Comparison of thoracic ultrasonography and thoracic radiography to detect active infectious bronchopneumonia in hospitalized dairy calves

Comparative diagnoses of respiratory disease in preweaned dairy calves using sequential thoracic ultrasonography and clinical respiratory scoring

AIMS

Bovine respiratory disease (BRD) has serious impacts on dairy production and animal welfare. It is most commonly diagnosed based on clinical respiratory signs (CRS), but in recent years, thoracic ultrasonography (TUS) has emerged as a diagnostic tool with improved sensitivity and specificity. This study aimed to assess the alignment of BRD diagnoses based on a Clinical Respiratory Scoring Chart (CRSC) and weekly TUS findings throughout the progression of BRD of variable severity in preweaned Holstein dairy heifers.

METHODS

A total of 60 calves on two farms were followed from the 2nd week of life through the 11th week of life and assessed on a weekly basis for CRS and lung consolidation via TUS. The alignment of BRD diagnoses based on CRSC scores and TUS findings was evaluated across disease progression (pre-consolidation, onset, chronic, or recovered) and severity (lobular or lobar lung consolidation) using receiver operator curves and area under the curves combined with Cohen's kappa (κ), sensitivity, and specificity.

RESULTS

The diagnosis of BRD using CRSC scores ≥5 aligned best with the onset of lobar lung consolidation (>1 cm in width and full thickness). This equated to an acceptable level of discrimination (AUC = 0.76), fair agreement (κ = 0.37), and a sensitivity of 29% and specificity of 99%. Similarly, there was acceptable discrimination (AUC = 0.70) and fair agreement (κ = 0.33) between CRSC ≥5 and the onset of a less severe threshold of disease based on lobular (1-3 cm2 but not full thickness) or lobar consolidation. Discrimination remained acceptable (AUC = 0.71) with fair agreement (κ = 0.28) between CRSC scores ≥2 for nasal discharge and/or cough (spontaneous or induced) and the onset of lobar consolidation. However, sensitivity was <40% across comparisons and outside of the onset of disease there tended to be poor discrimination, slight agreement, and lowered sensitivity between CRS and TUS diagnoses of lobular or lobar consolidation (pre-consolidation, chronic, or recovered). Conversely, specificity was relatively high (≥92%) across comparisons suggesting that CRSC diagnoses indicative of BRD and associated lung consolidation tend to result in few false positive diagnoses and accurate identification of healthy animals.

CONCLUSIONS AND CLINICAL RELEVANCE

Although we found the specificity of clinical signs for diagnosing lung consolidation to be ≥92% across all methods of TUS evaluations, the low levels of sensitivity dictate that clinical assessments lead to many false negative diagnoses. Consequently, depending on clinical signs alone to diagnose BRD within populations of dairy calves will likely result in overlooking a substantial proportion of subclinically affected animals that could inform the success of treatment and prevention protocols and guide management decisions.

Literature Review of the Principal Diagnostic Tests to Detect Bovine Respiratory Disease in Pre-Weaned Dairy and Veal Calves

Bovine respiratory disease (BRD) is an infection of the upper and lower respiratory tract, characterized by an inflammation of the lung. Different diagnostic tests can be used to detect BRD, including clinical respiratory scoring systems, thoracic auscultation, and imaging tests like thoracic ultrasonography and thoracic radiography. Although commonly used, none of these diagnostic tests are perfect for detecting BRD. This article reviews the advantages and drawbacks of these techniques and their performance in detecting BRD in pre-weaned dairy and veal calves.

Remimazolam attenuates inflammation in bronchopneumonia through the inhibition of NLRP3 activity by PDPK1 ubiquitination

Bronchopneumonia is the most common pneumonia in childhood. Therefore, we tested the effects of Remimazolam presented Bronchopneumonia and its possible mechanisms. Phillygenin increased survival rate, reduced W/D ratio, and lung injury score, and inhibited IL-1β, IL-6, TNF-α, and INF-γ levels in mice model of bronchopneumonia. Remimazolam induced PDPK1 and p-AKT protein expressions, and suppressed NLRP3 protein expression in lung tissue of mice model. In vitro model, Remimazolam also induced PDPK1 and p-AKT protein expressions, and suppressed NLRP3 protein expression. Remimazolam also inhibited inflammation levels in vitro model. PDPK1 inhibitor, PHT-427 (100 mg/kg) reduced survival rate, increased W/D ratio and lung injury score, and promoted inflammation levels in mice model of bronchopneumonia by treated with Remimazolam. PHT-427 suppressed PDPK1 and p-AKT protein expressions and induced NLRP3 protein expression in mice model of bronchopneumonia by treated with Remimazolam. Remimazolam interlinked PDPK1 protein. Remimazolam increased the expressions of PDPK1 and p-AKT in vitro model. Remimazolam reduced PDPK1 ubiquitination in vitro model.

Using Machine Learning and Behavioral Patterns Observed by Automated Feeders and Accelerometers for the Early Indication of Clinical Bovine Respiratory Disease Status in Preweaned Dairy Calves

The objective of this retrospective cohort study was to evaluate a K-nearest neighbor (KNN) algorithm to classify and indicate bovine respiratory disease (clinical BRD) status using behavioral patterns in preweaned dairy calves. Calves (N=106) were enrolled in this study, which occurred at one facility for the preweaning period. Precision dairy technologies were used to record feeding behavior with an automated feeder and activity behavior with a pedometer (automated features). Daily, calves were manually health-scored for bovine respiratory disease (clinical BRD; Wisconsin scoring system, WI, USA), and weights were taken twice weekly (manual features). All calves were also scored for ultrasonographic lung consolidation twice weekly. A clinical BRD bout (day 0) was defined as 2 scores classified as abnormal on the Wisconsin scoring system and an area of consolidated lung ≥3.0 cm2. There were 54 calves dignosed with a clinical BRD bout. Two scenarios were considered for KNN inference. In the first scenario (diagnosis scenario), the KNN algorithm classified calves as clinical BRD positive or as negative for respiratory infection. For the second scenario (preclinical BRD bout scenario), the 14 days before a clinical BRD bout was evaluated to determine if behavioral changes were indicative of calves destined for disease. Both scenarios investigated the use of automated features or manual features or both. For the diagnosis scenario, manual features had negligible improvements compared to automated features, with an accuracy of 0.95 ± 0.02 and 0.94 ± 0.02, respectively, for classifying calves as negative for respiratory infection. There was an equal accuracy of 0.98 ± 0.01 for classifying calves as sick using automated and manual features. For the preclinical BRD bout scenario, automated features were highly accurate at -6 days prior to diagnosis (0.90 ± 0.02), while manual features had low accuracy at -6 days (0.52 ± 0.03). Automated features were near perfectly accurate at -1 day before clinical BRD diagnosis compared to the high accuracy of manual features (0.86 ± 0.03). This research indicates that machine-learning algorithms accurately predict clinical BRD status at up to -6 days using a myriad of feeding behaviors and activity levels in calves. Precision dairy technologies hold the potential to indicate the BRD status in preweaned calves.

Comparison of thoracic ultrasonography and thoracic radiography to detect active infectious bronchopneumonia in hospitalized dairy calves

Background

The best test between thoracic ultrasonography (TUS) and thoracic radiography (TR) or the best combination of tests (series or parallel) to detect active infectious bronchopneumonia (BP) in hospitalized dairy calves remains unknown.

Hypothesis/Objectives

To estimate performances of TUS and TR to detect active BP in hospitalized dairy calves and to determine the best strategy for using these tests based on a panel diagnosis method (PDM). Performances of TUS and TR were hypothesized to be equivalent.

Animals

Fifty hospitalized dairy calves (≥7 days old; ≤100 kg; standing; pCO₂ ≥ 53 mm Hg; any reason of presentation).

Methods

Each calf prospectively and sequentially underwent physical examination, thoracic auscultation, blood analyses, and TUS and TR. Three blinded experts determined whether active BP was present/absent based on PDM. Krippendorff's alpha measured interexpert agreement. The sensitivities (Se) and specificities (Sp) of TUS and TR alone and in series or parallel were compared (McNemar's test; P < .05).

Results

Interexpert agreement was moderate at 0.58 (95%CI: 0.42; 0.73). The Se and Sp of TUS were 0.84 (95%CI: 0.60; 0.97) and 0.74 (95%CI: 0.57; 0.86), respectively. The Se and Sp of TR were 0.89 (95%CI: 0.67; 0.99) and 0.58 (95%CI: 0.39; 0.75), respectively. No significant difference was found in the Se and Sp of TUS and TR when analyzed alone, in series or in parallel.

Conclusion

Thoracic ultrasonography or TR alone equally detected active BP in hospitalized dairy calves. Series or parallel analysis provided no additional benefit. Its ease of use and widespread accessibility support using TUS as a first‐line test to detect active BP in hospitalized dairy calves.