Effects of fetal calf serum (FCS) or bovine serum albumin (BSA), with or without vitamin E (vit. E) or phenazine ethosulfate (PES) supplementation on developmental competence and quality of cultured porcine embryos were examined. The experiment was done on zygotes and 2-cell embryos obtained from superovulated gilts. Morphologically normal zygotes were cultured in vitro in NCSU-23 medium supplemented with: experiment 1-0.004 g/ml BSA, 10% FCS, protein-free (control); experiment 2-0 (control), 25, 50 or 100 M vit. E; experiment 3-0 (control), 0.025, 0.05 or 0.075 M PES. Embryo quality criteria were developmental competence (cleavage, morula and blastocyst rates), total cell number per blastocyst and degree of apoptosis as assessed by TUNEL staining. Presence of BSA in culture medium increased significantly morula and blastocysts production as compared to FCS (P<0.001) and protein-free group (P<0.05 and P<0.001, respectively). The blastocysts cultured in protein-free medium had higher average number of apoptotic nuclei and DNA fragmented nucleus index as compared to the BSA (P<0.05 and P<0.01, respectively) and FCS (P<0.5) group. Supplementation in culture medium of 100 M vit. E increased blastocyst production as compared to control and 50 M vit-E (P<0.05). Both the number of cells per and percentage of TUNEL positive nuclei per blastocyst were slightly lower in PES treated than control groups.