AI is the practice of inseminating a mare without natural covering. The semen is collected from the stallion, filtered,
diluted and either frozen in liquid nitrogen, chilled to 4c in a special container or kept at body temperature and used immediately.
Advantages:
Safety.
When covering, the risks of kicks and falls are always present.
Infection Control. Because
no covering takes place stallions cannot become infected by venereal diseases. It is necessary to recieve proof of freedom
from disease when selecting stallions especially those from abroad.
Wider Stallion selection.
Stallions from further afield and abroard can be used. The use of frozen semen allows semen from horses anywhere in the world
to be used.
Convenience. The use of chilled semen allows insemination to be carried out
at your yard. This is not yet really possible with frozen semen.
Assessment of fertility. Microscopic
examination of the semen gives an idea of the sperm viability before insemination.
Sub-fertile mares.
Mares with endometritis problems are always best to be inseminated to reduce post-covering inflammation and the level of contamination.
Disadvantages:
Expense.
Generally the increased veterinary input and stud effort comes at a cost. This is dependant on the type of semen
used.
Untested semen and the spread of EVA. Semen from untested horses from Europe should
not be used. This especially applies to competing horses that go from country to country then are collected from without additional
testing.
Fertility: The pregnancy rates associated with AI are comparable if not better
than that of natural covering. This is very stallion dependant; some stallions semen does not freeze well, others do not cope
well with extending and chilling.
Insemination with Frozen semen
Insemination must be done within
4-6 hours of ovulation. For this reason the mare must be checked 6 hourly over the critical ovulation period. We do everything
in our powers to keep this as simple as possible at the same time maximising the chance of pregnancy.
The semen
has to be stored in liquid nitrogen and requires equipment and manpower for the process of thawing and insemination. This
means that we do need to have mares at the practise.
Preparation.
Covering history. A
full record of previous coverings, pregnancies and foalings is important as well as all veterinary fertility exam results.
Agood
record of seasonal behaviour is extremely useful. The most common reason for failure of mares to come into season after injection
is if this is done in the wrong part of the cycle.
An all round examination needs to take place to make sure the
mare is able to breed. Obesity, poor condition, vulval tears and poor vulval confirmation, Cushings disease and other chronic
diseases are all associated with reduced fertility.
Internal Examination usually together with ultrasound HELPS
to get an idea of where she is in the reproductive cycle. The overies, uterus and cervix can all be examined to assess fertility
and stage.
Swabs: Venereal diseases are routinely checked for by clitoral swabs, these take at least 6 days for
results.
Mares with any history of conception failure have an endometrial swab where a swab is taken from the lining
of the uterus and smeared on a slide. This allows the assessment of the level of inflammation and infection present.
Process
of Insemination... semen must be recieved from stud/storage before the cycle is started.
1) Bringing the
mare into season. If a corpus luteum is present with a 'dioestrus' uterus a single injection of prostaglandin(PG)
will bring the mare into season. For timing this is done on a friday.
2)Monitoring.The mare is brought into the
surgery on the Tuesday. From this point she is examined twice a day until a follicle of >30mm is present and the uterus
oedema is maximal.
3)An ovuplant implant is inserted at midnight and the mare examined twice the next day then from
6.00am the next day she is examined at 4-6 hour intervals until ovulation. A full insemination dose is inserted before and
after ovulation if ther is enough, if not it is given after ovulation.
4)The next daythe mare is washed out and
if necessary the vulva caslicked (sewn up).
Pregnancy diagnosis. This can normally be done from 12 days post service
by scan but detection of twins normally necessitates at least 2 examinations, one at 16/18 days and another 25/35 days. After
45 days fetal loss is rare so a further check after this date is extremely useful. Without these checks we cannot guarantee
to pick up every twin.
In Short:
Preservice checks & swabs
Friday:
Inject PG
Tuesday: Scan..... If foll>30mm then hCG or Ovuplant
Next
day: Inseminate
Next day: Post service check
Then: 16 day,
28 day, 45 day, scans for pregnancy.
cost:
Artificial Insemination Package
Chilled semen: £200 + vat per cycle (plus keep & foal fee after the 3rd day).
Frozen semen: £260 +
vat per cycle (plus keep & foal fee after the 4th day).
The above prices are only for the veterinary work carried
out at the Isle Veterinary Group premises.
price includes: All ultrasound examinations,
Endometrial swabs.
Insemination.
Assessment of semen motility.
Ultrasound
pregnancy examination at 15/16 days.(if carried out at clients premises visit charges will be incurred).
A single post-ovulation uterine treatment if required.
All drugs to ensure insemination are performed at optimum time.
All other costs are not included in the package price.
In foal fee: An additional one-off fee
of £100+vat will be charged if the mare scans in foal.
If your mare is not in foal, you will not be charged the foal fee.
Keep fees: £9.40
per day grass keep.
£10 per day stabled.
£2 extra per day for mare with foal at foot, stabled or at grass.
The above keep fees will apply from the day your
mare arrives with us through until her day of departure.
TERMS AND CONDITIONS:
In foal fee: This fee applies to all mares. All mares will be presumed to be in foal when leaving the practice. If
the mare is confirmed by us or a vet's certificate not to be in foal before 1st Octobert the foal fee will be credited
to your account.
Veterinary
Treatment The Isle Veterinary group reserve the right to provide for the mare and foal any welfare or emergency treatment
deemed necessary.
Insurance. All animals are at their own risk for the duration of their stay with us and whilst every care will be takn
during their stay The Isle Veterinary group do not accept liability for injury or damage to any animal. It is the responsibility
of the owner to ensure adequate cover.
Invoices. The package fees are payable on arrival of the mare. All other fees and livery charges are payable separately
on collection of the mare.
All mares are inseminated at the owner's risk The Isle Veterinary group do not accept
any liability for injury or damage however caused.
All semen stored by The Isle Veterinary group is done so at the owners
risk and no liability is accepted for loss or damage. All semen deliveries to The Isle Veterinary group remain the responsibility
of the owner at all times.
If your mare has not fallen pregnant to the same stallion after 3 attempts it is extremely
unlikely to happen with that stallion. It may be worth reconsidering the individual stallion or the method of insemination.
Results:
Generally
frozen and chilled have very simular results depending on the fertility of the stallion with that method of insemination.
Conception
rates are in the order of 50/65% to each insemination.
Annual pregnancy rates are around 75/90%.
These
rates vary between each year and stallion.
