advice giving Regumate to pregnant mare

[Krose]

Last year I bred my mare and she had ovulated sometime during the night before she was bred in the morning. Because of that, thinking she may not take and we’d be breeding again, I started Regumate on day 5. She was getting 12ccs since she is a big mare. This was her first breeding ever.

On day 17 she was pregnant and we had a progesterone test done. That took a few days before results were back, which was that she was producing on her own. So I then weaned her off the Regumate by giving 10cc, then 8cc, 6cc and so on. That probably started around day 20 or 21, and took a week or so. I didn’t take good notes unfortunately if I did 2 days at each of the reduced amounts (i.e 2 days at 10cc, 2 days at 8cc) or just one day. So that may have taken me to somewhere around day 26 or maybe closer to day 30.

At day 35 she was still pregnant. At day 57 she was not.

I know with an ovulation before breeding that increases risk of EED. But I thought if still pregnant at day 35 that would not be related.

I’m breeding my mare again this year; she was literally bred this morning. She took so well last year, which we thought was going to be the hard part, we decided to try again.

My vet, who admits the science behind giving Regumate to maintain pregnancy isn’t that strong, suggests doing it in these situations when there isn’t another obvious reason as to why she aborted/expelled/whatever the right terminology is.

And I should note my mare is 16 and a maiden. Because she is healthy, fit, cultured clean, etc we decided to try again this year. In case anyone’s advice would change based on that knowledge.

Anyone have any advice or suggestions?

[Katona]

Lot’s of good information here: http://www.equine-reproduction.com/articles/Regumate.shtml

My vet says if uterine tone and progesterone levels are good, there’s not really reason to use it…

[gumtree]

The term at that stage is refereed to as “absorbed”. In the TB breeding world we check for preg at 15 days. If everything looks text book check again at 30. Or at 20 if there is something “suspicious”, possible twin etc. We check again at 45. This is all done by ultrasound. Most TB mares will absorb between 15 and 30 some between 30 and 45. Most TB breeder just one last time at 60 days depending on the time of the breeding season. Most generally don’t cover in late June. Leave the mare open to get an early jump next season.

We take the time and money because the in the TB world we want the mares in foal or back in foal ASAP. So if they come up empty we can short cycle and breed again asap.

As to the best day to breed is made much easier once we have a “handle” on the mare based on previous breeding’s. Maidens can be tricky. We US based on how they are teasing. You can usualy use a gelding for this. On average we breed when the follicle is approaching 45 and on “look, tone”. Some mares just under and others we’ll take a chance let her go one more day. Some it is better to let them go just over the top of text book. It’s a learning curve.

We pretty much always US the mare on the day she is going to be covered, bred. And hopefully teases real “hot”. The hot ones will start squatting, get slutty before they get near the teaser. Their urine is on the opaque side of things. I have never had a mare that exhibited this kind of behavior not get in foal and stay in foal.

Generally in the TB breeding world if we feel the mare should, needs to be on Regumate she stays on Regumate for months.

[Krose]

@gumtree

The term at that stage is refereed to as “absorbed”. In the TB breeding world we check for preg at 15 days. If everything looks text book check again at 30. Or at 20 if there is something “suspicious”, possible twin etc. We check again at 45. This is all done by ultrasound. Most TB mares will absorb between 15 and 30 some between 30 and 45. Most TB breeder just one last time at 60 days depending on the time of the breeding season. Most generally don’t cover in late June. Leave the mare open to get an early jump next season.

We take the time and money because the in the TB world we want the mares in foal or back in foal ASAP. So if they come up empty we can short cycle and breed again asap.

As to the best day to breed is made much easier once we have a “handle” on the mare based on previous breeding’s. Maidens can be tricky. We US based on how they are teasing. You can usualy use a gelding for this. On average we breed when the follicle is approaching 45 and on “look, tone”. Some mares just under and others we’ll take a chance let her go one more day. Some it is better to let them go just over the top of text book. It’s a learning curve.

We pretty much always US the mare on the day she is going to be covered, bred. And hopefully teases real “hot”. The hot ones will start squatting, get slutty before they get near the teaser. Their urine is on the opaque side of things. I have never had a mare that exhibited this kind of behavior not get in foal and stay in foal.

Generally in the TB breeding world if we feel the mare should, needs to be on Regumate she stays on Regumate for months.

Thanks…I know in the TB world they often keep the mares on Regumate, given the expense to get to that point, but I know there is alot of discussion regarding the overuse of Regumate. Hence why I wanted some feedback on what people have experienced. Even if not scientifically proven!

And ironically I thought reabsorbed was the correct term, but I was told after day 20 or so that was not technically correct! thanks.

[bugsynskeeter]

Did the embryo have a heartbeat at day 35? Did everything else look normal?

We always kept them on Regumate until at least the heartbeat ultrasound and then tested them for progesterone.

[Krose]

@bugsynskeeter

Did the embryo have a heartbeat at day 35? Did everything else look normal?

We always kept them on Regumate until at least the heartbeat ultrasound and then tested them for progesterone.

I don’t know actually. I didn’t ask, and I know the vet didn’t comment specifically on that…just that all looked normal, and the size of the embryo looked normal for around a 30 day old embryo. I will ask this go around, if it turns out she is pregnant when she is checked in a couple weeks.

My main concern is if other people have had experience where testing showed the mare was producing on her own, Regumate stopped, and then an issue like I had. Conservatively, after my experience last year, I’d prone to just keep her on it at least until 150 days, but I guess I’ve been influenced somewhat by all the negativity around the use of it and that if the mare tests ok, she doesn’t need it. And I guess those people would say she lost it between that day 35 and 57 for other reasons. It’s just coincidental that it was after she was weaned off the Regumate.

[bugsynskeeter]

We never tested that early - we tested our mares when a heart beat was detected. I’ve never stopped Regumate so soon.

[kathy_s]

We finally got our maiden mare settled this year using regumate. We had been trying for almost 2 years and though there was nothing physically wrong with her, we just couldn’t get her in foal. I consulted with the manager of the farm where the stallion stands and use her method for this type of situation.
Here were her instructions:
10cc of regumate once per day for 15 days
Administer lydolyse (spelling ?) on day 15
We checked her on day 7 and bred her on day 8 (post lydolyse sp? sorry)

“You breed her - when she ovulates give her a post breeding antibiotic treatment - start 10cc Regumate on day 4 post ovulation - keep her on it until you ultrasound her day 16 for pregnancy - if she is in foal keep her on it until she is at least 100 days in foal.” A. Alvarez

My mare just checked 60 days safely in foal and before we take her off the regumate on day 100, will have her progesterone levels tested.

I hope your mare gets in foal

[ASBJumper]

I think you may have simply weaned her off the Reg a bit early… but you definitely don’t need it past 120 days or so - that’s when the placenta starts producing progesterone and the pregnancy becomes “self-sustaining”, so to speak. At that point, even if your mare is producing literally zero ngs/ml of progesterone, the pregnancy should still be fine.

I had a true “low pg” mare - at 18 days in foal the test came back reading “0.2” (ngs per ml). She stayed on Regumate til the 4-month mark and then I weaned her off it over a period of a week. She delivered a very healthy colt the next year.

I think you’d be best served to keep your mare on Regumate til the 35-day heartbeat check, THEN do a blood assay to check her pg levels.

Good luck!

[Krose]

@ASBJumper

I think you may have simply weaned her off the Reg a bit early… but you definitely don’t need it past 120 days or so - that’s when the placenta starts producing progesterone and the pregnancy becomes “self-sustaining”, so to speak. At that point, even if your mare is producing literally zero ngs/ml of progesterone, the pregnancy should still be fine.

I had a true “low pg” mare - at 18 days in foal the test came back reading “0.2” (ngs per ml). She stayed on Regumate til the 4-month mark and then I weaned her off it over a period of a week. She delivered a very healthy colt the next year.

I think you’d be best served to keep your mare on Regumate til the 35-day heartbeat check, THEN do a blood assay to check her pg levels.

Good luck!

Thanks…at this point, if she is pregnant, which I won’t know yet till the 12th, I think I’m going to keep her on it beyond even the 30 day check, or 60 day check. Just to be on the safe side.

And I chuckle because for the people that have said keep her on it until xxx… it’s been 100 days, 120 days, 150 days, etc! There doesn’t seem to be agreement on even the time when the foal is producing itself! But I wanted the advice, so I’m glad for it.

[bornfreenowexpensive]

For a 16 year old maiden…I’d probably keep her on it. Looks like I will have two broodmares on it this year and one not. If they have trouble staying in foal or other issues…or as in your case, are an older maiden…I don’t think it is a bad idea and in the end…a drop in the bucket of the expenses you will have! Get a regumate dosing gune if you do not have one…they are worth it IMO.

https://www.valleyvet.com/ct_detail.html?pgguid=1e7ef63f-40dd-42b1-9b38-307237a4cc62

[Krose]

@bornfreenowexpensive

For a 16 year old maiden…I’d probably keep her on it. Looks like I will have two broodmares on it this year and one not. If they have trouble staying in foal or other issues…or as in your case, are an older maiden…I don’t think it is a bad idea and in the end…a drop in the bucket of the expenses you will have! Get a regumate dosing gune if you do not have one…they are worth it IMO.

https://www.valleyvet.com/ct_detail.html?pgguid=1e7ef63f-40dd-42b1-9b38-307237a4cc62

I’m almost positive I’m going to keep her on it, if she turns out to be pregnant. I only wish I had done the same last year…especially if it turns out she’s not pregnant this year.

And I’m not going to try again this year likely, with as late as it is now in the year, and next year she’ll be 17 and I’m not going to risk it at that point.

[Virginia_Horse_Mom]

Just had a 29 day ultrasound on my 17 yr old mare. She’s not a maiden though… Had two foals already. But had a 2a uterine biopsy 2 yrs ago. I got conflicting advice on regumate for her from 2 different vets at the practice. Her progesterone levels came back high, and her uterine tone is good, and we saw what we think was a heartbeat today. One vet… Our primary repro one… Said not to bother with regumate for this mare at this time. She thinks we are in good shape. A different vet who had been out earlier suggested starting it sometime around 30 days and keeping her on it until 100 days. She mentioned that progesterone can fall off quickly, and if the placenta hasn’t established enough in a uterus that’s a little challenging (2a), that’s when you can lose a pregnancy.

I’m going with the advice of our primary vet. But was curious if the other vet’s advice rang true… Or seemed off? I also now have a bottle of it on hand that I am not planning on using this season… How long is it good for?

[Krose]

@Virginia Horse Mom

Just had a 29 day ultrasound on my 17 yr old mare. She’s not a maiden though… Had two foals already. But had a 2a uterine biopsy 2 yrs ago. I got conflicting advice on regumate for her from 2 different vets at the practice. Her progesterone levels came back high, and her uterine tone is good, and we saw what we think was a heartbeat today. One vet… Our primary repro one… Said not to bother with regumate for this mare at this time. She thinks we are in good shape. A different vet who had been out earlier suggested starting it sometime around 30 days and keeping her on it until 100 days. She mentioned that progesterone can fall off quickly, and if the placenta hasn’t established enough in a uterus that’s a little challenging (2a), that’s when you can lose a pregnancy.

I’m going with the advice of our primary vet. But was curious if the other vet’s advice rang true… Or seemed off? I also now have a bottle of it on hand that I am not planning on using this season… How long is it good for?

I believing in listening to your vet, but I opened this thread to see what other people thought, as I started hearing bits and pieces here and there about keeping mares on Regumate, and what alot of TB breeders do, etc. Although there is alot of feedback about the overuse of it, being a hormone, etc. And the one of the first responders here to my thread noted as much…use if needed.

But just like you have heard in terms of it falling off, at that point it often is too late. Which is why I’m going to keep my mare on it until at least 5 months, short of a vet telling me it will be actually harmful to do so. I don’t want to experience what I did last year. Too much money and effort involved at this point if she is in fact pregnant this year.

And on the expiration…my bottles have always noted an expiration date. And last year I sold the rest of mine to a couple people who have mares they compete and use it during show season.

[RyTimMick]

There is different reasons you keep a mare on Regumate. Low progesterone is only one of them. Older mares, mares with poor conformation inside, Mares with bad tone, or loose cervixes. The fact is, if you are going to put a mare on regumate, you do it on day 5 or 6, not day 30(unless you want to test first, then supplement). You keep a mare on Regumate for low progesterone until day 120(145 days is to be safe), and then slowly ween her off about 2 cc’s a day after that. Older mares or mares with poor conformation, up until 30 days till the due date. The only true way to know about the progesterone is to pull multiple samples during the day, because it fluctuates. Around day 30 the ovaries will produce more CL’s which is the primary source of progesterone until about day 120 when you get it from the placenta. If your mare has fluid, or edema, or poor conformation, you need the Regumate regardless of progesterone levels.

[Krose]

@RyTimMick

There is different reasons you keep a mare on Regumate. Low progesterone is only one of them. Older mares, mares with poor conformation inside, Mares with bad tone, or loose cervixes. The fact is, if you are going to put a mare on regumate, you do it on day 5 or 6, not day 30(unless you want to test first, then supplement). You keep a mare on Regumate for low progesterone until day 120(145 days is to be safe), and then slowly ween her off about 2 cc’s a day after that. Older mares or mares with poor conformation, up until 30 days till the due date. The only true way to know about the progesterone is to pull multiple samples during the day, because it fluctuates. Around day 30 the ovaries will produce more CL’s which is the primary source of progesterone until about day 120 when you get it from the placenta. If your mare has fluid, or edema, or poor conformation, you need the Regumate regardless of progesterone levels.

Outside of my mare being older, everything else was in order last year, hence why she was weaned off. No conformation issues, no fluid during breeding, etc. But I appreciate knowing that if I keep her on it, for no other reason than she’s older, I don’t have to feel guilty about being part of people who “overuse hormones”! And both last year and this year we did start her on day 5. She has her first check tomorrow, day 17. Last year she was weaned off of it between day 20 and 30. But God willing she is pregnant tomorrow…she will stay on it. Either to 150 days or to 30 days out.

[CastleTop]

This has been a fascinating thread for me to read and I would love to know if your mare is indeed still pregnant and if you are still keeping her on Regumate. I bought back a mare that I am the original breeder of this past year bc I value her bloodline and want it in my breeding herd. She is 14, had 1 previous foal 3 years ago, and had been a showjumper with a career of her own. I was told she was out on a broodmare lease but did not conceive. The next year the owner tried breeding her once but it did not take and then she went on market. This past year, honestly trying to get this mare cycling regularly and to conceive has been the most difficult endeavor of my 32 years as a breeder! Part was her- hemorrhagic follicle, irregular cycle and always a bit of fluid present for no apparent reason. ( Everyone please know I work closely with a terrific vet) and part of it was stupid Fedex not delivering semen on time. But oh glory day, she finally conceived in AUGUST and then with not 1, not 2, but THREE babies! One was clearly being absorbed at the time of U/S. Thank God, the second also naturally absorbed. And you can bet your butt I’m not taking any chances with the precious last one. Her last U/S was at 84 days, a healthy, feisty jumper to be, exercising those jumping legs clearly <3 . I still have her on Regumate and its day 115. I have been recommended to either pull her off at day 125 or to just keep her on it as a non-scientific insurance policy. So, I am very interested how this turned out for you, as I am now faced with a big decision.

[Montanas_Girl]

This is an 8 year old thread, and the OP hasn’t posted on COTH in more than two years, so I suspect you won’t get an answer from her.

You may find this article on the (mis)use of Regumate helpful, though: https://equine-reproduction.com/articles/mares/regumate.

Good luck with your mare! It sounds like you’ve been working hard to get this baby. You may consider joining in on our annual “foal watch” thread to commiserate and celebrate with the rest of us on this breeding journey.

[CuriosoJorge]

@kathy_s

when she ovulates give her a post breeding antibiotic treatment

This is terrible antibiotic stewardship. A flush, with no antibiotics, would be a far better choice if you were concerned about fluid retention.

This is a great example of why lay people (including stallion owners) doing their own repro work is a bad idea in many cases.

[CuriosoJorge]

@RyTimMick

If your mare has fluid, or edema, or poor conformation, you need the Regumate regardless of progesterone levels.

This is 100% false. See my previous post re: non-DVM stallion owners providing medical advice.

A mare with fluid needs a flush and an oxytocin protocol.

Edema is a normal finding in the dorsal horn of the uterus at preg check time.

And mares with poor conformation need a Caslick’s, not progesterone supplementation.