Effect of the Bovine Oviductal Fluid onIn VitroFertilization, Development and Gene Expression ofIn Vitro-Produced Bovine Blastocysts

Oviductal microenvironment generally provides better condi-tions for early embryo development than the conventionalin vitro system. In an attempt to simulate the oviductconditions or the main potentially influencing factors, theeffect was studied of a bovine oviductal fluid (bOF) treatmentapplied prior to IVF on (i) IVF parameters, (ii) cleavage rate,(iii) blastocyst yield and (iv) blastocyst quality. Embryo qualitywas assessed by morphological embryo quality and relativetranscript abundance of several developmental genes in bovineblastocysts. Furthermore, to study the effect of bOF withoutthe male effect and zona–sperm interaction, artificially acti-vated metaphase II oocytes were also treated w…