Hemotherapy using whole blood and its components is being increasingly used in veterinary therapy. Since it is important to store animal blood while maintaining acceptable hematological, blood gas, and biochemical characteristics, increasing our knowledge of available technologies for strategic blood storage is imperative. Thus, we aimed to assess the hematological, blood gas, and biochemical changes in donkey whole blood using blood bags with two different types of storage agents. Eight adult healthy male donkeys were used; 900 mL of blood was collected from each, with 450 mL stored in citrate-phosphate-dextrose and adenine bags (CPDA-1) and 450 mL stored in bags containing citrate-phosphate-dextrose, adenine, mannitol, and sodium chloride (CPD/SAG-M). Both bags were kept refrigerated between 1 and 6 °C for 42 days. Blood samples were removed from the bags eight times (T): T0 (immediately after blood collection), T1, T3, T7, T14, T21, T35, and T42 (1, 3, 7, 14, 21, 35 and 42 days after storage). Hematological, blood gas, biochemical, and microbiological parameters were assessed. The CPDA-1 bags had a higher packed cell volume when compared to CPD/ SAG-M. The red blood cell count reduced by around 19% in both the bags due to hemolysis, which was confirmed by an increase in plasma hemoglobin. The white blood cell count; pH; concentrations of glucose, sodium, bicarbonate, and 2,3 diphosphoglycerate were reduced in both bags. Meanwhile, pO2, pCO2, lactate dehydrogenase, and levels of potassium increased in the CPDA-1 and CPD/SAG-M bags. Blood bags were efficient for the storage of donkey blood for up to 42 days.