Diagnostic and Prognostic Value of Clinical Scoring and Lung Ultrasonography to Assess Pulmonary Lesions in Veal Calves

SIMPLE SUMMARY: Respiratory disease in calves is often accompanied by an extensive usage of antimicrobial drugs. As part of the strategy to reduce antimicrobial resistance by “prudent use of antibiotics”, veterinarians and farmers need to ensure that individual therapy decisions are based on a “prior risk assessment” of the severity and prognosis of the respiratory disease. To achieve this goal, the integration of the on-farm diagnostic tool of ultrasonography and a simple clinical scoring system to evaluate the degree and severity of lung lesions is recommended. Our study highlights the importance of an early diagnosis of respiratory disease and shows that ultrasonography of the thorax is most useful in the early detection of lung tissue changes and should assist in prioritizing calf treatment and reducing the use of antibiotics. ABSTRACT: This study on veal calf respiratory disease assessed the association between an on-farm clinical scoring system and lung ultrasonography with the postmortem inspection of the lungs. The comparisons allowed the calculation of predictive values of the diagnostic methods. In total, 600 calves on an Austrian veal calf farm were examined at the beginning and the end of the fattening period. Overall, the area under the curve (AUC) for ultrasonographic scores was 0.90 (rsp = 0.78) with a sensitivity (Se) of 0.86. The specificity (Sp) was 0.78, and the positive predictive value (PPV) was 0.74. The AUC for the physical examination was 0.76 (rsp = 0.55) with a Se of 0.64, an Sp of 0.81, and a PPV of 0.69. For the combination of ultrasonography and physical examination, an AUC curve of 0.85 (rsp = 0.69) was calculated. A Se of 0.65 and a Sp of 0.88 with a PPV of 0.73 was calculated. This study concluded that both physical and ultrasonographic examination scoring are reliable examination methods for the detection of lung diseases in veal calves.