Percentage of apoptotic peripheral bovine PMNs incubated for 2 h with either 1× PBS (CON), 0.5 μg of tilmicosin per ml (TIL), 0.5 μg of penicillin per ml (PEN), 0.5 μg of ceftiofur per ml (CEF), 0.5 μg of oxytetracycline per ml (OXY), or 10−8 M dexamethasone (DEX). Values are means ± standard errors of the means; n = 5 per experimental group. ∗∗, P < 0.01 versus control.