Cr. Looney et al., COMMERCIAL ASPECTS OF OOCYTE RETRIEVAL AND IN-VITRO FERTILIZATION (IVF) FOR EMBRYO PRODUCTION IN PROBLEM COWS, Theriogenology, 41(1), 1994, pp. 67-72
Ultrasound-guided follicular aspiration and in vitro embryo production
techniques were employed to retrieve oocytes and produce embryos from
200 problem donor female cattle who had not been successful in conven
tional embryo production. Weekly oocyte retrieval resulted in an avera
ge of 6.3 oocytes per aspiration and FSH stimulation for 3 days prior
to oocyte retrieval increased the oocyte retrieval rate to 8.6 oocytes
per aspiration. In total 1,006 retrieval sessions were performed and
9,120 follicles were aspirated and 6,344 oocytes were retrieved (69.6%
). IVF procedures were carried out on 5,986 oocytes and produced 2,677
cleavage stage embryos (44.7%) and 984 viable embryos (16.4%) of whic
h 813 transfers were made and 325 pregnancies were detected (40%). Ult
rasound-guided follicular aspiration and IVF was successful in produci
ng pregnancies from previously non-productive problem donors.