LLEP Stud Services
Natural mating Versus artificial insemination (AI)?
Artificial Insemination (AI) involves the collection, evaluation and
dilution of a stallions semen. A calculated dose of the semen can then
be chilled and transported to the mare. Once extended and chilled some
semen can be stored for 72 hours in specialised cool shipping containers,
making transport from places like Germany possible for some stallions.
However the majority if stallions semen will not last for more than
48 hours after collection, but not all stallions are the same and the
you can get the semen to the mare the better. Once the semen reaches
the mare she should be inseminated straight away as the semen lasts
longer inside the mare than in a container.
Due to the timing that is
it is critical to know exactly what stage of the cycle your mare
is at. This is where us vets come into play, and with the use of an ultrasound
machine we can quite accurately predict the time of ovulation and
instruct you when to order the semen form the stallion.
The advantagesof AI include:
- The desired stallion may be a great distance away saving time
and money travelling the mare back and forth.
- Greater effective use of the stallion- the collected semen can be
split into several doses meaning multiples mares can be bred from the
- When the semen is analysed its quality is also assessed, any stallions
with fertility problems are therefore identified and a different stallion
may be used instead.
- Reduced risk of injury to the mare from insertion of the stallion’s
penis or him biting her.
- Reduced risk to the handlers.
- Reduced risk of injury to the stallion from being kicked by a mare
potentially being put out of use.
- Mares would not need to visit the stud, therefore avoiding contact
between visiting mares and potential disease transmission.
- Insemination can be timed more easily as you don’t have to
wait for the stallion to have a time slot available.
- Frozen semen can be stored almost indefinitely in liquid nitrogen
- Greater control of disease as there is no physical contact between
the stallion and the mare. Eg. The Contagious Equine Metritis epidemic
in 1977 affected many Newmarket studs as they have natural matings.
The disadvantages of AI include:
- Chilled and frozen semen does not last as long as fresh semen
and therefore the insemination must be carefully timed. This requires
a high level of veterinary input and therefore expense.
- Pregnancy rates are generally lower with frozen semen than with
fresh or chilled semen. Frozen semen is therefore not advisable
for use on
older mares or those with suspect fertility.
- Semen can be diluted so one stallion could father thousands of
foals in a season, thus making hundreds of stallions redundant
and putting most studs out of business. There is also a genetic argument
against overuse of stallions.
- There is a slight risk that a mare may
unwittingly be inseminated with the wrong semen, therefore to ensure
that the mare was in
foal to the right stallion, all resulting foals would need to
be blood- typed.
- Foals by A. I. are prohibited in the Wetherby's studbook, i.e. cannot
be used in thoroughbreds for racing purposes.