The Rural Voice, 1981-01, Page 7known, but is exceedingly difficult. The
male cat ejaculates less that 1 cc. of
semen and this is difficult to collect.
EXOTIC ANIMALS
The techniques of artificial insemin-
ation are now being utilized by zoos
around the world to breed rare varieties
of animals which are becoming extinct.
TIME magazine (Nov. 10, 1980) reported
that the Bronx Zoo has successfully bred
Przewalski's horses, a wild species now
believed to be extinct in its native
Mongolia; Pere David's deer, which
vanished from China around the turn of
the century; and the European bison,
only recently reintroduced into Poland,
where the last wild one was killed in 1921.
Last summer at the London Zoo a baby
puma, named Bonny, was born via
artificial insemination to a mother rend-
ered receptive by hormone injections.
TIME went on to tell about one of the
bravest uses of A.I. involving the Bronx
Zoo's herd of gaur, large wild cattle from
southern Asia. By treating a female with
hormones, zookeepers got her to produce
more than her usual number of eggs.
After fertilization the embryos were
removed and implanted in domestic
cows, which are now acting as surrogate
mothers. If the experiment works, it will
be the first time different species have
been successfully transplanted into do-
mestic cattle.
Artificial insemination is definitely
here to stay, thanks to the many
dedicated people who have developed the
techniques now used routinely in cattle,
poultry and swine and to some extent
with horses, goats, bees and even
humans.
Inherited characteristics behave ac-
cording to definite scientific patterns.
And genetics is the science that deals
with these patterns and inheritance in
general.
The study of genetics has already led to
improved production of meat and milk.
and to the survival of endangered species
of animals. Who knows where the science
of genetics will lead to in the future?
Embryo transplants: both sides of the story
BY SHEILA GUNBY
"The development of embryo
transplants may revolutionize the cattle
business allowing high quality cows to
produce large numbers of offspring."
Sounds good.
O.K. Let's back up a bit.
T6e average cow normally produces
three to four offspring in her lifetime, but
by using embryo transplants, this can rise
to nearly 50 offspring per cow, according
to the.Ontario Veterinary Association.
Hormones are given to an outstanding
cow, causing a large number of ovarian
follicles to grow and ovulate all at one
time. The cow is then bred 6-30 hours
after ovulation. About a week after
breeding. the fertilized embryos will be
removed from the cow by tlushing the
uterus with large amounts of fluid.
If ten embryos are recovered from one
donor cow, then ten recipient cattle of low
or average quality will be required. each
receiving a single embryo by surgical or
non-surgical transfer. Thus, 10 calves
from one "super cow."
EMBRYO TRANSPLANTS
Scott Stewart, VIA PAX, Woodbridge,
one of the better known firms dealing in
embryo transplants,does a lot of work for
breeders in southern Ontario, Quebec,
New Brunswick and Manitoba. They also
sell embryos - fresh or frozen -on the
international market.
Speaking about the actual embryo
transplant, Scott says there is some stress
and there could be a slight drop in milk
production. The pregnancy rate is around
60-65 per cent whether the transplant is
done surgically or non -surgically and
both methods are used equally. If the
heifer is large. then it is usually done with
a catheter inserted through the cervix. A
surgical transplant is accomplished via a
small incision in the kidney region or high
flank, revealing the uterus, so the embryo
can be placed inside.
SEXING OF EMBRYOS
At the experimental stage is the sexing
of embryos. In the "News Bulletin",
published by the University of Guelph,
Dr. Liz Singh of Agriculture Canada
explained the method in the sexing of
embryos:
"Scientists remove one cell from the
embryo at the five day stage of a nine
month gestation - the embryo at this
stage has between 32-64 cells. The
peeled cell, placed in a tissue culture,
begins to divide and sometime within a
24 hour period, reaches a stage where
researchers can identify the chromo-
somes and subsequently the . sex of the
animal; however, research is still in the
early stages. Although the process could
be speeded up by the removal of more
cells from the embryo, this usually results
in genetic abnormalities in the
offspring."
ECONOMICALLY SPEAKING
Well, embryo transplants are not for
everyone. It all costs money. Stewart
says only about 2 per cent of all Holsteins
in Canada could justify using this
method.
An on-farm embryo transplant works
out initially to`around S300. Broken down,
that is $100 for drugs and $200 for
flushing. Four hundred dollars is charged
for each confirmed pregnancy.
SUCCESS:
Let's go to a man with successful
results with embryo transplants, Court
Carmichael, R.R. 3, Ilderton. From 38
embryo calves, he has had 19 heifers and
19 bulls - a fifty/fifty split '- from five
cows. Thirty-three of the calves were
from three cows.
Carmichael says the key is having a
proven brood cow as the donor mother.
"Assuming the people in the business
are honest," he says, "they all do a good
job technically, and get a good flush. The
first two flushes I did on one cow resulted
in absolutely nothing. But the next flush
resulted in nine pregnancies. It all
depends on the donor mother, she has to
be proven. That's the key."
IN THEORY, IT'S A GOOD IDEA
After being involved in embryo trans-
plant for three years, Robert Vodden,
R.R. 1, Clinton has another story.
"In theory, it's a good idea," he says,
"but in our case, we've averaged one
pregnancy per cow. From eleven flushes,
we got 12 pregnancies. Then, out of eight
calves, so far only one was a heifer.
"It takes a pretty exceptional cow - one
that you can move a bull from. Our last
cow was an exceptional cow - she had lots
of eggs. Flushed her three times - 10 eggs
the first time, 17 the second, but only
two pregnancies. Then none the third
time, like she was used up.
"Guess there's a place for it out on a
large scale -no."
FROM BOTH SIDES OF THE FENCE
OMAF Dairy Specialist, Dennis
Martin, of the Clinton Office, says ET
work has created a lot of excitement with
breeders across the country.
"It's nice and rosy from the surface,"
he says, "but it's a complicated and
costly procedure. At first, you say, gosh,
it's.great. You take that cow and get half
a dozen heifers - your're off to the races -
but there's a little bit of luck in there.
"Different producers could each tell
you a different story. When people talk to
me, I direct them to people on both sides
of the fence. I tell them to talk to both
sides before they make any decisions."
THE RURAL VOICE/JANUARY 1981 PG. 7