NAVLE® Question of the day

MO TU WED TH FR
August 18, 2025
NAVLE

A four-month-old filly is presented with a four-day history of lethargy, heavy breathing, cough, and decreased appetite.

ValueNormal
104.9°F (40.5°C)99.0–100.6°F (37.2–38.1°C)
HR=72 bpm28-40 bpm
R=44 brpm10-14 brpm

Lung auscultation reveals asymmetrically distributed crackles and wheezes bilaterally. Some areas have no breath sounds and a dull resonance on thoracic percussion. A lateral chest radiograph shows consolidated nodular lung lesions and mediastinal lymphadenopathy.

Pneumonia due to Rhodococcus equi  infection is confirmed based on culture and polymerase chain reaction results on a tracheal wash. 

Which one of following choices is the most appropriate treatment?