EN
Early bovine embryos (two -to sixteen blastomers) produced in vitro were cytogenetically analysed to determine the incidence of haploidy.Follicular oocytes were matured in vitro and inseminated with sperm prepared using the swim up method.After 2-3 days of culture, chromosome slides were prepared according to the air-drying technique and stained with Giemsa.Altogether 202 embryos produced mathaphase spreads.Of these 4.5% were pure haploid embryos and 5.5% displayed a haploid cell line within mosaic embryos (n/2n and n/3n).The occurence of haploid embryos observed in this study was compared to results of other studies and a possible origin of haploidy was discussed.