AbstractAnalysis of cellular effector function(s) of ten requires their isolation from other cellular types. Cel1 separatory techniques could mask, or select Out, clinically important functional lesions. We examined differences in canine peripheral blood neutrophil functions, i.e. migration and H2152 production, following two commonly used cell separation techniques: isotonic lysis. or density gradient (Percoll) centrifugation. Separation methodology was observed to have a significant impact on both metatlolic and mobility functions. In comparison to isotonic lysis, Percoll separation caused near 100% increases in random migration, near 40% decreases in chemotaxis and 70% Increases in H202 production.