OK, greetings everybody, today we're going to talk about twin detection, management and how to avoid missing twins in the mare. This is one of my favourite presentations because I, I firmly believe it's, it's really important because multiple ovulation, that's ovulation of more than one follicle, is common in, in mares, in, in all mares, particularly thoroughbred mares and, and then down to warm-blood mares, less common in certain other types, particularly ponies. But typically a thoroughbred mare may have a multiple ovulation.
More than 30% of cycles, which makes the detection of twins and their subsequent management and avoiding not detecting them, very, very important for us in equine reproduction, whether we're doing large numbers or small numbers. So I hope you'll enjoy the session, and again, those of you who have listened to me before or. See me give a presentation back in the old days.
You'll know, I, I, I try and tell the, the story with, with, cases that have happened, to, to me in my daily work, which I think is a good way of explaining things rather than being too didactic. So, hopefully it'll be relatively easy on the ear and eye to listen to. Just briefly, I set up equine reproductive services around about 25 years ago now, it's just me, now it's grown to 6 permanent vets and and more during the breeding season.
I've stepped back somewhat and take a consultancy role, and, those folks you can see on screen there, particularly those two gentlemen on the top, Jimmy Crabtree and Charlie Cook, they, run. The practise now and I just pop in from time to time to annoy them. For more information, there are books obviously in this short period of time, 50 minutes an hour or so, we can't get through everything.
So again, you'll find some more information in current therapy and equine reproduction. And a little self-assessment book is, is quite fun to, do some cases and, Juan Samper's equine breeding Management and artificial insemination. Couple of other books, of course, the big, tone from Angus McKinnon and er and colleagues on equine reproduction, and then, an interesting atlas of equine ultrasonography, a largely pictorial book which has a, a section on normal reproduction and, I did a section on equine .
Subfertility fertility problems abnormal reproductive ultrasonography so. Onto today's topic. Let's start with the question, and those of you who are watching this pre-recorded, as you know, you can pause it, of course, if you want to, you know, if you're doing it in a practise lunch meeting or evening meeting or something and want to pause and have a think, you can of course do that.
So the question I'm posing is what is the best time to perform the first scan for pregnancy? 12 to 13 days from ovulation, 14 to 1517 to 18 from ovulation, or 15 to 16 from covering or insemination. You'll note that the first three refer to a time period specified with ovulation as the day zero or or start point, and, and 04 refers to 15 to 16 days from covering or insemination.
Now, I, I was gonna say I'm, I was fortunate in, in, in, in the vast majority of times I examined a mare. I was generally follicle testing, you know, evaluating that mare during the follicular phase, so I would know. The date she ovulated and I could often go to stud farms every day, so I could generally predict ovulation with a good deal of accuracy within a 12 to 18 hour window, so I could know when the mayor was 15 days from ovulation, or 18 days from ovulation.
You may not always know that, and, and, and of course, perhaps if a mayor's been getting inseminated or bred away from your practise and comes home to have the first pregnancy scan, maybe you'll get ovulation data, maybe you just have to do your first scan when she's a number of days from covering or insemination. So, when is the best time to perform the first scan for pregnancy? Well, I think the answer would really be 14 to 15 days from ovulation.
Of course, if, if you've only got covering or insemination date, then, then answer 4 would probably be correct, but the best time, and, and that was maybe a little bit of a sneaky word to add into the question, the best time to perform it is, in my book, 14 to 15 days from ovulation, because 15 to 16 days from covering or insemination presumes. That the mare will ovulate, you know, a day or so after breeding, which is not, of course, always the case. So I prefer to base my first scan for pregnancy on a known ovulation date, a number of days from a known ovulation date and the number of days is best to be.
14 or 15. So I hope that makes sense. I'm sure most of you probably knew that, wherever I was when I last polled this question, 50% of the audience did get what I would consider to be the correct answer.
So, let's get that established now. The the first scan for pregnancy is usually performed 140 to 15 days after ovulation, and there's a pregnancy in the bottom right of the screen there. We're not gonna, you know, we, we're not doing a talk solely on pregnancy, in fact, not really on pregnancy, but we obviously have to imagine.
We have to introduce the concept if we're gonna talk about twin management, but at 14 days, after ovulation, if the mare is pregnant, what we see is, correctly termed the conceptus, rather than an embryo, the conceptus, and there, bottom right is a 14 day conceptus measuring, it's gonna be around about 1618 millimetres in diameter, and it has a pretty good spherical shape at this stage. Important to remember, and we'll come back to this when we talk about twin management, is that the pregnancy is highly mobile at this stage. Now that means when you're conducting your ultrasound exam, and I'll illustrate this by way of reference to some video scans of pregnancy, which I'll, I'll I'll show you, share with you, it makes it very important, this mobility, that you are conscientious in your pregnancy examination to carefully check both the left and the right uterine horn and the uterine body in its entirety.
That's very, very important. You must do that methodically. I actually do it twice.
I go up. My routine is always to take the transducer in, locate the base of the left uterine horn, go up the left uterine horn on the left over, evaluate that, back down the left uterine horn. Then go up the right uterine horn onto the right ovary, check the right ovary out, then I repeat the process again, and then as I'm withdrawing the transducer, very carefully examine the uterine body by sweeping from side to side.
And I think that will be illustrated in the videos we'll show you. Now, another important concept which we must understand when we're talking about twin management is fixation. We could define fixation as the cessation, the stopping of mobility of the conceptors.
As everything in, in, in, in nature, there are variations in the precise time, but nonetheless to work with, a subject, I think we have to have some, time scale and time framework, and I think we can say in general terms, fixation occurs around about day 16 after ovulation. So, one of the conceptuses will be fixed at either the base of the left horn, the flexure at the base of the left uterine horn, or the base of the right uterine horn. Now that's for a single pregnancy.
If we're dealing with a twin pregnancy, when obviously there are going to be two of these conceptuses, they could be both at the base of the left horn, both at the base of the right horn. One at the base of the left horn and one at the base of the right horn. And if they're both fixed together at the base of the same uterine horn, well, we term that unilateral fixation.
And if one is fixated at the base of the left horn, the other at the base of the right horn, we term that. Bilateral, and that's important because we have a different approach to management of twins, after a certain stage, after fixation, depending on whether they are fixed unilaterally or they are fixed bilaterally. Good.
Hope you're all with me so far. We're often asked, our, our colleagues often ask me about timing of pregnancy scans. There isn't a set.
Pattern when you should do your 2nd and 3rd scans, if you're able to do a 3rd scan. I can, I can only really tell you what we do in our practise in the majority of situations. We would do the 2nd scan, maybe we'd actually do it around about 23, 24, 25 days, perhaps a little bit earlier than 25 days, or, or should we say, the second scan, no later than 25 days after ovulation.
We try and do a 3rd scan around about day 33 or day 34, and generally unless the mayor is having a. A foetal sexing performed, she'll then go home after that 3rd pregnancy scan. Nonetheless, the timings are arbitrary, and of course, it's important to understand that if your mayor has many endometrial cysts, and I'll show you a video coming up of a mayor with endometrial cysts, well, we may feel that we need to do more because we may be more concerned.
The early pregnancy may be lost, or we may be having difficulty deciding whether we're dealing with a mare with a twin pregnancy, or a mare with a single pregnancy and a cyst, and clearly it's very, very important to make sure that you're correct in the decision you're making. As ever, in many things we do in veterinary practise. Economics will be a factor, the more valuable the mayor and the more expensive the breathing fee, the more likely it is an owner is going to be content for you to do 3 pregnancy scans.
So ideally, we like to do 3 early pregnancy diagnoses, but we recognise that may not always be possible. However, if you only perform 1 ultrasound scan for pregnancy. We think it's important that you tell the owner, that's fine if you want to do that, but it is specifically against veterinary advice and we warn them that this will increase the risk of missing a twin.
And as a. A security measure to make sure that message is understood, we record that this advice was given in that mayor's record or clinical notes. And then if sadly in 7 or 8 months' time, the mayor does abort twins and you can check back your notes, you can say Well, I did say that we only did one scan, and you were advised to have a second scan, and you chose to decline that.
So we think that's an important thing to record. Why is twinning undesirable? I'm sure many of you know.
Abortion is generally what occurs. Typically late gestation, 78 months, you get one of the pregnancies, is essentially normal for a for a 78 month gestation, because it's developed in one uterine horn and the uterine body. Unfortunately, the second co-twin generally only develops in one of the horns, so when it gets to about 7 or 8 months, generally too big for that amount of endometrium to support it, so it dies.
And then because of the endocrinology of late pregnancy in the mare, both are aborted, and it clearly is distressing for all concerned really, particularly the mayor herself and the owner. And the mare can be difficult, particularly if she was she aborted relatively, you know, into the middle of the following breeding season, let's say for northern hemisphere, she Loses that pregnancy in April, May, June, well, she may be difficult to get back in foal that year because both, you know, horns of the uterus have been stretched and mares normally become pregnant in the You try and horn it, the pregnancy fixes it in in in the uterine horn, which they weren't in foal in the year. Previously.
And I don't want to get into placentology in the mare or placenation, but, basically, there's generally insufficient area of uterus for the placentas to attach to. And as we said, one foetus usually becomes larger than the other, essentially normal size, and, and when the smaller one, when it's co-twin dies, both become aborted and. That's obviously distressing.
Occasionally, if, again, it, it, it generally occurs when the uterine body carries, is split into two, as it were, in in terms of placenation. So one twin develops in the left uterine or and half the uterine. The, the other in, the other half of the uterine body and the right uterine norm, which is less common than the scenario we just presented there where, one co-twin occupies all the uterine body in one of the horns and the other one just the uterine horn.
But in this other situation, we can get twins born, but, often one of them dies, and even if both survive, they often have problems with, you know, immature bones and don't perform well as athletes, and so on and so forth. So, I think for all those reasons, carrying a twin pregnancy is dangerous for the mare, as it can cause dystopia. So, I put that point in or these points in, because, not unreasonable, occasionally an owner feels when we, we, we scan them out 15 days and detect twins, and we sometimes rather blase, it's all right well we're going to crush one.
Sometimes we, we just, particularly we've got an owner who's less experienced with breeding, we may need to explain the process why we feel that that's a. Good idea to do, and those are the reasons why we shouldn't allow a mare forward carrying twins because of those reasons. Now I, I, you'll you'll detect there's in a smaller font there, but I've put twin pregnancies almost.
Always arise when more than one follicle ruptures at ovulation. There are reports of twin pregnancies arising from single ov ovulations, but they are very, very rare, so, In 99.9% of cases, we will be able to identify on the pregnancy scan, two distinct corporal lutea present arising from the two ovulations which have both released our cys to court.
The twin pregnancy. Now, the ovulations may be within a reasonably close period of time, which typically within 48 hours we term a synchronous ovulation, multiple ovulation, or if one follicle ovulates, 48 hours or more after the other one, then we term that an asynchronous ovulation, and they are the twin pregnancies where we may see one conceptus considerably smaller than the other, simply because it arose from an ovulation 3 or 4 days after the first ovulation. And we'll come back to that point again when I show you the video clips.
So 2 ocytes are fertilised and a twin pregnancy is formed. Now, obviously, a mare which has a multiple ovulation may only become in foal with a singleton. Indeed, it may even become not in foul.
Barrett may not, may not conceive. So multiple ovulation. Two follicles, two ocytes being released does not equate to a definite twin pregnancy, but, the converse is generally true.
In 99.9% of cases where we have a twin pregnancy, there will have been two distinct follicles ovulating. So here we see probably this is a twin pregnancy, two perfect spheres.
You can see the typical specular reflections, we call them, they're just a physical feature we see on the ultrasound screen when we going back 30 years when we first began scanning mares for pregnancy, we erroneously sometimes thought these represented the. A conceptus or or embryo or something, well, they don't, they just because this is a perfect sphere, without going into the physics of ultrasound, you'll often get these hyperrechoic lines at the top and bottom. These two conceptuses, one there, one there, probably there's a day, or maybe even a day and a half difference between these two in when the follicles ovulate, which led to their.
Conception. So if we look at a video clip, you may remember, I don't edit my video clips, so they can be a little bit tricky to follow, but you can freeze them if you want. And I always do the same routine.
I'm going up the left uterine horn now I'm gonna come up the left ovary in a minute. There's the left ovary, what can we see? Pingo, 2.
Corporal Lutia, you see those one there with a bit of a lacuna, second CL there. Yeah, had a look. 2 CLs going back down the left uterine horn.
Oh, what's that? Cyst, not a pregnancy, that's a cyst. Another endometrial cyst.
Another cyst, plenty of cysts in this man. Another cyst. I haven't seen a ah ha, now, that's looking better.
00, have we got a little twin? No, don't think so. Oh, we had two CLs though, are we sure?
Cyst up there, nothing on the right ovary. Right, I'm gonna go back down. Cyst, not worried about that.
Oh, well there's that, no, that is a cyst. Now there's our pregnancy. So, OK, folks, we've had 2 CLs.
Checking the body on the way out, I want to get ahead of myself. There I am sweeping side to side utron body and out, so good. That was an interesting 12 CLs, plenty of endometrial cysts, only one conceptus.
Oh, we'd better be right. I tell you, I'm pretty comfortable I was right with that, so I may just have fitted that into our normal checklist mayor out in day 24, day 25, so we would probably put C10 in the notes. Now.
If we weren't sure that there was, those ovulations may have been more than 2 or 3 days apart, so when we see that 15 day conceptus, maybe there's a 12 day somewhere. Perhaps I might put in, let's check this mare again in 3 or 4 days. So that can be a perfectly good system to do if you have a mare with two ovulations, you scan her very carefully, you can only see one.
If you go back to your follicle evaluation, and there's a possibility that the Two follicles ovulated more than 3 or 4 days apart and you're using natural covering where sperm lives long enough to fertilise both of them. Maybe to be safe, let's put C3 or C4, and let's just check that mare in 4 days' time. To just make sure there only is one pregnancy, developing and a little sneaky twin who was only day 11 or day 12 when we looked, when one was day 15, has, has come along, and we need to be.
Aware of that. If we scan them out at 15 days, we can manage twin pregnancies, once we've got a deal of experience at looking at them and evaluating them and managing them, we can massage one of the pregnancies away from the other using gentle pressure, from the transducer. I've put there all the operator's fingers in a smaller case, font.
I don't think many. Veterinarians do use the thing. I think most are like me and all thinking, all of the colleagues in our practise, we use the transducer, the ultrasound probe, if you will, to position it down in between there and move these two conceptuses apart.
I'm gonna try and show you in a video clip, a little bit difficult to show because of course, You know, once you move them away, it's a bit hard to orientate quite what's going on, but we'll have a look at that. And yeah, I put 95% success, I mean, in truth. I, I, I think we, we have a, almost a 100% success rate with managing twins in this way.
That does not mean every one of these pregnancies will carry through to term with a singleton after we've crushed one of the concepts, because we get the embryonic loss, which, an early pregnancy failure which we talked about in a previous webinar, in this series. So, it does, you know, 100% success means when I came along, 3 or 4 days later, which is what I usually do to check there's just one developing, it's, it's extremely unusual for both to have gone, in, in our experience, these days. Once the sphere's been moved apart, you, you'll only generally find you need light pressure to crush one of them, and in most cases, you're aware there is a popping sensation.
Just occasionally I'm merely moving the transducer, almost just beginning. The moving apart process and 01 of them may rupture, that always worries me a little bit, because I think, oh gosh, you know, they are, they are very, very easily damaged. I, I wonder to myself, and, and we've wondered in the practise, don't know for sure, maybe that, maybe that conceptus was.
Sort of, on its way out, likely to be resolved in any case, but that's a little bit of. Practitioner anecdote musing there rather than. Hard facts.
So another little video clip. So this'll fire up in a minute, we'll go away. Same system.
I'm gonna ping up the left uterine horn, yep, a little bit. There's the left uterine orchid in the middle of the screen, look on the left ovary. Nothing much on that left ovary, don't think that's a CL.
It was just stroma coming down the left horn again, through the body, base of right, yeah, yeah, yeah, yeah. And then now, do you see that sort of bit like a dumbbell type thing there. Fashion, or not old fashion, but weights you live.
That flickering, looks like a flicker, but you could see that line between the two of them. That is a twin pregnancy. There's gonna be two CLs in this mess right over and sure enough, there are two corpra lutea there.
Back down to look at this twin pregnancy, there we go. Now I'm beginning to crush one, times we've got to get on, so, as I say, these are real life video clips we're taking in. Stud farm situations that people are wanting us to get on there, I'm moving one, crushing it and I've I I I've actually crushed one, a little bit of fluid running down there.
It's kind of hard to see, I know, but . That's what we did then. I just checked the, see a little bit of edoema pattern has appeared.
I think that's with the manipulation. There's the fluid, it's a bit of a worry, the fluid running around the other, but I think in that smallish volume doesn't seem to matter. It's checking the body on the way out, so that was a video of it twin crush.
Now. A good friend of mine, Angus McKinnon, a few years ago, came to do a talk at the British Equine Veterinary Association on twin pregnancy. And Angus did this video, and I think it's a a useful video to show you, he's he's trying to explain on a PM tract how that process works.
So he's moved one of the concepts is to the tip of the left or right uterine horn, he's showing both there. He's sort of exaggerating that flicking movement down you need to do. But nonetheless, I think that's an interesting, should we, should we, let's see if we can give that a little rerun there.
So that's if if you have to crush one in the body first. Then he's going on to the right uterine horn, moving the conceptus up there, up there. And then it's running out of room.
I generally just would carry on a bit, and I find that crushes it really against the, when it runs out to you to try and horn in essence. So, you, you, I, I, I know Angus is keen on demonstrating that, sort of rather exaggerated flicking movement. I've, I've, I'm not not sure you've to do perhaps as much, but, but often when we're making a video, we want to kind of show.
You know, show it a little bit obvious, so we're all aware of it, so yeah, great little video clip, thank you. Oh chum for that. What drugs are given after a twin crush?
Well, I'll, I'll pose as a question. Progesterone and altranoest are progetogen, non-steroidal anti-inflammatories, that's what NSAID is, sorry for using abbreviations, non-steroidals, but most of you will know that I'm sure, non antibiotics. Now, I don't know where.
Goodness me, I've forgotten wherever I was when we used to be able to go and see people. I would poll this question. And look, a good half of people gave a progesterone alrenoest after a twin crush.
Small number gave a non-steroidal, a good number, 1/3 of you gave none. And a small percentage antibiotics, now. There isn't a right or wrong answer here.
I'll tell you what I do. I generally don't give anything after a twin crush. So I'd be in the 36%, but if you're crushing, manually reducing twins, crushing them.
And, and put that there on renegist for a few days or whatever, or you give a shot of banamine, phinidine, flunixin. Well, I'm not gonna tell you to stop doing that, I'm just telling you that what I do, because I'm an honest soul, so I generally give no drugs after twin crush. Fixation, we sort of touched on this, and I don't want to get bogged down in this, this sort of wonderful image there from Ollie Ginther's book, bilateral versus unilateral, so bilateral is when you get one at the base of the left horn and one at the base of the right.
So this would be, Bilateral, and it's the smaller percentage, around about 1/3, so 2/3 unilateral, 1/3 only bilateral. So the majority of twins fix unilaterally in the same side, the base of the left or the base of the right. And that is why, everybody, we generally take action before this fixation.
OK? We generally take action before fixation. Because if we wait till fixation, especially as 2/3 are gonna fix at the base of the same horn, we're gonna face a difficulty.
It isn't as simple as just putting the transducer between them and moving them apart, because that ain't gonna happen after fixation, or it certainly isn't gonna happen very easily. And there's gonna be a risk of damaging both of the pregnancies, so take action before fixation, OK? So, up until day 1516, we, we, we've got, got it fixed, doesn't matter if it's unilateral or bilateral, we'll be able to put the transducer in between the two pregnancies, move them apart and, and successfully crush one.
So, let's look about management of twins after day 17, because you've got a view, you know, you can't just say, well, you manage twins by crushing one of them. Yeah, that's fine up until fixation. It may not be the case that you're able to do that after fixation.
So the management after day 1717 days after ovulation. When you first detect them, depends on whether you've got these twin pregnancies, unilateral, both at the base of the left or the base of the right horn, or they are bilateral. And the other factor, depending on when you first detect pregnancy in this mare, when it's first presented to you, you've got to bear in mind that from around about.
Day 30 onwards, you know, debate about when it first appears and when it's a significant amount, but let's go from around about 30 days of pregnancy, ECG, equine, chorionic gonadotrophin forms, and without going into detailed endocrinology, what that effectively means is it will Stop the mare having a fertile follicular phase, estru cycle for some weeks, even months. So that is a little bit of make your mind up time. We, we've got to get our decision made what we're doing before endometrial cup formation, because after endometrial cup formation, our options to recycle that mare and breed her again become very limited for that breeding season.
OK, so, unilateral, so I'm defining these as unilateral. They're both at the base of the left horn, or both, both at the base of the right horn. They are fixed together.
Well, OK, we can try and crush one. If you're on day 17. Yeah, maybe.
Day 18, maybe. Once you start getting past day 18 unilaterals, you're gonna struggle to try and crush one in my book. You could leave and monitor them.
Indefinitely or not, oh, Leave and monitoring until day 30. Give PG straight away. Why might I have picked day 30, do you think?
Well, that's connected to the equine ch chorionic gonadotrophy I've just been talking about. If we find we've still got at day 30 when we scan that mare, two concepts will be embryos by then, so two embryos with a heartbeat, both at the base of the left or or the base of the right horn, if we want to re-breed that mare, and by giving a prostaglandin, we don't want to leave it much, if any, beyond day 30. So it's quite a bit to think about in that slide, maybe if you want .
To revisit this, talk, and, and check, check it at a later stage, whether you can get this answer correct or not, or you may want to pause it as you're going through and have a bit of debate in the practise, whatever, because there's quite a bit of information here in this slide, to think about, and it's worth having a think about it. Try and crush one. Well, the vast majority of people I polled for this went for that, and, and, yeah, that's fine and dandy if it's around about day 17 or day 18.
I, I think you'll just struggle to try and crush one beyond day 19 successfully, but on the other hand, at least you're getting a decision made, and you're going to be able to recycle that mare, if they, if, if the twin crush hasn't worked and you've lost both of them. When you rescanner, say, 3 or 4 days later, as we usually do after a twin crush, both have gone, well, if the mayor doesn't show signs of coming back into a follicular phase, we can give a prostaglandin, and we can re-breed that mare because we're only going to be at round about day 20, day 21, day 22. Leave and monitor, not really very attractive to me, I, I mean, you could do.
I, I, I think if you've got two, you know, decent sized unilateral twins at day 1819, . The vast majority of times at day 30, you'll still have two healthy growing twins. If you're gonna do anything on the leave and monitor front.
I'd probably not go beyond day 30 for the, for the reason I mentioned earlier, equine chorionic gonadotrophin. Give prostaglandin straight away. Well, I mean, you might as well try and crush one, hadn't you?
So I think it's quite understandable, that's why nobody went for the give PG straight away. So, that was, . Doing nothing and monitoring is an option.
Well, when reduction occurs, it's usually before we've got both embryos, so, you know, OK, scanner up to day 21, 22. But if you've got two embryos formed, I wouldn't personally carry on scanning them there after that, I would prostaglandin and start again. And attempt reduction, yes, I mean you can do if, if it doesn't work well, at least you can start again.
I, I, I think what I don't like doing with, with, with unilateral twins, twins fixing in the same. Base of left or base of right on is, is, is waiting too long, much beyond day 25, day 26. Let's crack on and start again and, and, and try and deal with them effectively if she does, the mayor does produce a twin pregnancy next time, by our more normal or more or better probably I should say, approach which is .
Reducing them on a day 15 scan when we can when when we can, even if they are fixed in the base on the left or right or, as they may often be, we can still move them apart. Now bilateral, let, let, what it, so we've changed now, now we're talking about twins where one is at the base of the left horn, one is at the base of the right horn. Crush one up to day 25, is that a good option?
Crush 1 up to day 30, 1 up to day 35, Prostaglandin immediately, monitor for natural reduction. There's gonna be a difference here in our in our answer, because there is a different approach to unilateral twins after day 17 to bilateral twins after day 17. Bilateral twins, after day 17.
We can crush one pretty effectively up into day 30, and yes, OK, there's a fair bit of fluid appears from it, might run around the remaining conceptus pregnancy, even at that stage a little bit. Could put her on progesterone if we've got real concerns, we'll keep monitoring to make sure the CL. Remains visible.
So crush one up to day 30, that would be my choice. Why don't I like crushing one up to day 35? We may not have been producing endometrial, or there may not be endometrial cups producing equine chorionic trophin by then, .
I just think after day 30, there does get each day more and more fluid in that, in, in that, in that stage of pregnancy, and I think if you crush them at day 35, A, you'll find you'll need quite a bit of force, and, and goodness me, what we don't want to do is damage the mire. So not only do you need a, you know, a worrying amount of force on some occasions to try and crush one at day 35, there is also an awful lot of fluid. So I think, Day 30, even with bilateral twins that you've detected, is make your mind up time.
Let's do something by day 30, and that, that should, with luck and a fair wind, leave us an option to re-breed the mare that same season if, our crushing procedure doesn't work. So I would be in group 2, as the majority of people were on that occasion. Good.
So, to summarise that, I guess bilaterally eliminate one of the twins immediately upon detection up to day 30, and, and that bullet point is, is my view on it. After 31 days, I think there's a reduced likelihood of survivor, the remaining pregnancy, so much fluid produced from the the the the the conceptus pregnancy you've crushed, it'll just damage the remaining pregnancy. And I think there's a, a, a risk of damaging the mare, relatively small, but I just don't think we can take that risk.
So, for me personally, I won't do a manual rupture after day 30. There are two approaches. I, I prefer transvaginal ultrasound guided aspiration.
Most of my colleagues are just thinking then in the practise, prefer craniocervical dislocation. I, I worked for a, for a, a couple of years at the vet school in Utrecht where we were on a project of harvesting oocytes out of follicles, so I got. Relatively skillful at manipulating needles within the reproductive tract of the mare, so, I, I, I, I, I feel pretty comfortable about being able to guide a needle into One of a twin, after day 30, so that's, that's just a background why I most, I don't think many people are doing transvaginal ultrasound guided aspiration these days.
And importantly remember in, in every case, it's when, for whatever reason. That the simpler management of crushing one at day 15 didn't happen. OK.
How are we going, everybody? Just let me take a slug of. Tea there, good old Yorkshire tea.
Other teas are available. Twin pregnancy treatment, right, OK, after the day, probably should put day 30 there, I think, if, if I'm, if I'm being being right, because I, I, I've sort of got more nervous about leaving dealing with it until . Until, endometrial cup formation.
So once we go, you know. To that day 35 time frame. What I, what I was meaning there was, if, if we're going to do a more straightforward technique, like trying to manually rupture them, do that before day 30, rather than even before day 35.
Once we've got, after day 30, 35, this transvaginal ultrasound guided needle puncture. Is my chosen technique. This is, you need a bit of apparatus so you can see we've got, I'm not gonna go into this in great detail, but you can see that this is what we call a needle holder.
Obviously while we're inserting this, it's transvaginal as you would guess from the name, clearly, obviously, I have this, this, this needle retracted within this needle holder, and bits of tubing we'll talk about here. Maybe to explain it a little bit more. There you can see, we can get across the screen these broken lines.
This is a day, I, I can't honestly remember now, I imagine this will be about a day 40, 45 pregnancy. There you can, this tells me where the needle tip is gonna be directed when I do decide to push it through. So with my left hand, I'm holding the uterus firmly against the edge of this transvaginal ultrasound probe.
And I try and position it so that the embryo itself within the concept is located along these dotted lines and I can push this needle in and I can damage one of the co-twins and hopefully leave the other. Intact. Now you can see, this would be the needle tip, so I can tell where it is on the screen.
This broken line indicates the direction, some of it, you may wonder, this is a little coating to make that needle tip particularly visible on ultrasound. So that's good on the one hand, but you've got to remember the tip itself, generally, just a little bit further on from where you can see that mark on the screen. And if we show you, I I haven't actually got this is one without, we actually know where the dots are gonna be, it's gonna come in there, so you'll.
You'll see it in a minute. There's that. There you can see the needle, so I'm withdrawing some fluid, you see it's losing its shape.
I haven't actually managed to get the embryo itself here. You can see I'm removing fluid there. Shrinking down, shrinking down.
Hopefully, you know, I, I, I, I think it is, it's a little bit, I mean it sounds a little bit gruesome, but for the reasons I explained, it we can't really leave the mare carrying twins, because it's dangerous for her, . And it's unlikely to work. Now I now I'm actually contacting the embryo, you see, with that needle tip.
Very little fluid left within this pregnancy. So, that's transvaginal ultrasound guided aspiration, hopefully leaves the other one intact. What my colleagues tend to do is cranial cervical dislocation.
I think the early reports were described being able to dislocate the head per rectum. I know Jimmy Crabtree, who uses it mainly in our practise, much prefers to do the, dislocation via a laparotomy incision, and there's no, I sort of Clean way of putting it, then you, you sort of dislocate the head from the neck of one of the foetuses. So, as I say, this is Jimmy doing one, A laparotomy, I don't, I don't know enough about the technique whether some people are still having success with just doing it, via a, rectal approach, which obviously would be.
Less invasive, although a standing flank laparotomy isn't a, a huge procedure in the mare, . Post dislocation, well you can kind of see the head sort of detached a little bit from the body, so kind of slightly, slightly gruesome in some ways, you know, this sort of headless foetus, so I, I don't, I, I, I, I'll stick with transvaginal ultrasound guided aspiration. But just remember, folks who are watching this video play out, whatever, really, this is, is, is a salvage procedure when for whatever.
A reason, and there can be good reasons. Maybe you didn't detect them, maybe the mayor didn't get presented, whatevers. You didn't get that mayor to scan at 1415 days when it is relatively straightforward to deal with twins.
Now I'm one video clip which I'm gonna leave you with, cos I I think this is a fascinating little video clip. I might let it run without saying much about it, . And see what you make of it.
So I'm going up the left utine horn. Remember that I said my routine. This is a 15 day preg scan, 15 days I'll be like, oh, plenty of follicular development, but we don't worry about follicular development in a mere 15 days of pregnancy, as long as we can see a corpus luteum.
Oh, bingo, good stuff. We've got a 15 day pregnancy there. Great.
Fabuloso. There we go, check that out, can only see one going up the right uter on the right ovary. CL.
Yeah, have another look, Jono. Yeah, oh, how many CLs? How many CLs?
How many CLs, 212. Better go back, have a look at that pregnancy. Well, Better than man than me if you see 2 there, there's only 1 there, I think in my book now I'm checking the bodies that come out, yeah, finishing off la di da, let's get this transducer out, get on to the next mare.
Yeah, who spotted that, who didn't spot that and who did? Woo! What have we got there, little cyst, no siree, that ain't a cyst.
That is a day 12 conceptus. So I'd imagine this mayor would have a asynchronous ovulation from a rig which would give us those two CLs, probably 34 days apart, so probably we've been using natural covering. Because sperm wouldn't live, you know, with frozen semen, it wouldn't live the 4 day time interval between these two pregnancies, .
So I, I just thought, I, I, one of my favourite video clips and it's a salutary lesson for us, that you, boy you've gotta be careful, you don't miss a little twin in that uterine body and particularly if you're using natural covering, where we have this sperm living 2345 days in there, you know, be very, very careful, if you've got 2 CLs and you're saying you only see one pregnancy. If you knew there were synchronous ovulations, then that's fine and dandy, but if you, either you didn't know, or you were monitoring you saw there's an ovulation of potentially 3 or 4 days after the other, those are the mares which you do your first scan, 1415 days as usual, you probably would be well advised to throw in. a follow-up scan 3 or 4 days later.
Now in this mayor, what would we do? Let, let's let's think about that mayor we've just seen with that 15 day pregnancy and the 13th day, or probably 12 day actually, pregnancy in the body. Well, that pregnancy in the body, I can tell you is going to be very, very difficult to crush.
They're pretty robust when they're at that stage, and if you try and crush that with a transducer, that little pregnancy will just kind of flick around all over the place. It takes quite a bit of skill to, to crush a pregnancy that small, it's good if you can because very little fluid comes from it, and the other ones, 99.999 gonna be fine.
But it, it's a little bit tricky, so. Yeah, I, I may have a go. I might put, I might say to the stud farm, look, look, fellas, pull this mare back in in a couple of days.
By then we'll have a 13 day pregnancy, and I should be able to crush that easily enough. Or I'd maybe just pick it the next day if it was easy enough. If you've gone a long way out of town to visit this mayor, well, Maybe you're gonna have to make a fair effort to crush that smaller one, but it's gonna be at that stage that this one was, it's gonna be difficult, so, mm, you know.
Choices, choices, choices. Well, here we are, this is an activity we used to, well, we still could do this, I suppose, go skiing, but it's, it's, you'd have to walk all the way up and it couldn't be with 3 of you, of course, now, so probably not a good idea. It's 50 odd minutes has gone by, so I'm gonna draw this, to a halt and hope you've found that a useful webinar on twin detection, management, and avoiding.
Missing a twin. So thank you very much for your attention. And hope you found it useful.
Thank you.