4 What’s the process? Superovulation Insemination Donor female is stimulated to ovulate more than one egg/cycleHormones are injected to cause superovulationInseminationThe donor cow (the cow superovulated) is bred
5 Common hormones used for superovulation PMSG (pregnant mare’s serum gonadotropin)FSH (follicle stimulating hormone)eCG (equine chorionic gonadotrophin)Prostaglandin F2 alphaLH (luteinizing hormone)
6 What’s the process? 3. Ova Collection (Flushing) Nonsurgical: rubber catheter inserted through cervixsaline solution flushed into and out of uterusharvests the embryos 7-8 days after estrus30 minute or less procedurestandard method
7 Click HERE if video does not play Flushing processClick HERE if video does not play
8 What’s the process? 4. Evaluation of the Embryos Regularity of shape of the embryoCompactness of the blastomeresVariation in cell sizeColor and texture of the cytoplasmBlastomeres: the dividing cells within the boundaries of the embryoCytoplasm: the fluid within the cell wall
9 What’s the process? 4. Evaluation of Embyo’s cont. Overall diameter of the embryoPresence of extruded cells and vesiclesRegularity of the zona pellucidaZona pellucida: the protective layer of protein and polysaccharides around the single celled embryoVesicles: small bubble-like structures in the cytoplasm
10 Embryo Classification Grades:Grade 1: Excellent or GoodGrade 2: FairGrade 3: PoorGrade 4: Dead or degenerating
11 Embryo Classification Stage of Development:Stage 1: UnfertilizedStage 2: 2 to 12 cellStage 3: Early morulaStage 4: MorulaStage 5: Early BlastocystStage 6: BlastocystStage 7: Expanded BlastocystStage 8: Hatched BlastocystStage 9: Expanding Hatched Blastocyst
12 What’s the process? 5. Implantation Recipient cows must be at right stage in estrous cycle to receive embryoRecipient cows are synchronized with donorThe eggs are transferred to the recipient cows
13 Quick! What are the five processes of Embryo Transfer?
14 Benefits of Embryo Transfer A dozen calves might be obtained from a valuable cow in one yearThe rate of genetic improvement would quickenProgeny testing of heifers can be done quickerGenetically inferior animals could be made more productive by using them as recipient animals
15 Benefits of Embryo Transfer Large numbers of fertilized eggs can be transferred from young heifersLarge amount of fertilized eggs can be transferred into mature recipientsValuable cows that fail to conceive due to hormonal defects would not need to be culled
16 Limitations Expensive The technique for harvesting the ova is complicatedDonors used repeatedly may become incapable of carrying to full term
17 FFA/SAE and Career opportunities Bred replacement heifer for the fairEmbryologistInternship with veterinarianVeterinarian tech/ VeterinarianIn-vitro fertilization at a DairyEmbryo transfer technician
18 Are there any limitations to using frozen embryos? What do you think has better pregnancy rates, embryos transferred that were frozen or fresh?Are there any limitations to using frozen embryos?