareurs d'onglons en terme de biosécurité. Le niveau de mise en œuvre de mesures de biosécurité par les pareurs d'onglons est de manière générale relativement faible (53 % = moyenne du score de biosécurité générale des 49 pareurs). Les pareurs d'onglons ayant suivi plus fréquemment des formations spécifiques présentaient tendanciellement un niveau de mise en oeuvre de mesures de biosécurité plus élevé. De plus, les réponses des pareurs d'onglons et les observations des vétérinaires ont été comparées. Il a été constaté, que les pareurs d'onglons s'évaluaient généralement meilleurs en matière de biosécurité que les vétérinaires ne les jugeaient. En résumé et en tenant compte des résultats de cette étude, la propagation de germes pathogènes par les pareurs d'onglons dans le cadre de leur activité professionnelle, tels que les tréponèmes associés à la DD et les salmonelles, est possible. Par conséquent, la biosécurité devrait être thématisée en priorité lors des formations et formations continues futures.

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.

Broad-spectrum infrared thermography for detection of M2 digital dermatitis lesions on hind feet of standing dairy cattle.

Low-effort, reliable diagnostics of digital dermatitis (DD) are needed, especially for lesions warranting treatment, regardless of milking system or hygienic condition of the feet. The primary aim of this study was to test the association of infrared thermography (IRT) from unwashed hind feet with painful M2 lesions under farm conditions, with lesion detection as ultimate goal. Secondary objectives were to determine the association between IRT from washed feet and M2 lesions, and between IRT from unwashed and washed feet and the presence of any DD lesion. A total of 641 hind feet were given an M-score and IRT images of the plantar pastern were captured. Multivariable logistic regression analyses were done with DD status as dependent variable and maximum infrared temperature (IRTmax), lower leg cleanliness score and locomotion score as independent variables, and farm as fixed effect. To further our understanding of IRTmax within DD status, we divided IRTmax into two groups over the median value of IRTmax in the datasets of unwashed and washed feet, respectively, and repeated the multivariable logistic regression analyses. Higher IRTmax from unwashed hind feet were associated with M2 lesions or DD lesions, in comparison with feet without an M2 lesion or without DD, adjusted odds ratio 1.6 (95% CI 1.2-2.2) and 1.1 (95% CI 1.1-1.2), respectively. Washing of the feet resulted in similar associations. Dichotomization of IRTmax substantially enlarged the 95% CI for the association with feet with M2 lesions indicating that the association becomes less reliable. This makes it unlikely that IRTmax alone can be used for automated detection of feet with an M2 lesion. However, IRTmax can have a role in identifying feet at-risk for compromised foot health that need further examination, and could therefore function as a tool aiding in the automated monitoring of foot health on dairy herds.

Lesions found at foot trimming of dairy goats: Baseline data for comparing lesions and locomotion scoring.

Data on the foot lesions of housed dairy goats, especially those that are not lame, is sparse. In this study, visits were made to four farms for whole herd locomotion scoring after milking and to observe routine foot trimming. During trimming, the amount of trimming required for each hoof was recorded, alongside the presence of lesions. The process was repeated at the next routine foot trim on three of the four farms (on Farm 1 whole herd locomotion scoring after milking was not feasible). Across both visits, 3445 locomotion scores were recorded, alongside 3850 trimming and lesion records. There were large differences between farms and visits in the proportion of lame goats (6.7 to 25.5%) and in the proportion of goats which needed a substantial trim of all four feet (15.1-33.1%). Hoof lesions were observed in 65.5% of trimmed goats. We defined lesions by their site and presence of separation and/or granuloma, with white line separation being the most commonly recorded lesion (41.5% of goats). On all visits on the three farms which were locomotion scored, the number of goats recorded as lame was lower than the number observed with white line lesions, but the relative proportion ranged from 17% to 95.4%. Separations were much more common than granulomas, as granulomas were usually accompanied by separation. Toe lesions were much more likely to be associated with granulomas than white line lesions, with 91.5% of toe separations having granulomas but only 10.6% of white line separations. This study provides useful baseline data for comparing lesions and locomotion scoring between goat herds but also identifies areas where we need more data and more consensus.

Hoof lesions in partly housed pasture-based dairy cows.

Lameness is a symptom of a painful disorder affecting the limbs, which impacts dairy cow welfare and productivity. Lameness is primarily caused by hoof lesions. The prevalence of different lesion types can differ depending on environmental conditions and farm management practices. The aims of this observational study were to establish the cow-level and herd-level lesion prevalence during both housing and grazing periods in a partly housed, pasture-based system, establish the prevalence of lesions always associated with pain ("alarm" lesion), identify the lesions associated with a higher lameness score, determine relationships between lesions, and identify risk factors for digital dermatitis. On 98 farms during the grazing period and on 74 of the same farms during the housing period, every cow was lameness scored (0-3 lameness scoring scale), and the hind hooves of lame cows (score 2 and 3) were examined (maximum 20 cows per visit) and the prevalence of each lesion type recorded. To gather data on potential predictors for the risk factor analysis, a questionnaire with the farmer was conducted on lameness management practices and infrastructure measurements were taken at each visit. Cow-level data were also collected (e.g., parity, breed, milk yield, and so on). Noninfectious lesions were found to be more prevalent than infectious lesions in this system type. The most prevalent lesion types during both grazing and housing periods were white line separation, sole hemorrhages and overgrown claws; all remaining lesions had a cow-level prevalence of less than 15%. The cow-level prevalence of alarm lesions was 19% during the grazing period and 25% during the housing period; the most prevalent alarm lesion was sole ulcers during both periods. We found significantly more foreign bodies within the hoof sole (grazing = 14%, housing = 7%) and overgrown claws (grazing = 71%, housing = 55%) during the grazing period compared with the housing period. Cows with foul of the foot, sole ulcer, white line abscess, toe necrosis or an amputated claw had higher odds of being more severely lame, compared with mildly lame. The strongest correlation between lesions were between toe necrosis and digital dermatitis (r = 0.40), overgrown claws and corkscrew claws (r = 0.33), and interdigital hyperplasia and digital dermatitis (r = 0.31) at herd level. At the cow level, the strongest correlation was between overgrown claws and corkscrew claws (r = 0.27), and digital dermatitis and heel erosion (r = 0.22). The farmers' perception of the presence of digital dermatitis (and lameness) was significantly correlated with the actual presence of digital dermatitis recorded. Additional risk factors for the presence of digital dermatitis were cow track and verge width near the collecting yard, and stone presence on the cow tracks. Results from this study help further our understanding of the causes of lameness in partly housed, pasture-based dairy cows, and can be used to guide prevention and treatment protocols.

A case-control study regarding factors associated with digital dermatitis in Norwegian dairy herds.

BACKGROUND: Digital dermatitis (DD) is a contagious bovine foot disease causing painful lesions, lameness, and reduced animal welfare. Previous studies indicate a complex aetiology of the disease. The aim of this study was to compare DD negative and DD positive herds to identify factors associated with DD in Norwegian dairy herds by analysing data obtained in a questionnaire and data recorded in the Norwegian Dairy Herd Recording System (NDHRS). The questionnaire was e-mailed to the owners of all 380 herds recorded with DD in 2019 and to 1530 randomly selected herds with no recordings of DD. Altogether 559 dairy herds were included in the final study population, of which 113 was classified as DD positive (≥ one cow recorded with DD in NDHRS) and 446 as DD negative. When stratified by housing system, the ratio between DD positive and negative herds was 108/281 in free stalls and 5/165 in tie stalls. Multilevel logistic regression was used to model the association between potential risk factors and variables related to the detection and diagnosis of DD, and the outcome in the free-stall population. Geographical area (county) was included in the model as a random effect. RESULTS: In the final study population 108/113 (96%) of the DD positive herds were housed in free stalls versus 5/113 (4%) in tie stalls. The free-stall herds' DD status was associated with purchase of cattle during the last 5 years (baseline: 0 animals, OR = 2.30 for category 12-27 animals, OR = 4.34 for 28-52 animals, and OR = 5.39 for ≥ 53 animals). The DD status was also associated with claw trimming frequency (Baseline: 1 < 2/year, OR = 0.41 for category < 1/year, and OR = 4.09 for ≥ 3/year), whether the claw trimming was done by a certified professional trimmer or not (baseline: ≤ 90% of the cows, OR = 3.98 for category ≥ 90% of the cows), cleaning of feet in the chute before trimming (baseline: no cleaning, OR = 1.98 for category cleaning), and alley flooring (baseline: slatted floor, OR = 2.36 for category solid floor). CONCLUSIONS: Digital dermatitis was far more frequent in Norwegian dairy herds housed in free stalls versus those housed in tie stalls. In the free-stall herds purchase of cattle, increasing trimming frequency, use of certified professional trimmer, cleaning of the feet in the chute, and solid flooring in the alleys were associated with increased odds of recorded DD.

Multi-modality imaging of aggressive submural neoplasia of the hoof in two horses.

This case series presents a 20-year-old Quarter horse gelding and a 10-year-old Thoroughbred gelding with a histologic diagnosis of aggressive submural neoplasia, including an anaplastic sarcoma and a squamous cell carcinoma respectively. The current case series describes these neoplasias with radiography, computed tomography, magnetic resonance imaging and histopathology with immunohistochemistry. The purpose of this case series is to identify the clinical pattern of chronic reoccurring lameness in these cases and highlight the appearance of expansile osteolytic pathology of the distal phalanx with adjacent hoof wall abnormalities. Advanced imaging has the potential to assist with a differential diagnosis list and surgical planning in patients such as these however obtaining a cellular sample for histopathological examination remains necessary for definitive diagnosis.

Using a target trial approach to evaluate the role of hyperketonemia in sole ulcer and white line hoof lesion development.

This observational cohort study enrolled cows from 7 freestall dairy herds in Minnesota and Wisconsin. The objective was to estimate the causal role of hyperketonemia on new sole ulcer and white line hoof lesions (SUWL). Multiparous cows were enrolled at the time of their precalving hoof trim, at the end of their previous lactation. Enrolled cows were hoof trimmed twice: precalving between 90 to 21 d before calving (n = 2,037), and postcalving between 21 to 150 d after calving (n = 1,408). We trained 7 commercial hoof trimmers, employed by the farms, in lesion identification to standardize lesion recording. Hoof trimmers conducted therapeutic trimming as well as diagnosing and treating lesions. After parturition, cows between 3 and 16 d in milk were tested once weekly for hyperketonemia using a hand-held ketone meter. Farm staff and research personnel conducted the ß-hydroxybutyrate (BHB) testing. Cows were classified as hyperketonemic (HYK+) if they had a blood BHB ≥1.2 mmol/L or hyperketonemia-negative (HYK-) if blood BHB <1.2 mmol/L. At the precalving hoof trim, 15.6% of cows trimmed had a lesion and 1.9% of cows had a SUWL; thus, cows with a SUWL were excluded from further analysis (n = 38). At the postcalving hoof trim, 25.8% of cows trimmed had a hoof lesion, and 3.6% of cows had a SUWL. The most prevalent lesions at the pre- and postcalving hoof trims were digital dermatitis and corkscrew lesions. The incidence of hyperketonemia among cows was 21.1% (421/1,999) and the incidence on farms ranged from 5.7 to 29.1%. After excluding cows due to being hoof trimmed outside our designated window, the multilevel logistic regression model for the odds of SUWL at the postcalving hoof trim included 1,209 cows (HYK+ = 257/1,209; SUWL = 42/1,209). The odds of having SUWL in HYK+ was 0.66 (95% confidence interval: 0.29, 1.49) times the odds of that for HYK- cows. For cows diagnosed with a lesion (digital dermatitis, corkscrew, toe, foot rot, or other lesion) at their precalving hoof trim (n = 199), the odds of having SUWL for HYK+ cows were 0.43 (95% confidence interval: 0.05, 3.92) times the odds of that for HYK- cows. The wide range of compatible causal estimates suggest that hyperketonemia likely has a limited role in the development of SUWL in cows with or without a hoof lesion precalving. Future research should investigate other transition period factors such as inflammation or structural changes to the foot that may have a causative role in the development of SUWL.