Thymic and mammary lymphosarcoma in a three-year-old heifer.

Ventral edema, dyspnea, fever, tachycardia, bloat and muffled heart sounds were identified in a 3-year-old heifer. Attempts to relieve the bloat by passing an orogastric tube were unsuccessful. The heifer was bovine leukemia virus-negative by the agar gel immunodiffusion test, and had normocytic, normochromic anemia, mature neutrophilia, and hyperproteinemia. Pleural effusion was identified by thoracic ultrasonography. Cytologic examination of pleural fluid revealed an increased number of atypical lymphocytes. The heifer died, and at necropsy, thymic and metastatic mammary lymphosarcoma was confirmed.