I have a mare who I have bred during four seasons -- only once resulting in a foal. The first two seasons she was covered AI with the same stallion (different vet). Everytime she was covered during the second season her uterus filled will fluid. The third season we used a different stallion (still AI) and she took immediately, no fluid in the uterus, and we have a lovey filly as a result. This year, we tried a third stallion (AI) and again, first cover of the year, she has a uterus full of fluid. The vet says it is a reaction to the semen -- but this is my question -- is it the semen, the extender or both? Does anyone know more about this and can you offer me insight. If it is a reaction to the semen and not the extender, is there a way to tell (blood type?) which stallions will do this before we choose and sign a contract. Thanks!
Posted on Monday, April 28, 2003 - 10:36 pm:
ALL mares develop uterine fluid post-breeding. It's a part of the natural post-breeding inflammatory response. Without that response bred mares would repeatedly become infected. Most mares however clear it in the 24-36 hours after breeding.
This inflammatory response is initiated by the sperm, and moderated by seminal plasma.
Why your mare would react differently between stallions is puzzling. It does however sound as though she is a "delayed uterine clearance" mare, and would benefit from use of oxytocin post- (and possibly pre-) breeding to clear fluid. "Click" here for more information on that.
It is a possibility that the time she got pregnant there was a lower volume of inseminate (reducing inflammatory response), or perhaps on the other occasions her uterus was in a previously induced inflammatory state, but not that one. To try and guess why she achieved pregnancy on the one occasion, but not the others would be pure conjecture and not particularly helpful as it may be incorrect.
The concept of a "reaction to the extender" is in the realms of Internet fantasy, and is in fact listed in my "breeding mythinformation" article to be seen here. There may however be a reaction to antibiotics in the extender - is the mare penicillin sensitive, and were there penicillin-family antibiotics used in the extenders to which she reacted?
Assuming there is not a history of penicillin sensitivity, I would manage this mare with oxytocin in the manner outlined in the article above, and if necessary on a subsequent cycle use a post-breeding uterine lavage.
Posted on Tuesday, April 29, 2003 - 10:39 am:
Thank you very much for the helpful information. The mare had not cleared the fluid within 36 hours and the vet followed the protocol listed in your "click here" article. I am relieved to know there is no such thing as an extender allergy and it is particularly helpful to understand what the vet meant by "reacted" to the semen. Because she has no previous history of antibiotic sensitivity, I am assuming that she experiences delayed uterine clearance. I was told that the stallion (this year) has very highly concentrated semen. Based on the information you provided above, I wonder if that contributed to the significant fluid reaction in this case. I know very little about how semen is prepared for shippment -- so perhaps this is a stupid question -- but would it help if the stallion manager prepared and shipped a less concentrated dose for this particular mare? Of course, I am assuming that she is not pregnant -- and I may get lucky that the post-ovulation treatment of the uterus was sufficient -- but in the event it was not, I am trying to prepare so as to make the best of the next cycle. Thanks again for your time and helpful information.
Please note that opinions, product information, advice or suggestions posted on this bulletin board are not necessarily those of the management at Equine-Reproduction.com nor does the maintenance of the post position indicate an implicit or any endorsement of that information, opinion or product.
Further, although we have the greatest respect for the posters offering assistance here, you are advised to seek a consultation with your veterinarian prior to using information obtained from this board if it is of a veterinary nature.Proud to be sponsored and supported by: