Neutrophil responses were evaluated in dairy cows at parturition and on 1, 2, 3, 5 and 7 days after they were given dihydroheptaprenol (DHP) (0.5 mg/kg body weight) at parturition. The chemiluminescent index increased significantly (P < 0.05) from parturition to 1 day after parturition in cows injected with DHP. No significant differences were observed in the number of neutrophils between untreated and DHP-treated groups of dairy cows during the immediate postparturient period.