WELCOMED on stage by MC Brendan McArdle, veterinary sugeon Larry Dunne was described as straight-talking and extremely knowledge in the area of equine reproduction.

Dunne joined the conference to share his expertise in the embryo transfer process and left the audience with plenty of food for thought, demonstrated by the large queue of people waiting to speak to the Wicklow man after his presentation.

A question from the floor sparked Dunne to call for regulation on semen from stallions who have received medication for their joints or back, saying it causes fertility issues.

“In my opinion, semen should have a cert with it to state if that horse received joint or back medication in the last 12 months.

“People are paying €800 or €900 for semen and not getting a pregnancy. We are entitled to that information. We are spending a lot of money and someone has to regulate it.”

He added that competing mares who have the same medication are also more difficult to get in foal.

NUTRITION

Discussing feeding during pregnancy, Dunne suggested introducing seaweed into the diet three months prior to the breeding season, saying mares who are feed seaweed consistently before insemination will give different results.

Many horse feeds contain magnesium sulfate as a calming factor, but Dunne is of the opinion that it is blocking the uptake of iodine, which is vital for the reproductive system to function correctly.

As is the case in cattle, Dunne said: “The iodine in the seaweed seems to be able to overcome the blockage factor of the magnesium sulfate. It is only an opinion but I am yet to have someone to prove my opinion wrong.”

In terms of using Regumate to keep your mare in foal, Dunne added: “You must go with a large quantity otherwise you are wasting your time and it has to go for 120 days.”

He did however remind the audience that just because your mare loses one pregnancy, it does not mean there is something wrong. “Ten percent of mares will lose a pregnancy, not because there is something wrong, but because the embryo will have some defect around 30 days. It’s only if you’ve lost your second pregnancy, then go on Regumate.”

EMBRYO TRANSFER

Dunne outlined some of the key facts he suggests make for successful breeding, defining success as having a 70% pregnancy rate from natural cover, fresh, chilled or frozen semen.

Process

  • The egg is released and fertilised up the fallopian tube resulting in an embryo. Six days later the egg moves into the uterus where it can either establish a pregnancy or be flushed for embryo transfer.
  • For the transfer process, the egg is removed at seven days from the original donor mare and transferred to the recipient mare.
  • Transfer can occur fresh within three hours or can be frozen and then transferred to recipient at a later date.
  • Flushing the donor mare to remove the embryo that has originated from frozen semen will be done 12-24 hours behind fresh semen. The mare should be prepared with sedation, an empty bladder and clean vulva, a Foley catheter will then be placed into the uterus.
  • One litre of flush medium will be massaged throughout the horns and body of uterus.
  • The flush is then brought through an embryo filter where the embryo is examined under microscope.
  • 90% of embryos will appear in first flush with a negative result being declared after three refreshes and no detection.
  • The embryo is washed and transferred to straw for implantation or alternatively frozen.

    • Benefits

  • Possible to obtain more than one pregnancy in a season, can be repeated every 21 days.
  • Suitable for mares competing or a mare intended for sale.
  • Suitable for a mare who cannot carry full term pregnancy.