Pig and Cow Blood During Cold Storage in CPDA‐1 Solution: Hematology and Fluid Behavior

Nature provides red blood cell types (RBCs) with diverse mechanical properties, making possible to examine native blood in the presence of different RBC properties (size, shape, aggregability, deformability) without chemically changing the cell membranes, and without modifying the surrounding plasma. We investigated whether the shelf life of cow blood (stiff RBCs, low aggregability) is longer compared to pig blood (deformability/aggregability comparable to human) during cold storage due to a delay in RBC clustering and decomposition. Blood was drawn from conscious pigs and cows (CPDA-1) in their familiar environment to reduce stress, and stored 30 days at +7°C. RBCs remained intact in cow samples whereas pig samples became hemolytic after day 20. White blood cells and platelets decreased with similar percentage in both species. Hematocrit (HCT) decreased due to RBC shrinking in bovine, and due to RBC decay in porcine samples. Blood viscosity increased in both species although HCT decreased. In porcine samples shear-thinning decreased progressively, indicating gradual loss of sample cohesion with storage time. Also, yield stress and storage modulus decreased with hemolysis. In cow samples shear-thinning, yield stress, and storage modulus showed high intraindividual variability, but the mean values did not change over the time course.