title: Developmental competence of HMC(TM) derived bovine cloned embryos obtained from somatic cell nuclear transfer of adult fibroblasts and granulosa cells.
abstract: To enable us to handle a large number of oocytes at a given time and to have an increased throughput of cloned embryos, we attempted the Handmade cloning (HMC) technique, a zona-free method of bovine somatic cell nuclear transfer. Our objective was to study the developmental competence of the HMC derived embryos obtained using different types of somatic cells. A total of 6,874 cumulus-oocyte-complexes were used with either 7th or 11th passage fibroblasts (1st and 2nd groups, respectively), which were prepared from male animals, or granulosa cells (3rd group) as nuclei donors. The average cleavage rate was 65%, accompanied by a blastocyst rate of just 2% for the cleaved products and 5% for the >8-cell embryos, and there was no significant difference between the three groups. Out of 27 blastocysts recovered, 22 blastocysts were transferred to 22 recipients, resulting in two pregnancies. One pregnancy was lost after the fourth week while the other progressed to full term with the birth of a male calf. This first successful cloning of a male calf with the HMC technique in Europe indicates the successful adoption and establishment of this technique in our laboratory, and that this technique can be successful in producing viable embryos.
authors.affiliation: Department of Reproductive Biology, Research Institute for the Biology of Farm Animals, Dummerstorf, Germany.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Bhojwani
authors.forename: Gabor
authors.initials: G
authors.lastname: Vajta
authors.forename: Henrik
authors.initials: H
authors.lastname: Callesen
authors.forename: Knut
authors.initials: K
authors.lastname: Roschlau
authors.forename: Andreas
authors.initials: A
authors.lastname: Kuwer
authors.forename: Frank
authors.initials: F
authors.lastname: Becker
authors.forename: Hannelore
authors.initials: H
authors.lastname: Alm
authors.forename: Helmut
authors.initials: H
authors.lastname: Torner
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Kanitz
authors.forename: Ralf
authors.initials: R
authors.lastname: Poehland
mesh_terms: D000818:Animals; D001724:Birth Weight; D001755:Blastocyst / Q000166:cytology; D002417:Cattle; D002453:Cell Cycle; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D019976:Cloning, Organism / Q000379:methods*; D046149:Embryo Culture Techniques; D004624:Embryo Transfer; D047108:Embryonic Development; D005260:Female; D005347:Fibroblasts / Q000166:cytology* / Q000378:metabolism; D006107:Granulosa Cells / Q000166:cytology*; D008297:Male; D009865:Oocytes / Q000166:cytology; D011247:Pregnancy; D011270:Pregnancy, Animal; D013997:Time Factors