Pleural effusion was examined from a 5-year-old, female Brittany Spaniel with a 7-day history of dyspnea, anorexia, and diarrhea. The fluid was yellow, cloudy, and slightly gelatinous, and had a total protein concentration of 2.8 g/dL, a total nucleated cell concentration of 1.1 x 10(3)/microL, and