A pilot study has been carried out in North East Scotland by the Scottish Agricultural College (SAC) Aberdeen, Buchan Meat and Animal Biotechnology Cambridge (ABC), transferring in-vitro fertilised (IVF) bovine embryos to cattle in commercial diary and suckler herds. The pilot study was undertaken with the co-operation of veterinary practices in the area.
The embryos were produced entirely in-vitro, using ovaries removed from beef heifers post slaughter as a source of oocytes. The heifers were selected pre and post slaughter for breed, health, conformation and fatness. The oocytes were allowed to mature for 24 hours and then fertilised using frozen/thawed semen from top quality beef bulls. These sires were selected for breed, ease of calving, conformation, growth and ability to fertilise in-vitro. Forty-eight hours after insemination the developing embryos were transferred to a co-culture system. After 4 to 5 days of culture the embryos had developed to the morula/blastocyst stage, and were ready for transfer. The recipients’ oestrus cycles were synchronised using a combined PRID and prostaglandin programme. The PRID was inserted on day 1 of the programme and withdrawn on day 9 or day 10 of the programme.