Abstract
The objectives of this study were to isolate bacteria from in vitro fertilized (IVF) bovine embryo product system with or without antibiotics (penicillin + streptomycin) and to determine whether bacterial contamination affected the development of IVF embryos. 101 to 103 colony forming units (CFU)/ml of bacteria were isolated from transport medium and wash medium with antibiotics of slaughterhouse derived ovaries, but no bacteria were recovered from subsequent wash medium of oocytes and in vitro culture medium. In contrast, 101 to 106 CFU/ml of bacteria were isolated from all media without antibiotics used in IVF embryo product system. The bacteria isolated from transport medium were mainly gram negative rods and resistant to antibiotics of penicillin, macrolide, tetracyclin and cephem line. The rates of cleavage and development to blastocysts of IVF embryos produced in IVF embryo product system with antibiotics were significantly higher than without antibiotics. It was concluded that effective antibiotics should be added to IVF bovine embryo product system for removing or killing bacteria adhered to ovaries, oocytes or embryos.
