Student Case Presentation
Acute Onset of Respiratory Distress in an Adult Charolais Cow
| Date/Time: |
8/27/2026 Poster 05
|
| Presenter: |
Antonio Silva |
| Veterinary School: |
TAM |
Abstract:
A 5-year-old Charolais cow presented to a referring veterinarian for acute onset of respiratory distress and lethargy of 12 hours duration. The cow was treated with tulathromycin and ketoprofen and discharged back to the client. The next morning, the cow’s condition deteriorated further, and she was referred to a tertiary care center. Additional information obtained from the owner revealed that five other adult cows from the herd had died with similar clinical signs over the past 18 months, and that the herd was regularly rotated through three different pastures, from low-quality to high-quality forage. Physical examination findings included a rectal temperature of 105° F, bilateral nasal discharge, open-mouth breathing, tachypnea, expiratory grunt, increased bronchovesicular sounds bilaterally, frothing at the mouth, and decreased to absent rumen contractions. Differential diagnoses prior to further diagnostic investigation included atypical interstitial pneumonia and severe bronchopneumonia. Significant abnormalities noted in the complete blood count and serum chemistry included dehydration and markedly elevated globulins. Thoracic radiographs revealed a severe, diffuse, patchy interstitial to multifocally alveolar pulmonary pattern with concurrent thickened borders of small airways. Due to the lack of response to prior antimicrobial and anti-inflammatory therapy, along with the history and clinical signs, our primary differential was atypical interstitial pneumonia triggered by the movement of this cow from low-quality to high-quality forage pasture. Despite the initiation of aggressive therapy, including nebulization with albuterol and tulathromycin, the cow died the first night. Gross postmortem findings indicated lung changes consistent with atypical interstitial pneumonia, which was later confirmed by histopathology. Rotating grazing pastures to maintain consistent provision of adequate nutrition to cattle is common. However, this case highlights the care needed to ensure receiving pastures are not enhanced excessively, creating a large disparity in forage quality when moving cattle from low-quality to high-quality forage pasture.
