Background: Although thoracic auscultation (AUSC) in calves is quick and easy to perform, the definition of lung sounds is highly variable and leads to poor to moderate accuracy in diagnosing bronchopneumonia (BP). Hypothesis/Objectives: Evaluate the diagnostic accuracy of an AUSC scoring system based on a standard lung sound nomenclature at different cut-off values, accounting for the absence of a gold standard test for BP diagnosis. Animals: Three hundred thirty-one calves. Methods: We considered the following pathological lung sounds: increased breath sounds (score 1), wheezes and crackles (score 2), increased bronchial sounds (score 3), and pleural friction rubs (score 4). Thoracic auscultation was categorized as AUSC1 (positive calves for scores ≥1), AUSC2 (positive calves for scores ≥2), and AUSC3 (positive calves for scores ≥3). The accuracy of AUSC categorizations was determined using 3 imperfect diagnostic tests with a Bayesian latent class model and sensitivity analysis (informative vs weakly informative vs noninformative priors and with vs without covariance between ultrasound and clinical scoring). Results: Based on the priors used, the sensitivity (95% Bayesian confidence interval [BCI]) of AUSC1 ranged from 0.89 (0.80-0.97) to 0.95 (0.86-0.99), with a specificity (95% BCI) of 0.54 (0.45-0.71) to 0.60 (0.47-0.94). Removing increased breath sounds from the categorizations resulted in increased specificity (ranging between 0.97 [0.93-0.99] and 0.98 [0.94-0.99] for AUSC3) at the cost of decreased sensitivity (0.66 [0.54-0.78] to 0.81 [0.65-0.97]). Conclusions and Clinical Importance: A standardized definition of lung sounds improved AUSC accuracy for BP diagnosis in calves.

Background: Lung auscultation is a common method for the routine diagnosis of calf bronchopneumonia. However, its repeatability among operators has been criticized. Objective: Determine agreement among veterinarians for specific lung sounds after a short tutorial to standardize the definition of lung sounds. Animals: Forty lung sounds from a larger dataset collected at 4 veal calf farms that housed 495–815 animals were submitted online to 10 different veterinarians. Methods: After a short tutorial on lung sound auscultation, the raters were asked to detect the presence of any abnormal sounds and to differentiate among wheezes, crackles, and bronchial sounds. Raw percentage of agreement (PA), Gwet's agreement coefficient type 1 (AC1), Krippendorff's alpha (Ka), and Fleiss kappa (KFleiss) were chosen as agreement indicators in the absence of a gold standard indicator to assess agreement. The different indicators were interpreted based on a priori reported benchmarks. Results: The agreements were fair to good for almost all lung sound indicators. For the presence of any abnormal lung sound, the reported agreements (95% confidence intervals [CI]) were 0.781 (0.716–0.845), 0.646 (0.514–0.777), 0.403 (0.351–0.455), and 0.293 (0.137–0.493) for PA, AC1, Ka, and KFleiss, respectively. The same indicators were 0.769 (0.694–0.845), 0.615 (0.446–0.784), 0.426 (0.378–0.475), and 0.425 (0.293–0.563) for wheezes, 0.754 (0.685–0.823), 0.643 (0.503–0.782), 0.21 (0.146–0.275), and 0.208 (0.097–0.327) for crackles, and 0.636 (0.571–0.701), 0.345 (0.179–0.512), 0.182 (0.131–0.232), and 0.18 (0.081–0.279) for bronchial sound detections, respectively. Conclusion and Clinical Importance: Agreement among raters auscultating calf respiratory sounds was higher than previously reported. However, improvement is still possible to increase auscultation agreement.

Each year ∼150,000 surplus calves are sold at auction markets in Québec, Canada. Surplus calves (male or female not kept in the herd of origin) are sold at a young age, but these animals are at risk of receiving lower quality neonatal care than replacement heifers. Knowledge of factors associated with a higher selling price could help convince farmers to spend more resources in the care surplus calves. Our objective was to explore the associations between farm management practices and the median percentile of surplus calf selling price per farm at auction markets. The price (Canadian dollars/kg of BW) and the individual identification number of surplus calves sold in 2 auction markets in Québec during 4 sale days in the summer 2019 and in the winter 2020 were recorded. The recorded price of each surplus calf was transformed as percentile for each breed and day of sale. Farmers managing the surplus calves were contacted and interviewed on farm management practices. The data from farmer's interviews were analyzed as potential variables associated with the median percentile of calves' selling price per farm (farm-level dependent variable) in a multivariable linear regression model. A total of 509 farmers were contacted, of which 433 farmers agreed to participate, and 409 interviews were retained for statistical analysis. The farms enrolled in the study had sold a median of 2 calves (range 1-19 calves) during the sale days considered. The main breed of surplus calves sold were Holstein (82%) and Angus crossbred calves (9%). The results from the multivariable model showed that median percentile of calves' selling price was positively associated with farms with an average milk production per cow superior to 11,000 L/yr (β 0.13, 95% CI: 0.045, 0.221) and farms with 3 or more workers available to take care of surplus calves (β 0.08, 95% CI: 0.005, 0.167). Those results indicate that farms having an average milk production per cow superior to 11,000 L/yr increase the calves' selling price by 13 percentiles (i.e., from 50th to 63rd) and that farms having at least 3 caretakers increase their median percentile calves' selling price by 8 percentiles (i.e., from 50th to 58th). Median percentile of calves' selling price was negatively associated with farms that vaccinated cows for neonatal calf diarrhea (β -0.06, 95% CI: -0.127, -0.011), that do not disinfect the navel of newborn calves (β -0.07, 95% CI: -0.133, -0.012), that allow transporters to enter the farm's building (β -0.07, 95% CI: -0.130, -0.015) and that used wood shaving as bedding for surplus calves (β -0.08, 95% CI: -0.156, -0.021). Sensitivity analyses performed on farms that have sold 2 or more surplus calves did not show significant changes in the associations found. Despite the fact that the study was based on self-reported questionnaire answers and a small number of calves per farm, it provides insight on farm management practices associated with median percentile of surplus calf selling price at the auction markets. Taking these results in consideration, farmers could potentially improve the market value of their animals.

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.

Lameness, primarily caused by hoof lesions, is a major concern for the dairy industry. While regular hoof trimming is widely used as part of prevention and treatment, its long-term effects are not fully understood. This retrospective study investigated 10 dairy farms in Southern Italy that transitioned from irregular (when cows showed signs of lameness or overgrown hooves) to regular hoof trimming (approximately every 6 mo in lactating cows) between 2016 and 2020. The first objective was to estimate the prevalence and types of hoof lesions. The second was to assess how lesion risk changed over time following the implementation of regular hoof trimming. Lesions were classified into 3 categories: infectious (INF), claw horn disruptive (CHD), and all lesions combined (ALL). Generalized additive mixed effect models (GAMMs) with a binomial family and logit link were fitted to model each lesion probability over time. A total of 14,438 individual-level inspections were performed (4,329 unique cows; 57,752 individual hooves) across 113 hoof trimming sessions, with a median time of 159 d (range: 36-338 d) between trimming sessions. Out of 4,329 unique cows inspected, 2,773 (64.1%) had at least one lesion during the study period; 38.0% (1,643/4,329) had at least one INF lesion and 47.0% (2,035/4,329) had at least one CHD lesion. The most common lesions were white line disease (59.4%) and digital dermatitis (58.2%). Lesion risk followed distinct temporal patterns: CHD lesions exhibited a nonlinear trajectory, declining from ~17% to ~7% by d 1000, then rising to ~10% after d 1500. INF lesions declined linearly from 15% to 5% over the same period. ALL lesions showed an early decline from ~30% to ~17-25% between d 500-1000, followed by stabilization. Seasonal variation was observed to have a modest but consistent effect, with predicted lesion risk modestly higher in winter months compared with summer months. Rear hooves consistently had higher predicted lesion risks than front hooves across all models. Substantial farm-level variability was also observed, highlighting the importance of tailored, herd-specific management approaches. In light of the observational study design, caution is required when interpreting these findings with respect to the hoof-trimming interval. Further research using controlled designs is warranted to optimize trimming protocols and identify additional risk factors.

An investigation at a large dairy farm was conducted in response to the farmer's concerns about a perceived increment in the prevalence of bovine digital dermatitis (BDD). An in‐parlour BDD scoring revealed an overall prevalence at foot level of 32%. The herd assessment included lesion analysis, evaluation of housing conditions and footbathing practices. The main risk factors were absence of BDD monitoring, delayed treatment, overstocking and inconsistency of the footbathing regimen. A control strategy focused on continuous monitoring by trained farm staff, prompt treatment of active lesions, and targeted adjustments to footbathing protocols. After 3 months, the prevalence of overall and the prevalence of active lesions decreased from 32% to 29% and from 24% to 16%, respectively. While challenges in maintaining the effectiveness of the footbath solution and managing cow flow persisted, these were addressed through proactive, adaptive management strategies, such as prompt identification and treatment of active lesions. This approach, focused on continuous monitoring, is key to achieving long‐term BDD control on farm.