Comparing Conventional Embryo Production and In Vitro Fertilization(IVF) as a Means to Propagate Superior Genetics in your Beef Herd Justin R. Kristjansson, DVM For almost 50 years beef producers in Canada have
and required time for the donor and recipient to heal
been utilizing embryo transfer technologies to multiply
along with an increased risk of post-operative
superior genetics within their herds, and their breeds.
complications.
With the importation and increase in popularity of the Continental beef breeds in the 1970s came a demand
Early surgical embryo recovery and transfer techniques
for the genetics that surpassed the availability of live
have since been replaced by non-surgical transcervical procedures now known as “conventional flushing”. In a conventional flush, the donor dam is subjected to a hormone synchronization protocol that results in her ovulating multiple oocytes (eggs) into her uterus that are then fertilized via artificial insemination. The donor dam incubates the developing embryos for seven days, and on day seven a catheter is placed into the uterus of the donor dam and the uterus flushed out with specialized fluid media that allows for the recovery and survival of the
cattle in Canada at the time. Veterinarians and
Conventional flush protocols result in an average of
researchers, in various places in the world including
seven, Grade 1 embryos per collection. The number of
MAINE MAIL | VOL. 10 ISSUE 1
embryos.
Canada, were developing protocols to produce multiple
embryos varies considerably based on each individual
embryos from elite females, to recover them intact from
donor dam’s response to the hormone treatment
the donor dam’s uterus, and transplant them individually
protocol, ranging from a low of 0 to highs in the 20s and
into the uterus of recipient dams.
30s.
Early techniques to recover embryos from the uterus of
In recent years In Vitro Fertilization (IVF) has arisen as
the donor dam and transplant to the uterus of a recipient
another means of embryo production from high genetic
dam involved surgical procedures for both cows. While
value females. In Vitro is Latin for in the glass, as every
embryo production rates, and subsequent pregnancy
step of embryo production after oocyte collection occurs
rates of transplanted embryos were generally quite
in a laboratory, not in the living animal (in vivo).
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required to perform the embryo recovery and transplant,
good, surgical procedures greatly increased the time The term IVF in the cattle world has evolved to
...cont’d
