This is an archived Horseadvice.com Discussion. The parent article and menus are available on the navigation menu below:
HorseAdvice.com » Treatments and Medications for Horses » Reproductive Drugs » Dinoprost, Lutalyse, Synchrocept »
  Discussion on Lutalyse with follicle already present
Author Message
Member:
Levichey

Posted on Thursday, May 29, 2003 - 10:30 pm:

I have a question to reassure me of what I was told by a vet today. I have a mare that is difficult sometimes to catch in heat. I had her ultrasounded today to try to see where approximately she is in her cycle. Upon palpation, he said that one ovary was a little larger than the other and that her cervix was beginning to soften. The ultrasound showed a follicle about 20 mm. He suggested that I wait until Saturday (2 days) and give her a shot of Lutalyse and then she should be ready to breed by Monday or Tuesday. This stuff confuses me anyway, but this made it worse. If she already has a follicle, doesn't that mean that she is already in the process of coming into "heat". If so, what would giving the lutalyse at this point do? I thought it was for mares in diestrous to bring them into estrus.
Moderator:
DrO

Posted on Friday, May 30, 2003 - 5:25 am:

The idea is that it will hasten involution of the corpus luteum (CL), or involute a persistant CL. I tend to agree with you however: unless you have a reason to suspect something wrong with her cycling, it may be a touch of overkill.
DrO
Member:
Levichey

Posted on Friday, May 30, 2003 - 8:32 am:

So, without giving her the shot, when do you think she would be ready to breed? She had a foal on April 23 and I was planning on breeding her back on her second heat. She was 30 days last weekend, but wanted nothing to do with the stallion even through day 32. That was why I had her checked to try to figure out where in her cycle she was. I guess she is just a little later than average.
Moderator:
DrO

Posted on Saturday, May 31, 2003 - 9:34 am:

We carefully explain heat and ovulation predicition by a number of means including folliculr size at, Equine Reproduction » Breeding and Foaling » Heat (Estrus) Detection, Ovulation Prediction, and Timing Insemination. It should answer your questions and provide more background.
DrO
Member:
Bevpolo

Posted on Sunday, Jun 1, 2003 - 8:51 pm:

Paula,
I use lutalyse frequently, but never when a mare already has a follicle. I will use lutalyse to short cycle the mare after a foal heat so I do not have to wait for the 30 day heat to breed. Or I will do it when a mare just has no follicular activity. I have also done it in one case where I ended up with two embryos and wanted to abort and rebreed. I would never lutalyse a mare with a 20mm follicle however. All mares are different in the speed of maturation but in most cases, a 20mm follicle will not take longer than a week to mature. I have had a few odd cases where they will digress with severe changes of weather or a stressful event occurs with the mare. However, a 20mm follicle on Friday could easily be a 35-40mm on its own by Monday.
In your case, using lutalyse may bring on the follicle too quickly, which means by the time you read this it could be too late, and you miss breeding. You expressed concern about her passing 30 days and that by no means is a set number for a mare. Each mare is different. The 20mm follicle appears to be her 'second heat.'
Let me know what happens...I would be interested to see how fast she comes on with the lutalyse, if you gave it to her.
Bev
Moderator:
DrO

Posted on Monday, Jun 2, 2003 - 3:19 pm:

Hello B,
If your position that there is a whole lot of Lutalyse or othe PgF2a product given uneccasarily, you have my whole hearted agreement. But occasionally there is a need in a mare with a 20 mm follicle.

Persistant CL's (whether due to late diestral ovulations or those resistant to the natural resolution mechanism) will prevent a mare from returning to heat in a timely manner. However these persistant CL's do not prevent follicular development to 20mm or larger. I am not aware that the PgF2a will hasten ovulation when given to a normal mare already entering the early stages of estrus.
DrO
Member:
Levichey

Posted on Monday, Jun 2, 2003 - 3:22 pm:

Thanks for all the advice and info. I chose not to give the mare the shot of lutalyse. I took her to the stud Saturday and although she showed some slight signs of heat, she would not stand for the stud. Sunday, she showed a little stronger, but still wasn't willing. I've not heard from the stud owners today, but hopefully she is getting close to standing. I will let you know for sure how it turns out.
Member:
Bevpolo

Posted on Monday, Jun 2, 2003 - 4:04 pm:

Dr. O & Paula,
definitely agree that lutalyse is the way to go with persistant CL's...however, with just one palpation, or ultrasound in Paula's case, how do we know that is a persistant CL and not a follicle coming on? I would have had the mare palpated again on Saturday to see progession.
Ultimately, the lutalyse probably would not have done any harm, or as you said it would not have hastened the ovulation. But what is the point when she is doing fine on her own?
From what Paula says about her teasing patterns, the follicle is coming on nicely and hopefully they will hit breeding with a soft 45+! Let's hope that is what happens!
Paula, let us know what day she is bred...and you may want to palpate her to confirm ovulation!
My best, Bev
Member:
Levichey

Posted on Thursday, Jun 5, 2003 - 9:05 pm:

Thought I would let you know the outcome of this story. The mare never would stand for the stud and by yesterday (Wednesday) she was getting down right ill towards him. Today she was palpated and ultrasounded again and her follicle is still there and is still only about 2.5 cm. Apparently it is just stuck at that point. Anyway, my next move is 10 days of Regumate followed by a shot of Lutalyse on day 11 to try to get her to cycle.

Paula
Moderator:
DrO

Posted on Friday, Jun 6, 2003 - 3:06 pm:

Bummer Paula,
Why the regumate, why not just go ahead with the lutalyse if he suspects a persistant CL, by waiting and monitoring you have increased the chance it may help this mare.
Member:
Bevpolo

Posted on Friday, Jun 6, 2003 - 4:16 pm:

Paula, that was my question too...why the regumate? I was waiting for Dr. O to say it first! I think you need to try and get her palpated a litte more often. You would not have had to wait all those days relying on the teaser to tell you what was going on. Lutalyse her and palpate her on the fifth day after the shot and then every other day so you can really monitor the activity. That way she doesn't have to sit around at the breeding shed spending your board money!
Best of luck! Bev
Member:
Levichey

Posted on Monday, Jun 9, 2003 - 8:23 am:

I guess he was just trying to regulate her hormones. This was the same process that I went through the first year I bred her to get her to stand. I gave her 3 lutalyse shots that year with no luck, but when I did the Regumate followed by the lutalyse, she came right in and was bred. Oh, and she's at home until she gets through with this regumine of hormones then I will take her back on about the fourth day after the lutalyse shot. It's only about 20 miles to the stud. This is her third year being bred. The first year I had these problems, the second year I bred her on foal heat and she bred like a dream and this year she is exactly like she was the first year. I guess since the Regumate followed by Lutalyse worked so well the first time, I didn't question trying it again.

Paula
Member:
Levichey

Posted on Wednesday, Jun 25, 2003 - 12:03 pm:

Just wanted to let you all know the outcome, so far, since I started this discussion. I continued with the Regumate followed by the lutalyse shot, took the mare back to the stud on day 4 after the shot, and finally on day 6, she decided she was ready to stand to breed! She has bred 3 days so far. Hopefully in a few weeks an ultrsound will show a successful breeding.

Paula
Moderator:
DrO

Posted on Thursday, Jun 26, 2003 - 6:40 am:

Thanks Paula,
Do let us know if she settles.
DrO
Member:
Levichey

Posted on Thursday, Jul 31, 2003 - 2:22 pm:

Sorry that I am only now updating you on the fact that my mare did get with foal. I had her checked on day 17 and she was bred. Maybe I ended up taking the long way around, but it was successful, and hopefully next year I will have another healthy foal. Thanks for all of your advice.
Home Page | Top of Page | Join Us!
Horseadvice.com is a BBB Accredited Business. Click for the BBB Business Review of this Horse Training in Stokesdale NC