Abdominocentesis in cattle: technique and criteria for diagnosis of peritonitis.

A reliable method for the collection of peritoneal fluid from cattle using a trocar and cannula is described. Peritoneal fluid was collected from three groups of cattle: periparturient, normal and with peritonitis. The fluid was examined by white cell count, differential cell count, total protein concentration and bacteriology. The results were analysed to determine the best criteria for peritonitis. Greater than 10% eosinophils were typical of normal peritoneal fluid. Peritoneal fluid with a relative neutrophil count greater than 40% and a relative eosinophil count of less than 10% was frequently associated with the diagnosis of peritonitis. Parturient cattle had large volumes of peritoneal fluid with low total protein and white cell counts. Growth of Gram-negative or anaerobic organisms was associated with mortality.