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.

A scoring system for grading corkscrew claws in dairy cattle.

Corkscrew claw (CC) in dairy cattle is increasingly reported in dairy herds. CC is a progressive deformity of the claw capsule with uncertain aetiology and pathogenesis. Genetics and specific environmental factors are suspected of contributing to the development of this irreversible condition. CC has been found in lame cows; however, the cause and effect has not been established. To perform analysis of risk factors, treatment and pathogenesis, a definition of severity scores is called for. The aim of this study was to measure and analyse CC characteristics from photos of cows' feet to describe and evaluate a scoring system for CC. Width of the visible part of the axial wall, degree of contact between the toe and the floor and angle of the distal part of the abaxial wall as a proxy for the deviation of the abaxial wall was measured from 393 pictures of CC. Based on the measurements on the claws, the parameter "width of the axial wall" was chosen to define the scores. The parameter was divided into three intervals to define either mild CC 0.3-2.0 cm, moderate CC 2.1-3.5 cm or severe CC>3.5 cm and correlation between the parameters; level of contact between the toe and the floor and the angle of the distal abaxial wall was evaluated. There was a significant positive linear correlation between width of the axial wall and angle of the distal part of the abaxial wall (r=0.91), the wider the axial wall, the more the abaxial wall deviated in the distal part. As the width of the axial wall increased the toe increasingly lost contact with the floor, this association was significant for mild CC and moderate CC but not for severe CC. The Interobserver agreement of the CC Scoring system was tested by 30 claw trimmers each scoring 32 cadaver feet and by 2 trained observers on 28 photos of feet using Cohen´s weighted kappa and showed substantial to almost perfect agreement between untrained and trained observers, respectively.

Neutrophil extracellular traps and active myeloperoxidase concentrate in lamellar tissue of equids with naturally occurring laminitis.

Laminitis is a pathology of the equine digit ultimately leading to a failure of the dermo-epidermal interface. Neutrophil activation is recognized as a major factor in SIRS-associated laminitis and has recently been described in induced endocrinopathic laminitis evidenced by the presence of myeloperoxidase (MPO). Neutrophil extracellular traps (NET) are released with neutrophil activation. This study aimed to investigate the presence and activity of MPO and NET in the lamellar tissue of equids presented with naturally occurring laminitis. Samples of lamellar tissue of five horses and five donkeys presented with laminitis, as well as eight control horses without laminitis, were collected. Lamellar tissue extracts were submitted to ELISA and specific immuno-extraction followed by enzymatic detection (SIEFED) assays to confirm the presence and activity of both MPO and NET. Lamellar sections were also immunohistopathologically stained for MPO and NET. Analysis of lamellar tissue extracts revealed that laminitis cases had significantly higher levels of total MPO concentration, MPO activity, and NET-bound MPO activity in comparison to control horses. Moreover, a strong correlation was identified between the activity of NET-bound MPO and the total MPO activity, which suggests that MPO activity partly originates from NET-bound MPO. Immunohistochemical staining showed that MPO and NET labelling in laminitis cases was moderate to marked, primarily in the epidermis and in inflammatory infiltrates containing neutrophils, while labelling in control horses was minimal. This article constitutes the first indication of the presence and activity of NET-bound MPO in the lamellar tissue of horses and donkeys with naturally occurring laminitis. Targeting these substances may provide new treatment possibilities for this debilitating disease.

Effects of Salvinia as a broiler litter material on growth performance, behavior, welfare parameters, litter characters, and ammonia emission.

The type of litter material has direct impacts on production, behavioral, and welfare parameters of broilers. The price of conventionally-used litter materials is increasing. Salvinia molesta is a fast-growing aquatic plant which has become an environmental issue in some areas. This study assessed the suitability of air-dried Salvinia plants (SAL) as an alternate litter material to paddy husk (PH). Resulting in a completely randomized experiment, a total of 240 broilers was raised in 12 floor-pens each provided with either PH or SAL as litter materials, from 11 to 36 d. Scan sampling technique was employed to record the birds' engagement in 15 predetermined behaviors. Foot pad dermatitis (FPD), hock burn damage (HBD) and plumage cleanliness (PC) were assessed using Welfare Quality Scoring System. Litter samples were analyzed for pH, dry matter%, water holding capacity, porosity, N%, tapped-density and ammonia emission rate. The litter material had no significant effect (P > 0.05) on mortality, growth performance parameters, dressing % and visceral organ weight. The scores for FPD and PC were unaffected by the litter materials. SAL litter reported significantly lower (P < 0.05) HBD scores. The percentages of birds engaged in eating and wing flapping behaviors were significantly lower on SAL. Litter type had no significant influence on the color, aroma, flavor, texture and overall acceptability of breast meat. Air-dried Salvinia plants reported acidic pH. SAL litter gave a significantly higher tapped-density. Ammonia emission rate of SAL litter was significantly lower than that of PH. However, the final litter N content was higher for PH (3.7%) than SAL (3.2%). The study proposes air-dried Salvinia plants as a litter material for broilers since it gives growth performance comparable to PH with reduced hock burn damage incidences. Effects of SAL on behavior and the fertilizer value of the spent litter are to be studied further.

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.

An abattoir study of the prevalence of foot lesions and claw measurements in water buffalo in Egypt.

BACKGROUND: Lameness has been associated with compromised animal welfare and reduced productivity in dairy cattle herds worldwide. However, little is known about the prevalence of claw lesions in the dairy buffalo population in Egypt. Furthermore, the optimum measurements for claw trimming in buffalo are unknown. A cross-sectional cadaver study was conducted where 135 pair buffalo hind feet were collected from 4 slaughterhouses and examined for the presence of claw lesions. The proportion and associated 95% confidence interval (CI) of each type of lesion were calculated. A separate set of healthy claws (n = 26) underwent ultrasonography (US) and computed tomography (CT). The agreement between US and CT measurements was assessed using Passing-Bablok regression and intraclass correlation coefficient. The CT measurements were used to calculate trimming recommendations. RESULTS: At least one lesion was identified in 242 claws (89.6%, 95% CI = 85.4-93.0). In healthy claws, poor to moderate agreement was identified between US and CT measurements which could be due a sample size of the study. The average ± standard deviation (SD) minimum recommended external wall length of the lateral and medial claws in heifers was 7.1 ± 0.36 cm and 7.5 ± 0.35 cm, respectively. The average ± SD minimum recommended external wall length in buffaloes over five years of age was 8.2 ± 0.27 cm and 8.4 ± 0.39 cm for the lateral and medial claws, respectively. CONCLUSIONS: The study found a high prevalence of claw lesions in buffalo in Egypt, the clinical significance of which requires further elucidation. Recommended measurements will help guide claw trimming in buffalo to minimise lesions.

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

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

Radiographic analysis of the dorsal hoof wall thickness in clinically normal draft horses.

OBJECTIVE: To evaluate the radiographic thickness of the dorsal hoof wall in normal draft horse feet. ANIMALS: 33 adult draft horses with no history of laminitis, no clinically obvious lameness, and visibly unremarkable front feet were included. METHODS: This was a prospective, descriptive study of clinically normal draft horses' front feet. Lateromedial radiographs were acquired of the front feet. A ratio of the dorsal hoof wall thickness to the length of the distal phalanx (DHWP3 ratio) was calculated. RESULTS: The dorsal hoof wall thickness to length of the distal phalanx was calculated as 0.33 ± 0.03 (range of 0.28 to 0.39) in this population of draft horses. CLINICAL RELEVANCE: With very few exceptions, the heterogeneous population of draft horses evaluated in this study had a DHWP3 ratio greater than previously published values in lighter breeds (< 0.30).

Prolonged hyperinsulinemia increases the production of inflammatory cytokines in equine digital lamellae but not in striated muscle.

Hyperinsulinemia is the key feature of equine metabolic syndrome (EMS) which leads to debilitating sequelae. Hyperinsulinemia-associated laminitis (HAL) is one of the major sequelae of EMS, although the pathophysiological mechanisms are not well elucidated. Using an equine model, we hypothesized that expression of inflammatory markers would be increased in digital lamellae and striated muscle following prolonged hyperinsulinemia. Healthy Standardbred horses (5.4 ± 1.9 years) were alternately assigned to a prolonged euglycemic-hyperinsulinemic clamp (pEHC) or control group (n = 4 per group). Following a 48 h pEHC or a 48 h infusion of a balanced electrolyte solution (controls), biopsies were collected from digital lamellar tissue, skeletal muscle and cardiac muscle were obtained. All hyperinsulinemic horses developed laminitis regardless of previous health status at enrollment. Protein expression was quantified via Western blotting. A significant (P < 0.05) upregulation of the protein expression of heat shock protein 90 (HSP90), alpha 2 macroglobulin (A2M) and fibrinogen (α, ß isoforms), as well as inflammatory cytokines including interleukin-1ß were detected in digital lamellae following prolonged hyperinsulinemia. In contrast, protein expression of cytokines and acute phase proteins in heart and skeletal muscle was unchanged following hyperinsulinemia. Upregulation of inflammatory cytokines and acute phase proteins in digital lamellae during prolonged hyperinsulinemia may reveal potential biomarkers and novel therapeutic targets for equine endocrinopathic laminitis. Further, the lack of increase of inflammatory proteins and acute phase proteins in striated muscle following prolonged hyperinsulinemia may highlight potential anti-inflammatory and cardioprotective mechanisms in these insulin-sensitive tissues.

Short-term induced hyperinsulinaemia and dexamethasone challenge do not affect circulating total adiponectin concentrations in insulin-sensitive ponies.

BACKGROUND: Hypoadiponectinaemia is a risk factor for endocrinopathic laminitis, but the directionality and nature of its association with insulin dysregulation is unclear. OBJECTIVES: To investigate the effects of short-term induced hyperinsulinaemia and dexamethasone challenge on circulating [total adiponectin] and whole blood expression of adiponectin (AdipoR1 and AdipoR2), insulin, and insulin-like growth factor 1 (IGF-1) receptors in insulin-sensitive ponies. STUDY DESIGN: In vivo experiment. METHODS: Six never-laminitic, insulin-sensitive, native-breed UK ponies first underwent a dexamethasone challenge (0.08 mg/kg i.v.) with blood samples collected every 15 min over 3 h. After a 14-day washout period, hyperinsulinaemia was induced for 9 h via a euglycaemic-hyperinsulinaemic clamp (EHC), with blood samples collected every 30 min. Serum [insulin], plasma [total adiponectin], and plasma [IGF-1] were measured using validated assays and receptor gene expression was assessed via quantitative polymerase chain reaction (qPCR). Finally, whole blood was incubated with 10-1000 ng/mL dexamethasone for 3 h at 37°C to investigate its direct effects on gene expression. RESULTS: There were no adverse effects observed during either protocol. Dexamethasone challenge did not alter circulating [insulin] or [total adiponectin] at any time-point, but significantly upregulated AdipoR1 and IGF-1R expression at 150 and 180 min. Ex vivo incubation of whole blood with dexamethasone did not alter expression of the genes examined. There was no change in [total adiponectin] or expression of the genes examined associated with EHC-induced hyperinsulinemia. MAIN LIMITATIONS: This was a small sample size that included only native-breed ponies; total adiponectin was measured rather than high-molecular-weight adiponectin. CONCLUSIONS: Short-term induced hyperinsulinaemia and dexamethasone challenge did not affect circulating [total adiponectin] in insulin-sensitive ponies. However, dexamethasone administration was associated with upregulation of two receptors linked to adiponectin signalling, suggesting that a physiological response occurred possibly to counteract dexamethasone-associated changes in tissue insulin sensitivity.

Ex vivo study shows novel, rapid, suture-free tenotomy technique for the equine deep digital flexor tendon.

OBJECTIVE: To describe the feasibility of a novel thread-transecting technique for the tenotomy of the equine deep digital flexor tendon (DDFT). ANIMALS: 39 equine distal limb specimens. METHODS: Under ultrasonographic guidance, a surgical thread was percutaneously placed around the DDFT through 2 needle punctures (lateral and medial) using a Tuohy needle in equine limbs (22 forelimbs, 17 hindlimbs). The DDFT was transected by a back-and-forth motion of the thread until the loop emerged from the entry puncture site. Each specimen was dissected and assessed for completeness of transection and iatrogenic damage under direct visualization. Descriptive statistics were reported. RESULTS: Complete DDFT transection was achieved in all 39 limbs, taking an average of 8.6 minutes per procedure. Iatrogenic damage to surrounding structures occurred in 17 (44%) limbs, with 6 (15%) limbs having more than 1 structure damaged. Damage to the communicating branch of the palmar or plantar nerves was the most commonly seen. CLINICAL RELEVANCE: DDFT tenotomy in equine limb specimens was effectively performed using a novel thread-transecting technique. The procedure is quick, and no suturing is needed, but damage to surrounding structures is possible. Further assessment of the procedure and clinical significance of its potential iatrogenic damage in clinical cases is needed.

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.

Evaluation of field-testing protocols to diagnose insulin dysregulation in ponies using a Bayesian approach.

Field tests and their association with laminitis have not been evaluated in large cohorts. The objectives of this study were to evaluate the performance of basal insulin (BI), the oral sugar test (OST) and the insulin tolerance test (ITT) to diagnose ID and investigate their association with laminitis. Insulin dysregulation status was determined in 146 ponies using BI (insulin concentration >20 µIU/mL), an OST (insulin concentration >65 µIU/mL at 60 or 90 min after oral administration of 0.45 mL/kg corn syrup) and an ITT (< 50% reduction in glucose concentration 30 min after intravenous administration of 0.1 IU/kg insulin). Laminitis was identified using modified-Obel scores. A Bayesian approach was used to define the characteristics of the tests and receiver operating characteristic curves were used to assess their association with laminitis. All tests were well tolerated and laminitis was diagnosed in 9% of ponies. Insulin dysregulation was diagnosed in 15% of ponies using BI, 38% using the OST and 54% using the ITT with 11% of ponies positive for all three tests. The sensitivities and specificities of BI, the OST and the ITT to diagnose ID were 0.52 (95% confidence interval [CI], 0.35-0.79) and 0.97 (95% CI, 0.91 - 1.00), 0.84 (95% CI, 0.70 - 0.94) and 0.60 (95% CI, 0.49 - 0.71), and 0.85 (95% CI, 0.68-0.96) and 0.88 (95% CI, 0.75 - 0.97), respectively. Only BI and the OST were associated with laminitis (P = 0.003 and 0.015, respectively).

Continuous digital hypothermia for prevention and treatment of equine acute laminitis: A practical review.

Laminitis is a severely debilitating and life-threatening condition that occurs as a consequence of different primary triggering factors. Continuous digital hypothermia (CDH) is recommended in horses at risk of, or diagnosed with, acute laminitis due to its several physiological and biochemical alterations that may be positive for the prevention and early treatment of the condition, representing a low risk of adverse effects. Modulation of the inflammatory response, profound vasoconstriction, and prevention of tissue damage are the most notable protective effects of cryotherapy on the lamellae. This practical review aims to summarize the published literature evaluating CDH efficacy in the prevention and early treatment of acute laminitis in horses, highlighting the most important clinical findings and discussing the best methods to provide cryotherapy. Nineteen publications evaluated different CDH methods, including the use of commercially available ice boots or fluid bags filled with iced water or crushed ice, as well as alternatives to immersion in ice, e.g., frozen gel packs and a perfused cuff prototype. Although some techniques were effective for cooling and maintaining the hooves below the optimal temperature of 10 °C, relevant limitations such as labor intensiveness, reliance on an ice source and price make its use impractical in some clinical situations. Twelve experimental studies assessed the efficacy of CDH on the prevention or early treatment of laminitis, finding multiple positive effects in terms of clinical improvement, immunological and inflammatory modulation, and histological protection. After the analysis of the literature, the clinical importance of CDH in different stages of laminitis remains clear. However, it also highlights the need for a safer, more user-friendly, and more effective method of cryotherapy that can be used both in a hospital and an ambulatory setting.

Investigating the effect of prophylactic claw trimming on the interval between calving and first observed elevated locomotion score in pasture-based dairy cows.

AIMS: To evaluate, in a pasture-based dairy herd, the response to a three-time point hoof trimming regime on lameness incidence and time from calving to observation of an elevated locomotion score (LS). METHODS: This study was conducted on a 940-cow spring-calving herd in New Zealand's North Island between May 2018 and May 2019. Cows (n = 250) were randomly allocated to the hoof trimming group, with the remainder assigned to the non-trim cohort. One trained professional hoof trimmer used the five-step Dutch method to trim the hind feet of the trimming group. Throughout the subsequent production season, the whole herd was locomotion-scored fortnightly using the 4-point (0-3) Dairy NZ lameness score. Kaplan-Meier survival curves were used to assess the univariable effect of trimming on the interval between calving and first LS of ≥ 2 and first LS ≥ 1. A multivariable Cox proportional hazards regression was used to further evaluate the effect of trimming on time to elevated LS. RESULTS: Mean lameness (LS ≥ 2) prevalence was 2.6%, with 30% of cows having ≥ 4 observations during the study period when at least one LS was ≥ 2. For LS ≥ 1, mean prevalence was 40%, with 98.6% of cows having ≥ 4 observations during the study period when at least one LS was ≥ 1 during lactation. Hoof trimming had no apparent effect on the incidence of clinical lameness (LS ≥ 2) (trimmed vs. non-trimmed: 33.2% vs. 28.8%, respectively), but for LS ≥ 1, there was a small decrease in the incidence of LS ≥ 1 (trimmed vs. non-trimmed: 96.9% vs. 99.3%, respectively). The hazard of a cow having a first observed LS ≥ 2 in the control group was 0.87 (95% CI = 0.66-1.14) times that of the trimmed group; however, the hazard of a cow having a first LS ≥ 1 was 1.60 (95% CI = 1.37-1.88) times higher in the control than in the trimmed group. CONCLUSION AND CLINICAL RELEVANCE: On this farm, prophylactic hoof trimming had no clinically relevant impact on the incidence of clinical lameness and was not associated with clinically beneficial reductions in time to first observed LS ≥ 2. This may be because claw horn imbalance was not pronounced on this farm, with 53% of cows needing no trim on either hind limb on the first trimming occasion. Further research on the response to prophylactic trimming in pasture-based dairy cattle is required.

Prevalence and risk factors for laminitis within the Norwegian pony breed Nordlandshest/Lyngshest.

BACKGROUND: Laminitis is a systemic condition resulting in debilitating pain and structural changes within the feet, and hence has major welfare implications. Causes include endocrine and systemic inflammatory conditions. Ponies are frequently affected, and observations in the field suggest that occurrence of laminitis is also common in Norwegian breeds. The aim of this study was to estimate the prevalence and risk factors for laminitis within the Norwegian pony breed Nordlandshest/Lyngshest. RESULTS: The study was a cross-sectional study based on questionnaires sent to members of the Norwegian Nordlandshest/Lyngshest breed association. Questionnaires were received for 504 animals, of which 464 records were eligible and included in analyses. The population comprised 71 stallions, 156 geldings, and 237 mares, with an age between 1 and 40 years (median and interquartile ranges: 12 (6-18) years). The estimated 3-year period prevalence of laminitis was 8.4% (95% confidence interval (CI95): 6.0-11.3%), whereas lifetime prevalence was 12.5% (CI95: 9.6-15.9%). Mares had a significantly higher period- and lifetime prevalence of laminitis than male horses, and horses 10 years and older had a significantly higher prevalence than younger horses. The lifetime prevalence of laminitis was 3.2% in horses 9 years and younger, whereas from 17.3-20.5% in older horses. Multivariable logistic regression analysis identified age, sex, and regional adiposity as significantly (P < 0.05) associated with the 3-year period outcome of laminitis: Horses older than 9 years had a three-fold increase in the likelihood of having laminitis compared to the younger horses (Odds Ratio (OR)10-14 years = 3.37 (CI95 = 1.19-9.50), OR15-19 years = 3.06 (CI95 = 1.04-9.05), and OR>20 years = 2.70 (CI95 = 0.90-8.02). Mares were more than twice as likely (OR = 2.44 (CI95 = 1.17-5.12) to have laminitis compared to male horses, and horses with regional adiposity had increased odds (OR = 2.35 (CI95 = 1.15-4.82) of laminitis compared to horses without regional adiposity. CONCLUSIONS: Laminitis appears to be a considerable welfare issue in the Norwegian pony breed Nordlandshest/Lyngshest. The identified risk factors age, sex, and regional adiposity highlight the need for improved owner education and awareness of strategies to reduce laminitis risk.

Histological comparison of the lamellar tissue of Iberian origin breed horses created in semi-feral conditions or in an intensive system.

Although the external conformation of wild horse hooves has been proposed as an ideal model for domesticated modern horses, histological signs of laminitis have been reported among them. With the hypothesis that the lamellar tissue of horses of Iberian origin raised in semi-feral is healthier than those raised in an intensive management system (stall confinement and high-calorie diet intake), the objective was to compare their lamellar tissues. Lamellar tissue samples were taken from the forelimb hoof of eight domesticated Mangalarga Marchador (MM) horses and from six semi-feral Marajoara (MJ) and Puruca (MP) horses. Primary epidermal lamella (PEL) and secondary epidermal lamella (SEL) were measured (length and width) in several regions, and their shapes were morphologically classified into different types. Breed groups were compared using analysis of variance, followed by Tukey or Dunn tests (P<0.05). Early signs of laminitis such as abnormal keratinization of the abaxial primary dermal lamella, tapered tips of the axial PELs, pointed tips of the SEL, nuclei condensation, and abnormal spatial orientation of the secondary epidermal basal cells (SELBC), were seen only in MM horses. MP horses had a greater interface of epidermis/dermis contact than MJ horses and more rounded nuclei in the round SELBC than MM horses. In agreement with the study hypothesis, semi-feral MJ and MP horses' lamellae were classified as healthier than MM horses, which showed early signs of endocrinopathic laminitis.

[Risk factors for infectious foot -disorders on two Swiss cattle -mountain pastures]. / Risikofaktoren für infektiöse Zehen­erkrankungen auf zwei Schweizer ­Rinderalpen.

INTRODUCTION: In the present study, risk groups for infectious foot disorders were identified on two large Swiss cattle mountain pastures by analyzing animal and treatment data of a total of 3256 animals of the bovine species. Both mountain pastures were part of the Federal Office for Agriculture (FOAG) consultancy project «Healthy animals, attractive herdsmen positions and less medication on large cattle mountain pastures¼. The project was launched in 2020 following the increased incidence of lameness on these mountain pastures. Bacteriological and histological analyses were to provide information as to whether the most common foot disorder was interdigital phlegmon (IP) or whether digital dermatitis also occurred. Further, the temporal distribution of cases over the mountain pasture season and the influence of mountain pasture and year were investigated and interpreted for the project years 2020 to 2022, and treatment incidences were compared between years. Multiple treatment cycles in the same individual were classified into persistent infections and new infections. Nineteen of 394 first-treated cattle were clinically examined, 12 of them were additionally sampled for bacteriological and histological analyses. All cases examined showed, both clinically and following laboratory analyses, typical characteristics for IP. In contrast, there was no specific evidence for the presence of digital dermatitis. No persistent infections occurred during treatment with benzylpenicillin. Multivariate logistic regression analyses identified > 365-730-day-old cattle (odds ratio OR 8,29), as well as inseminated (OR 5,30) and non-inseminated (OR 7,85) heifers as risk groups for the disease studied (p < 0,05). Association with the oestrus activity of non-inseminated heifers and a generally higher locomotor activity in heifers compared to cows - with a correspondingly increased risk of injury - is conceivable. Meat breeds had a reduced risk compared to dairy breeds (OR 0,29). Breed differences in behavior and/or the effectiveness of the local immune response might have an impact. Knowing about these risk groups can be put to use in the future when selecting animals to be taken to the mountain pastures and/or when planning pasture management in order to reduce the prevalence of infectious foot disorders and thereby the use of antibiotics.

INTRODUCTION: Dans la présente étude, nous avons identifié, grâce à l'analyse des données concernant les animaux et les traitements d'un total de 3256 animaux de l'espèce bovine, des groupes à risque pour les maladies infectieuses des onglons sur deux grands alpages bovins en Suisse. Les deux alpages faisaient partie du BLW-projet de conseil «Animaux sains, postes de bergers attractifs et moins de médicaments sur les grands alpages bovins¼. Le projet a débuté en 2020 suite à l'accumulation de problèmes de boiteries sur ces alpages. Des analyses bactériologiques et histologiques devaient fournir des indications afin de savoir si la maladie des onglons majoritaire était le phlegmon interdigité (PI) ou si la dermatite digitale était également présente. La répartition temporelle des cas de maladies durant la saison d'estivage et l'influence de l'alpage et de l'année pour les années de projet 2020 à 2022 ont été évaluées et interprétées, et les incidences des traitements comparées entre les années. Les cycles de traitement multiples chez le même individu ont été répartis en deux groupes: les infections persistantes et les nouvelles infections. Dix-neuf des 394 bovins primo-traités ont été évalués cliniquement. Douze de ces 19 animaux ont également été soumis à un échantillonnage bactériologique et histologique. Tous les cas étudiés présentaient, aussi bien cliniquement que suite à l'analyse technique en laboratoire, les caractéristiques typiques d'un PI. Par contre, il n'y a pas eu d'indication quant à la présence de dermatite digitale. Aucune infection persistante n'a été constatée après traitement avec de la Benzylpénicilline. Les bovins âgés > 365­730 jours (OR 8.29), ainsi que les génisses inséminées (odds ratio OR 5.30) et non inséminées (OR 7.85) ont été identifiés, suite à une analyse de régression logistique multivariée, comme faisant partie de groupes à risque pour la maladie étudiée (p < 0.05). Un lien avec l'activité en période de chaleurs des génisses non inséminées et une activité locomotrice généralement plus intensive des génisses par rapport aux vaches ­ avec par conséquent un risque accru de blessures ­ est concevable. Le risque était réduit pour les races à viande par rapport aux races laitières (OR 0.29). Des différences de comportement et/ou d'efficacité de l'immunité locale entre les races pourraient avoir une influence. Le fait de connaître ces groupes à risque pourrait être mis à profit à l'avenir lors de la sélection des animaux à monter à l'alpage et/ou lors de la planification de la gestion des prairies, afin de diminuer la prévalence des maladies infectieuses des onglons et ainsi l'utilisation d'antibiotiques.