Early embryo development is known to be impacted by its environment and especially by oviductal secretions in vivo. In cattle, embryo co-culture with bovine oviduct epithelial cells (BOEC) has thus been developed to mimic the in vivo oviduct/embryo crosstalk. Neverthe-less, to the best of our knowledge, whether BOEC had a specific impact on embryo transcrip-tome hasn’t been investigated yet. To answer this question, we compared bovine blastocysts obtained by co-culture with BOEC to blastocysts obtained with another co-culture system: VERO cells (an epithelial cell line derived from monkey kidney). Control blastocysts were obtained in standard conditions, i.e. at 5% O2 in SOF medium (Minitüb, Tiefenbach, Germa-ny) + 5% Fetal Calf Serum (FCS). Because co-culture systems require 20% O2 to maintain feeder cells alive, embryos cultured at 20% O2 in SOF + 5% FCS were included as an addi-tional control. Cleavage rates and timing of blastocyst appearance were similar in the four culture conditions. A significant decrease in blastocyst rate was observed at 20% O2 without feeder cells. Day 8 blastocysts transcriptome was analyzed on a new customized bovine mi-croarray including more than 26 700 transcripts and 250 retroviral ESTs (GEO platform GPL21734). Hierarchical clustering of the samples revealed very weak differences between culture conditions but a clear clustering of samples depending on the presence or absence of feeder cells. Considering an adjusted P value 2 (Limma test), 36 transcripts were found diffe-rentially expressed between blastocysts obtained in SOF medium in 5% or 20% O2. Compa-ring the two co-culture conditions revealed only 10 differentially expressed transcripts sug-gesting almost no difference induced by the origin of cells used in co-culture systems on bo-vine blastocyst transcriptome. Nevertheless, the presence of BOEC or VERO cells induced differential expression of 192 and 229 transcripts respectively when compared to 5% O2 and 542 and 881 transcripts respectively when compared to 20% O2. A large proportion of the transcripts affected by co-culture with BOEC were also impacted by VERO cells. Several biofunctions relative to cell cycle regulation, free radical scavenging and glucose and lipid metabolism were impacted by both cell types when compared to culture in SOF without fee-der cells. Collectively, co-culture systems, using BOEC or VERO cells, do not improve clea-vage and blastocyst rates and induce weak and closely related modifications of blastocyst transcriptome when compared to 5% O2 culture condition in SOF medium.