Adherence of chicken heterophils was evaluated at 37 C using preconstructed columns containing various weights of nylon fiber (75 mg, 100 mg, or 125 mg) and whole blood anticoagulated with sodium heparin or 10% disodium ethylenediamine tetraacetic acid (EDTA). Additionally, 50-mg and 75-mg nylon fiber columns incubated at 41 C were used to evaluate heterophil adherence at an increased temperature. The mean percent adherence for heparin-anticoagulated blood applied to 75-mg, 100-mg, and 125-mg nylon fiber columns at 37 C was 76%, 92% and 97.4%, respectively. Samples applied to 50-mg and 75-mg columns at 41 C had adherence values of 27% and 85%, respectively. When paired samples of blood anticoagulated with EDTA or heparin were evaluated, the EDTA samples had significantly decreased heterophil adherence (paired t-test). Results indicate that increased or decreased adherence of chicken heterophils would best be detected using 75-mg nylon fiber columns incubated 37 C and whole blood collected in sodium heparin.