Lodi Veterinary Care offers a wide array of
Advanced Reproductive services!

Conventional embryo flush:

Conventional embryo flushing is available on-farm and in-house here at the clinic.  In a conventional flush, hormones are used to encourage the donor to ovulate multiple oocytes (unfertilized eggs), as opposed to the typical one or two.  At standing estrus the donor is inseminated one to three times to fertilize as many of these eggs as possible.  About 7 days after estrus and insemination the embryos are “flushed” from the donor using specialized equipment and media developed to be embryo-friendly.

The average gain from a conventional dairy flush is 6 embryos (slightly higher in beef cattle), but the range is quite large—anywhere from 0 to upwards of 20 embryos may be collected in one flush.  The variance can be attributed to factors such as the donor’s energy balance, genetic predisposition, or a history of reproductive issues such as urine pooling and endometritis.  On the occasion that a conventional flush initially unsuccessful, there are many techniques that can be used to improve the outcome.

In-vitro Fertilization:

Oocytes (unfertilized embryos) are aspirated directly from the ovaries of live donors using a needle connected to a vacuum system.  The needle is held within a vaginal probe that is guided via ultrasound through the vaginal vault and into the ovary which is manipulated per rectum.  This process is called trans vaginal oocyte recovery (TVOR) or ovum pick up (OPU).  The oocytes are washed, graded and then placed into maturation media.  They are then fertilized, and cultured for 6 days.

What are the advantages of IVF over conventional flushing?

1. IVF can be used in senile, pre pubertal and even pregnant heifers and cows through the first trimester.  This allows for the collection of sick or injured aged or young valuable animals in the event that they are not able to reproduce conventionally.  Additionally, this technique allows for the collection of high-genomic cows that are already pregnant, but have demand for embryos or pregnancies. 
2. One straw of semen can be used to fertilize the ooctyes of 6 to 12 donors collected in the same day, or one straw of semen can be cut into thirds or quarters to be used in subsequent collections.  This allows for the use of one expensive straw of semen for many cows, or multiple collections.  
3. IVF is an option for cows that have poor conventional flush results.  By fertilizing and maturing the embryos in the lab, the cow’s only job is to provide the oocytes.  IVF eliminates many of the steps between insemination and flushing on the cow’s end, thus eliminating many reproductive issues contributing to poor conventional collections.

Embryo Transfer:

Embryo transfer involves planting embryos that are fresh from a flush, frozen, or matured in-vitro in a recipient who is either synchronized or naturally 7 days past standing heat.  

What are some of the benefits of embryo transfer?

-a more rapid rate of genetic improvement.  Less desirable heifers or cows can be used as recipients for high-quality embryos, therefore eliminating the undesired genetics and producing more desirable calf.

-genetic disbursement.  Embryos can be frozen and sold to other farms and even other countries, allowing for the proliferation of high-quality genetics as well as potential income.

-increased offspring from superior donors.  Donor flushing allows for the collection of multiple potential calves from a single estrous cycle, and can be used once every 30 to 60 days, rather than the production of one live calf per year.

-may help problem breeders.  By transferring an embryo that is already viable (has made it into the uterus, is fertilized, and is ~7 days old) you eliminate many of the steps that may be contributing to a cow’s inability to get pregnant.  Often transferring an embryo to problem breeders helps them breed back.

Donor Housing and Recipient Herd:

Lodi Veterinary Care offers excellent care to your donor in our donor herd.  Because Lodi is a full-service practice, not only can we offer you premium reproductive services, we also have a full staff of general practice DVMs and vet techs to best care for your donor.  If your donor is housed at Lodi, our doctors are able to monitor your donor more closely to determine the stage of their cycle.  This is especially beneficial for donors who have a history of flush problems, silent heats, or irregular cycling.  Our experienced herdsman can give shots at the correct timing interval so that you don’t need to be available every 12 hours, and to assure that they are given accurately to ensure maximum effect.

Lodi also offers a 100-head recipient herd comprised of beef cows and heifers, and dairy heifers.  Our herd is 100% biosecure, and all of our recipients must test negative for a wide array of diseases before they are allowed to enter the herd.  Our recips are also selected based on body size, demeanor, fertility, and mothering ability.