Comparison of Diagnostic Methods for Respiratory Disease in Calves Used on Farms With Thoracic Radiography

The most commonly used techniques in the field are the pulmonary auscultation, Wisconsin score (WI), California score (CA), and pulmonary ultrasonography. However, with the exception of the latter, no studies have compared thoracic radiography with other possible techniques in calves. Therefore, the objective of the study was to compare and verify the agreement between clinical score techniques, pulmonary auscultation, and ultrasonographic and radiographic evaluations, considering the latter as reference test. Thirty-three calves were evaluated from 17 to 60 days of age using pulmonary auscultation, Wisconsin score (WI), California score (CA), thoracic radiography, and pulmonary ultrasonography at five preestablished moments and at any time when presenting clinical respiratory disease. Of the 160 evaluations, 21% were positive for thoracic radiography, 21% for ultrasonography, 10% for pulmonary auscultation, 16% for CA score, and 14% for WI score. In the concordance analysis, there was a moderate correlation between thoracic radiography and ultrasonography (k = 0.6035) and between pulmonary auscultation and WI score (k = 0.5833) and CA score (k = 0.5277), and substantial between the WI and CA score methods (k = 0.7258). All techniques used in the study were useful for the diagnosis of pneumonia; however, due to high accuracy and practicality, ultrasonography proved to be an interesting method to be implemented on farms.