IVF vs. conventional flush: producing embryos to sell
By the RanchOS Global editorial team · Updated
In short: conventional flushing (MOET) produces embryos that freeze and travel well, which suits selling embryos to other ranches. IVF gets more out of scarce semen and difficult or pregnant donors, but its embryos survive freezing less well, so they are more often transferred fresh. Many programs use both.
How each works
- Conventional flush (MOET): the donor is superovulated with hormone injections, inseminated, and the embryos are flushed from the uterus about seven days later.
- IVF: eggs are collected from the donor's ovaries by ultrasound-guided aspiration (ovum pick-up), then matured, fertilized and grown in a lab.
How they compare
| Conventional flush (MOET) | IVF | |
|---|---|---|
| Embryos | About 6.9 viable embryos per flush on average in beef females, with wide variation | Depends on eggs collected; collection can be repeated two to three times per cycle |
| Semen use | More semen per donor than IVF | One straw can fertilize hundreds of eggs |
| Donors | Needs a donor that responds well to superovulation | Works for poor responders and for donors that are already pregnant |
| Pregnancy rate | Higher; fresh embryos 10% to 15% higher than frozen | About 10% lower than MOET, with more pregnancy losses |
| Freezing | Embryos freeze well, so they can be stored and shipped | Embryos lose more viability when frozen, so they are more often transferred fresh |
Figures are from a Progressive Cattle review by Nicky Oosthuizen and G. Cliff Lamb. Results vary with breed, age and the individual cow; ask your embryo transfer practitioner for their own numbers.
What this means for selling
- Selling frozen embryos to other ranches: MOET embryos are the usual choice because they hold up better after freezing.
- Rare or expensive semen: IVF stretches each straw much further.
- Your best donor is pregnant or does not flush well: IVF can keep her producing.
- Registration: check your association's rules for donor dams and AI sires before you sell. For example, the American Simmental Association requires a DNA panel for donor dam approval, and the American Angus Association requires DNA on file for AI sires.
What to put in an embryo listing
Donor and sire with registration numbers, both pedigrees and EPDs, how the embryos were produced (flush or IVF), grade and stage if your practitioner records them, number available, price per embryo or per lot, storage and shipping terms, and any guarantee.
See also How to sell bull semen and embryos online. On RanchOS Global, donor cows carry their embryo availability on their own page.