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Artificial
Insemination in the Boer Goat
Dr.
Stuart Southwell, B.V.Sc. - M.R.C.V.S.
Premier Genetics NZ. Ltd. - Drury, New Zealand
The
best way to spread elite genetic material throughout a population
is by artificial insemination (A.I.). Semen can be collected from
top sires, frozen, and then transported throughout the world, where
it can influence large populations.
The Boer goat industry is essentially in its infancy, but when top
sires are able to be identified, their genetics can be spread effectively
by artifical insemination. I believe the Boer goat industry will
use A.I. as a technique for spreading genetics more in the future,
where as it is now more dependent on embryo transfer.
SOME
IMPORTANT FACTS ABOUT A.I.
1. Obtain frozen
semen from a reputable source.
There is large variability in the number of live sperm obtained
upon thawing. Have your frozen semen checked.
2.
Rules Of Probablity
(a)
If using fresh semen, good results can be achieved with cervical
insemination. Best results are from natural heats, followed closely
by synchronized heats. What you should expect to achieve - 65%
pregnancy rate.
(b)
Frozen semen should only be used for laproscopic insemination.
Cervical inseminations are too variable. However, some operators
do achieve good results off natural heats. From a practical point
of view, if you are going to use frozen semen, then synchronize
your does and inseminate laproscopically. Anticipated pregnancy
rate - 60%.
3.
When To Inseminate
Approximately
12 hours after first sign of oestrous. If the does are in season
in the morning, inseminate in the evening. In season in the evening,
inseminate the following morning.
4.
Doe Management
Female
goats must be prepared carefully prior to insemination. Does must
be run together at least six months prior to programming. If they
have kids at foot, these must be weaned two months before insemination.
DO NOT mix groups of does just prior to programming, as it won't
work.
Two
weeks before the commencement of the programme, teaser bucks should
be run with the does. This will stimulate oestrous and hence begin
the reproductive mechanisms.
At
the onset of the program does need to be nutritionally "flushed".
This continues through to insemination and is maintained until
40 days past insemination. The doe will be gaining weight over
this period and will have greater pregnancy rates by doing this
than if she had not been flushed.
A TYPICAL A.I.
PROGRAMME WOULD BE AS FOLLOWS:
Day
1 - CIDR IN
Day 17 - CIDR OUT
Day 19 - HEATS
The
use of P.M.S.G. is debatable. Out of season situations do require
the use of P.M.S.G. Dose rates are 150 I.U. to 400 I.U. per goat.
This is normally given at CIDR OUT.
In
season situation - I don't recommend the use of P.M.S.G. as I feel
it reduces the pregnancy rate. Good management will give good results.
KEY
POINTS TO A SUCCESSFUL A.I. PROGRAMME
1.
Good Doe Management
2. Use of Quality Semen
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ABOUT THE
AUTHOR
Dr.
Stuart Southwell, B.V.Sc - M.R.C.V.S.
Premier Genetics N.Z. Ltd.
No one
individual has contributed more to the development of the
international Boer goat industry than Dr. Stuart Southwell
of Premier Genetics N. Z. Ltd in Drury, New Zealand. He is
widely known and respected for pioneering many of the embryo
transfer techniques and programme protocols that are being
employed by veterinarians and goat producers in many different
countries of the world, and has willingly shared his knowledge
and experience with those who have sought his advice and counsel.
In addition to sharing his surgical techniques with other
of his fellow veterinarians, Dr. Southwell has, himself, performed
embryo recovery, splitting, and transfer on many thousands
of Boer goats.
See also:
"Embryo Transfer In The Boer Goat".
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