The Original Glass Equine IUD ~ The Natural Choice
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"Glass Balls Mimic Embryonic Development" - Three equine specialist from the College of Veterinary Medicine at Auburn University are responsible for research presented in a paper at the 2001 American Association of Equine Practitioners meeting in San Diego*. Their research focused on the use of a glass ball inserted into the uterus of a mare in order to suppress estrus.

The following interview is an excerpt borrowed from dvmnewsmagazine.com* Apr 1, 2003 -
"The size of the ball is important, and a 35-mm diameter ball seems optimal. After adequate preparation, a sterile palpation sleeve is used and the glass ball is passed vaginally through the cervical lumen and into the uterine body. The glass ball can then be manipulated via rectal palpation and moved further into the uterine body.

Correct placement of the ball at the horn-body junction can be easily confirmed with an ultrasound examination. Some practitioners follow placement of the ball with infusion of antibiotic (ticarcillin at 1 gram is recommended by Nie) to help with any possible infection. Correct sterile technique will lessen the need for such use however.

The ball should be placed within 24 hours of ovulation. Some veterinarians have reported that certain mares will spontaneously expel the balls, but this is uncommon and was not observed in any of the mares in the university study. The use of glass balls to suppress estrus provides the practitioner with a safe, simple method of keeping some mares out of heat.

This method does not have any significant disadvantages for immediate performance use or for long-term reproductive use. It does not require extra-label drug use and it offers the owner a more "natural" means of controlling a potentially difficult mare. So before you lose your marbles dealing with that "witchy" sporthorse, consider putting one in." DVM Newsmagazine

UPDATE; It has been suggested that the ball be removed during winter months or between cycles.

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I have a mare that likes to act out when she is in season and I was wondering if there is anything I can give her to keep her from cycling?

ANSWER: by Dr. Brian Atwell, Maui Equine Veterinary Services;
There are a few products on the market today to help with this situation from hormone supplements to Euine IUDs. Some mare owners choose to put mares on either a daily oral progestin such as Regu-Mate or give intramuscular injections of progestins. These products do work but can be costly and occasionally difficult to work with. The oral progestin can be absorbed into the skin if spilled on the owner and the injections are oil based and occasionally cause muscle soreness.

Other products used to help settle down mares are available as well such as steriod injections every month, but long term steroid use does have its down side as well. One of the best ways to help deal with this issue is to implant an Equine IUD. This method involves the placement of a 35mm diameter sterile surgical pyrex glass ball into the uterus of a mare at the time of ovulation.

The use of the glass ball to suppress estrus cycles is a safe, simple method of 'tricking' the body into thinking there is a fetus present and keeping the mare out of heat. There are no significant disadvantages for performance or for long term reproductive soundness. It does not require any 'extra-label' drug use and is a more natural appoach that is effective in over 70% of mares.

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Mimic embryonic development
Maui Equine Vet Service

*I have tried to hold my pricing the same for almost 20 years now. But unfortunately my cost for supplies has more than doubled in that time. I have now had to increase pricing for all items. But if you order a dozen or more you will save 20% now which is a savings over the old prices. And since I am not a high volume business I still must charge for postage which increases every 6 months. I hope you understand and continue doing business with us for a quality product.
I am solely responsible for any editorial errors. There are no veterinary doctors associated with this site. Glass Bay Studio/glassmarble.com is only the manufacturer and has no educational/formal training in equine veterinary practices. Please refer all questions to qualified personnel.

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Last updated March 25, 2020
The name "Marebles" and the "Marbles"Logo cannot be used without express written permission. copyright - 2001/2021
Dr Gary Nie's name used with written permission - 02/06 and is not associated with this site or glass bay studio at glassmarble.com.
Dr Brian Atwell's Q&A used with verble permission 08/09.