The aim of the present study was to determine and characterize the clinical, hematological, biochemical parametersand outcome in cows suffering from Omaso-abomasal volvulus (OAV). Animals data were obtained from medicalrecords of 60 adult dairy cattle suffering from OAV (Clinic for Ruminants, Justus-Liebig-University, Germany).For each case, history, age, results of clinical examination, hematological and biochemical findings were recordedand analyzed. Ages of animals were between 2.3 and 8 years, (mean 4.8). Compared with the respective normalrange, there were significant increases of the heart rate, hematocrit, total bilirubin, urea blood, concentrations ofbicarbonate and base excess. Serum chloride and potassium were significantly decreased in the majority of cows.In this study, dehydration, metabolic alkalosis, hypochloremia, hypokalemia and circulatory insufficiency werethe major common findings in cows with Omasum-abomasal volvulus. Excessive stretching of the abomasal walland long lasting strangulations at the torsion-sites must be avoided (surgery should be performed as soon afterdiagnosis of AOV as possible) and correction of these conditions with aggressive intravenous fluid therapy isnecessary before the surgical intervention for correction of the hematobiochemical alterations