RESUMEN
Metabolic changes were studied in the serum, saliva and peritoneal fluid of 5 healthy yearling feedlot steers after experimentally induced urinary bladder rupture. There were statistically significant decreases in serum, saliva and peritoneal fluid sodium and chloride values and significant increases in serum, saliva and peritoneal fluid urea nitrogen, creatinine and phosphorus values. Serum calcium, pH, bicarbonate, and base excess decreased significantly. Potassium did not change significantly in serum but did increase significantly in the saliva. The hemogram and peritoneal fluid analysis failed to provide clinicopathologic evidence of peritonitis. The average time of death or euthanasia after bladder rupture was 13.6 days with a range of 8-21 days. No single biochemical parameter could be identified which would allow prediction of the approaching time of death or duration of the disease process. There was no peritonitis at necropsy indicating that urine was not irritating to the bovine peritoneal cavity. Extracellular replacement fluid with or without sodium bicarbonate supplementation appeared to be the fluid of choice for correction of fluid and electrolyte imbalances in steers with ruptured urinary bladders. The ratio between serum and peritoneal fluid creatinine concentrations appears to be valuable for the clinical diagnosis of ruptured urinary bladders in steers.