"Question: I have a mare who is typically difficult
to train this time of year due to "exaggerated" spring estrus symptoms. My
vet has suggested, as an alternative to Regumate, the insertion of a sterilized
marble into her uterus. He says there has been significant discussion of
this and it is proving useful. I am concerned about risking her future fertility
as I may want to breed her in a few years. Plus, this just sounds plain bizarre
to me but I trust my vet. Any thoughts on this procedure regarding efficacy
and long term fertility repercussions would certainly be appreciated?"
"Answer: This technique was described at the national AAEP (equine practitioner)
meeting about two years ago. You induce heat or wait on a heat cycle. When
the cervix opens, then you induce ovulation with HCG or Ovuplant. After you
prep the mares vulva, you then insert a sterile marble that is 30 mm in diameter.
This simulates a conceptus for the mare. I may be mistaken but originally
the researchers removed the marbles after 60-90 days with no effect on future
fertility. I work in an equine-only referral practice in Lexington, KY where
future fertility is ALWAYS the PRIMARY concern. I have personally put marbles
in mares and taken them out 5-6 months later and had them conceive on the
next cycle. The marble is non-irritating, if done correctly, is sterile,
and far safer for the future of the mare than progesterone implants (used
in feedlot cattle). Besides the fact that Regumate is messy, expensive, has
to be given every day, and is not a good idea for a human female to handle
since it absorbs through the skin. As a side note, it is a very common practice
to breed racing mares, get them pregnant and continue to train them for racing
for 3-5 months after they conceive...but in answer to your question, the
marble idea was adequately researched and a common practice in many reproductive
practices."
Further Comments:
"NOW, I've also heard of people who had this done and it had no affect whatsoever
on the mare. They still had PMS, otherwise know as Pissy Mare Syndrome."
"We have three mare's that we haul. When one start's PMS, the other's will
within a few day's! At least you get it over with at the same time. It doesn't
bother their performance, but that squatting, winking and hollering, when
away from home, does get old. But, we just put on our big panties and deal
with it."