Targeted thoracic ultrasonography shows high diagnostic potential for interstitial pneumonia in feedyard cattle.

OBJECTIVE

To use a novel approach of targeted thoracic point-of-care ultrasound (TT-POCUS) of the caudodorsal right lung to determine potential associations between TT-POCUS measurements and the presence of interstitial pneumonia (IP) in feedyard cattle.

METHODS

Cross-sectional study evaluated feedyard animals (n = 62; 358.4 ± 10.5 kg; heifer, n = 38; steer, n = 24) using TT-POCUS at time of respiratory disease treatment and microscopic assessment of lesions at subsequent mortality. Evaluations took place from July through December 2023. Pulmonary samples were collected at necropsy for histopathologic assessment, and lesions were used to diagnose IP or non-IP. Statistical models determined potential associations between IP, cattle demographic, and TT-POCUS measured variables.

RESULTS

Evaluations of animals enrolled (n = 62) displayed significant associations with IP, including ultrasound lung score (ULS), B-line count, A-line count, and days on feed at treatment. Cattle with a ULS of 5 had the lowest probability of IP (0.12 ± 0.16) compared to cattle with a ULS of 2, 3, or 4 (0.72 ± 0.18, 0.93 ± 0.06, and 0.85 ± 0.08, respectively). Cattle with B-line counts > 5 had a higher probability of IP (0.86 ± 0.11) compared to cattle with 3 to 5 B-lines (0.38 ± 0.14). The probability of IP was higher in cattle with A-line counts < 3 (0.83 ± 0.10) compared to cattle with ≥ 3 A-lines (0.51 ± 0.15).

CONCLUSIONS

Strategic targeted thoracic ultrasonography has potential a value of timely IP diagnosis in feedyard cattle, thereby offering important insights into therapeutic and management decisions.

CLINICAL RELEVANCE

Targeted thoracic ultrasonography can be utilized as a method for IP diagnosis in feedyard cattle.