Presentation on theme: "Got Babies? Embryo Transfer in Livestock CLF3256 Kati Chamberlin - AgEd 410, Spring 2013."— Presentation transcript:
Got Babies? Embryo Transfer in Livestock CLF3256 Kati Chamberlin - AgEd 410, Spring 2013
Introduction What is embryo transfer? Removing fertilized eggs from a donor and placing them in a recipient female Most common in beef and dairy cattle Also known as ova transplantation
How does it work?
Whats the process? 1.Superovulation Donor female is stimulated to ovulate more than one egg/cycle Hormones are injected to cause superovulation 2.Insemination The donor cow (the cow superovulated) is bred
Common hormones used for superovulation PMSG (pregnant mares serum gonadotropin) FSH (follicle stimulating hormone) eCG (equine chorionic gonadotrophin) Prostaglandin F 2 alpha LH (luteinizing hormone)
Whats the process? 3. Ova Collection (Flushing) Nonsurgical: rubber catheter inserted through cervix saline solution flushed into and out of uterus harvests the embryos 7-8 days after estrus 30 minute or less procedure standard method
Flushing process Click HERE if video does not play
Whats the process? 4. Evaluation of the Embryos Regularity of shape of the embryo Compactness of the blastomeres Variation in cell size Color and texture of the cytoplasm
Whats the process? 4. Evaluation of Embyos cont. Overall diameter of the embryo Presence of extruded cells and vesicles Regularity of the zona pellucida
Embryo Classification Grades: Grade 1: Excellent or Good Grade 2: Fair Grade 3: Poor Grade 4: Dead or degenerating
Whats the process? 5. Implantation Recipient cows must be at right stage in estrous cycle to receive embryo Recipient cows are synchronized with donor The eggs are transferred to the recipient cows
Quick! What are the five processes of Embryo Transfer?
Benefits of Embryo Transfer A dozen calves might be obtained from a valuable cow in one year The rate of genetic improvement would quicken Progeny testing of heifers can be done quicker Genetically inferior animals could be made more productive by using them as recipient animals
Benefits of Embryo Transfer Large numbers of fertilized eggs can be transferred from young heifers Large amount of fertilized eggs can be transferred into mature recipients Valuable cows that fail to conceive due to hormonal defects would not need to be culled
Limitations Expensive The technique for harvesting the ova is complicated Donors used repeatedly may become incapable of carrying to full term
FFA/SAE and Career opportunities Bred replacement heifer for the fair Embryologist Internship with veterinarian Veterinarian tech/ Veterinarian In-vitro fertilization at a Dairy Embryo transfer technician
What do you think has better pregnancy rates, embryos transferred that were frozen or fresh? Are there any limitations to using frozen embryos?