Episode 203: TCI Retrospective Study Reveals Breeding Insights

Transcervical insemination has evolved to become an efficient breeding tool since its beginning in the 1970s. Joshua Trumble, DVM discusses a study conducted by theriogenologists at Ohio State University which looked at using semen and sedation types to predict pregnancy rate and litter size.

Watch the video version of this presentation here.

Transcript

Nicole Engelman  00:04

Welcome to the Good Dog Pod. Join us every other Wednesday when we discuss all things dogs, from health and veterinary care to training and behavior science, as well as the ins and outs of Good Dog and how our platform can help you successfully run your breeding program. Follow us and join Good Dog’s mission to build a better world for our dogs and the people who love them.

Nicole Engelman  00:28

Hi everyone. I'm Nicole. I'm Good Dog’s Community Lead, for those of you who don't know me. Thank you so much for joining us for today's presentation exploring TCI procedures for your program. We have a brand new guest joining us today for the first time. We're so excited to have him here, Dr. Joshua Trumble. Today, he is going to cover how transcervical insemination evolved to become a really efficient breeding tool since the beginnings in the 1970s and then he's also going to cover what you can expect during a procedure as well. Of course, we are so excited to partner with Purina to bring you this webinar. This is—again, I feel like I keep saying this every webinar we do, and I sound like a broken record, but this is a topic we have not yet covered before, haven't been able to in the past—so we're really excited that we've been able to bring it to life. Part of that is, of course, with Purina, and then part of that is also because of all of you continuing to share what topics you're interested in, what you're curious about. So this is, sadly, our last educational webinar of 2025. We have had so many, I think somewhere over 24 which is record breaking for us at Good Dog. But with that being said, we are planning for 2026 already, because it's going to be here right before we know it. We already have some things lined up for the beginning of 2026 but as we are continuing to plan, just keep sharing your thoughts with us on what you're interested in learning more about. Then you can email those to us anytime at breederteam@gooddog.com and we love to hear your thoughts and what you're looking forward to learning in the year ahead. And as I mentioned, this was such a record breaking year for us in terms of webinars that we've hosted. So in case this is your very first time joining us for any of these educational webinars, I want to just mention where you can find all of our past recordings, because we do record every single webinar we do, in case people want to re-watch them or share them; that's always encouraged as well. I think at this point, we're giving Netflix or Hulu a run for its money with how many things we have recorded in that library. So I encourage everyone to check it out. Hopefully everyone can find something that interests them there. All right, a couple of quick housekeeping things: of course, as with all of our webinars, we're going to prioritize some of the previously submitted questions first during the Q&A at the end, but please use the chat to ask questions throughout the presentation. We'll try to get to those as well. And in case there is anyone new here, like I mentioned, I just want to share a little bit about Good Dog and who we are for anyone who's joining us for the very first time. Good Dog is on a mission to build a better world for our dogs and the people who love them by advocating for breeders like yourselves, educating the public and promoting canine health and responsible dog ownership through events just like this. We're a community that is created just for dog breeders to run all aspects of their program from start to finish—everything from getting your new litter of puppies listed, meeting buyers from across the country, getting payments securely for those puppies, and kind of all the smaller things that happen in between a litter of puppies being born and going off to their new homes. We are here to support breeders throughout all steps of that journey, to really just give you much needed time back to spend a little less time doing some administrative things and running your program, marketing your program, so you can just spend time doing what you do best, which is raising your puppies. So if you are interested in learning more about our community, we would love to have you join us if you're not yet a Good Breeder already, and you can learn more at GoodDog.com/join. You can also just reach out to us anytime with questions at breederteam@gooddog.com. And I think last thing from me is I just want to formally introduce our speaker, Dr. Trumble, and share a little bit about his background before I pass things over to him for the presentation. Dr. Trumble received a veterinary degree from Auburn University College of Veterinary Medicine in 2022. He worked at a small animal practice in the Tampa Bay, Florida, area from 2022 to 2024 providing general practice and reproduction services. Currently, Dr. Trumble is a theriogenology resident (I always stumble over that word) at the Ohio State University College of Veterinary Medicine. He expects to receive specialty certification in theriogenology in July 2026, so coming up very soon. So Dr. Trumble, with that, I will pass things over to you to get the presentation started. 

Dr. Joshua Trumble, DVM  04:52

Well, hello everybody. Thank you for the warm welcome, Nicole, and thank you everybody for joining today. We're going to be talking about TCI and what we—as the veterinary community, in theriogenology as a whole—what we've been able to learn about TCI in the past years. So a couple of housekeeping things and table of contents we're going to talk about is: we're going to talk about the history of transcervical insemination; going to briefly touch on surgicals, some pros and cons; what we can evaluate while we're doing the TCI. I wonder if a couple of you have been able to see those and look at the things that we're looking at, but just to go over, what are we actually able to do during that TCI, and then we're going to chat about this study that the Ohio State did a couple of years ago, and what we're finding out from that. 

So starting all the way back in about 1322, is the earliest artificial insemination that I could find. That was done in horses. The story that I found was that was two rival tribes in the Middle East. Stolen semen from a stallion was used to inseminate a rival tribe's mayor. Well, all the way up until the 1780s, about 1784, there was the first successful canine artificial vaginal insemination done that did actually produce a pregnancy. And then we have our referred first reports of successful pregnancy from frozen semen back in 1969. Where we first recognized frozen semen bred dogs was in 1981. 

A couple of techniques to chat about with transcervical insemination. One of our first techniques was the Norwegian catheter system. There is this metal rod that is passed through the vagina, and then blindly, the veterinarian would palpate that cervix and be able to pass that rod actually into the cervix, as we can see down in this bottom image. This was first reported in about the 1960s. However, it wasn't really commonly done in the US, just because of a very high skill ceiling to do that. So most of our artificial inseminations prior to this was just vaginal AIs. And then about in the 1980s is when we started using frozen semen breedings purely by surgical inseminations. And we'll talk about some pros and cons a little bit later in the presentation. 

So another technique that came out, which is the one that we're currently using today: 1973, we have our first report of endoscopic trans cervical insemination into a dog. This device right here is a Storz uretero-renoscope, so looking at the ureters and kidneys of humans, or just parts of the upper urinary tract. That's what it was historically used for, but we were able to adapt it to canine models, and since then, the technique and equipment available has evolved to having dedicated vaginoscopes and hysteroscopes for devices to look in the vagina or into the uterus of the dog, respectively. 

So some of our tools that we now have available to our reproductive veterinarians. Two of our major TCI scope producers nowadays are Storz and Minitube. Storz was historically a uretero-renoscope, as we said earlier, but now has been redesigned to be used for both veterinary vaginoscopy and hysteroscopy, or again, looking at the vagina and the uterus of the dog. And then Minitube recently came out with their own device that is purely designed for use in vaginoscopy in dogs. Another tool that we use during TCI, commonly, is called a vaginal shunt. That is thought to both mimic the tie by applying pressure, either with filling a balloon with saline or just with room air, to apply pressure to the vagina of the dog, and it assists with visualization during the procedure, just so that we can see what we're doing. 

So we'll talk first about why I don't like surgicals, and then I'll go into a couple of pros of actually doing surgicals. Because we have the TCI now, I can minimize a lot of these risks that are here with surgicals. Anesthesia is the number one risk, in my opinion, doing surgical inseminations. All dogs that go under anesthesia do have the risk of the unfortunate anesthetic death, even in procedures like surgical AI, spay, neuter, what have you. Some of those major risks are aspiration pneumonia or inhaling material from the stomach into the lungs, or incisional issues, like the dehiscence, where the wound opens, or incision infections. With TCI, I can put the semen in the exact same place that it would go in a surgical. Once I get it past the cervix, it is going into the uterus. So, in this same location, right here, in this Y shape is the uterus right here in the dog. And then, as we've gotten better with TCIs, we've actually been able to get better conception rates than with surgicals. It's about overall, with all things being perfect, about 90 to 95% conception rate with TCI, where surgicals are in the ballpark of 80 to 85%. 

But there are good places for a surgical insemination. I will not say that there are not good places. Frozen semen absolutely must be placed in the uterus, so when I have TCI, if I can't get past a cervix in the very rare occasion (and we'll talk about that with the OSU study), then that semen has to go into the uterus, and it has to go in by a surgical or in the off chance you're working with a veterinarian who does not have access to a TCI scope. They're pretty pricey machines, so it's understandable. That would be the only other place where I would say a surgical AI must be performed. For fresh and chilled semen, I don't feel like a surgical is valuable to you, knowing the risks, just because that semen is going to live longer and it's much more capable of swimming up to the oviduct to actually be able to breed those eggs. But we won't talk too much further about surgical AI, just because the study that we're going to be looking at didn't really use it in any of their breedings. 

So the study that we're talking about today is factors affecting pregnancy success in the bitch following transcervical insemination. This is a free access study. You should be able to Google this and get it off of pubmed's free service, was written by Matt Cochran et al in 2023. Our OSU investigators were looking at several factors to see what was part of an AI plan that could affect pregnancy rates. So all the things they looked at was type of semen, whether you used fresh, cooled, or frozen semen; whether sedation needed to be administered; whether there was a difference between veterinarians, to the faculty theoriogenologist, whether there was any difference there. Or the biggest difference that hasn't really been studied is our number of inseminations right here. So that hasn't been looked at a whole lot. So to talk about some previous studies, “Artificial insemination in dogs, a retrospective study in 10 years using non surgical approach”—this was written by Thomas and colleagues in 2006. This previous study primarily investigated frozen semen only. So they unfortunately were not able to look at fresh and chilled semen, so this new study is reviewing breeding records from all types of semen. 

So let's talk about some breeding management before we go into that, just so that everybody's on the same page. Initially, all of the bitches that were seen at the Ohio State were seen about five to seven days after their owners first noticed vaginal discharge. A vaginal cytology was performed to confirm that all of these bitches were in estrus. A Brucella test was performed just for screening of disease, as well as progesterone timing was the primary mode of planning these breeding managements. Usually they were done every two or three days until ovulation was confirmed in these dogs. Let's talk about progesterone real quick. I'm sure all of you are familiar with this, but in case you are not, progesterone is an estimate of where a bitch is in her cycle. And I really want to stress that word estimate. I can estimate whether she is around her LH window, her ovulation, or actually in her breathing window. And there's multiple machines available with multiple scales for what numbers mean. So for simplicity, all of the numbers for this study, we're using the Immulite or IDEXX numbers, if you all are familiar with those. Those numbers are whether they were baseline (so progesterone was less than two nanograms per ml) around their LH surge, which is about two nanograms per ml, and then whether they were starting in their ovulation window, or they were completely ovulated. Ovulation window floats somewhere between a four to a 10, narrowing it down a little bit, can be four to a seven, maybe. Again, it's a guess. Sometimes I can be a little more confident if we're noticing a change in three units within a 24 hour period, but I can be fairly confident that she's completely ovulated if that number is greater than 10 nanograms per ml. So let's talk about LH testing, because several of the dogs in this study did use LH testing for frozen semen breedings. So LH, as we're seeing in this graph, it'll stay fairly low, fairly low, until, literally about 24 hour period, where it goes rapidly high and then it goes way back. Down again shortly before ovulation. So there's no commercial quantitative test available, so most veterinarians will use the witness LH test, which is an ELISA. Basically, we put serum onto a test strip, allow it to drag over that entire test strip, and then we'll notice a color change on that test trip to tell us if, yes, she has high LH in her blood, or no, she doesn't that day. It's the best thing that I can do to predict a breeding, but it's very inconvenient. It requires daily visits. The very longest time between visits would be 24 hours. My high score, unfortunately, it's 15 visits in a row, so it's really a commitment for you guys. 

Moving on. Our insemination timing was based on estimated LH surge or witness LH test. Again, that LH search happens at about two nanograms per ml. For all of these numbers, these are days post LH surge or estimated LH surge for all of these breedings. So for a single breeding or a cooled breeding, those single breedings with fresh or cooled semen, those were done between four and five days after LH surge was estimated. And for frozen semen, those were done either five to six days afterwards. But looking at a two-breeding plan, just because of the coordination between the stud dog and coordination with shipping facilities, fresh semen was done somewhere between three and five days for the first one and four and six days for the second breeding, giving the dog at least 24 hours between collections. Cooled was done somewhere between three and six days, with 24 to 48 hours apart. Again, to give the dog a chance to rebuild his sperm reservoirs and then frozen semen breedings (just because we like to do those as late as possible) were done at day five and day six post LH surge. 

Talking about some of the things that the investigators at OSU used: so they looked at fresh, cooled, and frozen semen. Every one of them was analyzed during the process of insemination. Fresh semen was collected on site and then analyzed using computer aided sperm analysis or CASA to help us look at motility, help us look at concentration and the amount of sperm we're using for this insemination. If it was a large volume, it was spun down to less than two milliliters using centrifugation prior to insemination. Cooled semen was received and looked at by CASA just to make sure it was still alive, not having any major concerns, did still have sperm in it using that same CASA tool. And if it was a large volume, again, it was centrifuged down to two mls or less prior to that insemination. And then frozen semen: that was thawed at 37 degrees Celsius for 30 seconds, which is usually the standard, unless it was otherwise specified by this shipping clinic. That's the temperature that it was thawed at. It was looked at on CASA after insemination, just because once I get that thawed, I want to get it in the uterus as quickly as possible. And for frozen semen, we used a desired dose of 100 to 200 million progressively modal sperm for that insemination dose. 

Now let's talk about the AI procedure. TCIs were performed with the Minitube vaginal scope. Got a picture of it right here on the right. Those breedings were performed either in standing or with the bitch laying down on her stomach or in ventral position. If you all are familiar with the veterinary terms, a vaginal shunt was used for all of these to, again, mimic the tie and assist with insufflation or inflating the vagina with air, to help with looking at the vagina and cervix on the scope. And then during the insemination, they were monitoring for backflow by directly visualizing that insemination. 

I figured we would want to look at what we're seeing when we're performing your TCIs, just because it can look like a whole mush of pink. And I totally understand that. That's what it looked like when I first started looking at these. So first thing that we're going to look at is the vaginal canal. That's what we're seeing all over here on this image on the right. So this is very important in identifying that we're inseminating it at an appropriate time. What I really want to see in this vaginal canal is all of these little peaks and troughs that we're seeing right here, and this bubble gum pink appearance of the vaginal canal that tells me that we're in the right period. If we're too early or too late, it can look very pale or lose these crenulations. So that may cause me to have some concerns. And sometimes we can find foreign material in the vagina. There's been several times where I've found, like, a grass frond during a TCI. Usually she'll pass those when she whelps out, unless it's causing some amount of irritation to the vagina. I don't make a fuss out of trying to fight to pull that thing out, just because I don't want to cause more inflammation than I already am by doing it and an insemination. 

So one of the next things that we'll see is this structure right here. This is the dorsal median fold. Tells me we're getting really close to where we're trying to go, to identify the cervix. And then next thing is this little protrusion below it, that is the cervical tubercle. Or some veterinarians will call that the pseudo cervix. This is not the opening to the cervix or the OS, as medical terms will tell us. You have to keep going and actually go under this structure right here, to actually get to the OS of the cervix. And now we've made it. So all of this right here is the cervical OS in the normal bitch. It's actually downward facing. So if my fist right here is the opening to the cervix, it's actually facing downward on that vaginal canal and basically sitting on the bottom of the canal in this position. So what I have to do is I have to actually use the scope to elevate the cervix and then pass the catheter directly into this tiny little opening right here, is the opening to her cervix. I don't have anything else that I can use to manipulate it. I don't want to use anything else either, because the cervix is super easy to injure. It's not made with the same tissue as our outside skin is made of. It's made of a much more friable tissue. So I want to minimize the manipulation to the cervix as much as possible, because I don't want to cause any more inflammation that I'm already going to cause by breeding this dog. So what I need to do is I need to rotate that cervix and pass a catheter into this opening. It's a lot easier to say. It can be very challenging to do, but veterinarians have gotten very good, and usually we can get them eight out of 10 times within just a minute or two.

And then success! So what we see right here, this is a different dog. This is her cervical opening between this entire image, and up here, this black and white structure is actually the catheter that is going into the cervix. We'll pass that a few centimeters past the OS to ensure that we're in the uterus. Some scopes, like the Storz hysteroscope, actually can be passed into the uterus, but it usually is not during a breeding, just because, again, that uterus is very easily damaged. And since I'm putting semen and we're hopefully about to put puppies into that uterus, I really don't want to cause any damage there. And then, as we're doing that insemination, we'll notice these little air bubbles that we're able to see during that breathing, that is just gas escaping the uterus. What I'm doing during this breeding is I'm putting the air into the bitch’s vagina so that I can actually see what I'm doing, so I can visualize the cervix. But because the cervix is open, it's going to go straight into the uterus too. So I'm basically displacing this gas with semen, and what's escaping now is the same discharge that would be coming out vaginally just from being in heat, as well as these little bubbles that are created just from the air. I can actually tell the difference from the semen from these gas bubbles, if I'm seeing that semen has come out, or what's called retrograde flow, I can pause, adjust the rate of my insemination just to make sure that the maximum amount of those sperm are going into the uterus. Just because no sperm going into the uterus makes no babies. Okay? 

So let's talk about some abnormalities that we can see during that, though. This is called a persistent hymenal remnant. So this structure right here . . . let me see if I can change the color just to make that a little bit more visible. So this structure right here is part of this dog's hymen, or basically one of the remnant structures from when her outside vagina was meeting her inside vagina. They make a little closure right here. And once she goes into puberty, this should break down all the way until she has a complete vaginal opening. Some dogs—and I don't think we really have a great way of predicting—don't break it down. They'll usually leave this ligament right here that's not really known of until the time of breeding. And probably what may have happened to cause some infertility is, you've tried a natural breeding, and she absolutely will not allow it. The male partially penetrates and then she says, “Absolutely not. This is not going to happen.” So during that procedure, we can either try and stretch this structure, or we can make an adjustment to our whelping plan as there is a possibility (unlikely), as once she starts pushing puppies out, this ligament should break down completely, but there is a risk that she may need a C-section with this breeding. But not future breedings, just because once this is gone, it's gone for good. 

Another abnormality that may happen this one is much, much, much more exceedingly rare, but I've seen a couple of them, so I wanted to bring it to your attention: cervical lacerations. So this up here that I'm highlighting in the upper two thirds of the image is a cervix from a different bitch, and then down here, not sure if you're able to notice, but this dark spot is actually a separate opening into her uterus. So during this TCI, we were going into inseminate and notice this opening, and explored it. And actually it was all the way into her uterus. And this is another thing that, unfortunately, I have no way of knowing of, and you guys will have no way of knowing of, until we actually go to do the insemination, that there was some damage to the cervix. This is very, very more likely to be as a result of dystocia, rather than some breeding trauma that happened with a previous breeding that resulted in an infertile breeding. Unfortunately, these dogs with these cervical lacerations, there's nothing I can do to put the cervix back together. So there's very, very poor prognosis for future fertility for these dogs, and even if I did actually perform the insemination and breed this dog, there's an open communication with the non sterile vagina, with the uterus, where those puppies should be gestating. So unfortunately, usually these dogs are permanently infertile. But again, I want to stress again, this is exceedingly rare. I've only seen two of these in four years of practice. So I wouldn't make this a major concern for you guys. So we'll talk about the sedation that was used. Sedation was only used as needed for these bitches, either they were extremely anxious, nervous or fractious, and there were two major sedation protocols used. Either they were given an Alpha-2 agonist called dexmedetomidine, which I would just classify as a mild sedation, or that dexmedetomidine was given in conjunction with an opioid called butorphanol, and then I'll classify that as moderate to heavy sedation, just for simplicity, okay?

For pregnancy diagnosis, that was either done via ultrasound at four weeks after the artificial insemination or with abdominal radiographs one week prior to the due date. These were done via however the owner elected to do them. On this ultrasound, we can see one little embryonic vesicle, and we can actually see the fetus right here. So we have a little puppy. Don't remember how many pups this dog had.

So let's talk about some results of this study. They included 267 bitches that were bred at the Ohio State during this study. Overall, across one and two breeding sedated, not sedated, everything, they had conception rates of about 77% with fresh semen, 67% with cooled semen, and 71% with frozen semen. They did find that there's no significant difference between which veterinarian performed at the TCI as long as they were experienced with the procedure. And then these numbers that we have up here, I'm looking back at previous studies. They were similar to previous pregnancy rates from TCI. 

So what did they learn from the effect of sedation? There was no significant effect of sedation overall on pregnancy rate. It was a little bit lower. However, that could just be a statistical error, so we can't really say it's truly lower. The mildly sedated dogs were also numerically higher pregnancy rate compared to heavily sedated dogs, and we'll try to talk about a couple of reasons, potentially why a little bit later. And then overall, actually, catheterizing the cervix was more difficult in sedated bitches. So the bitches that received heavier sedation plans were often highly anxious and fearful due to high cortisol or stress for a few of them. There was some amount of veterinary visit anxiety that was going on for these dogs. Mild sedation does not cause a decrease in pregnancy rates compared to the unsedated dogs, but this study doesn't actually look at “Does sedating all dogs” or “Does sedating dogs that only need sedation” . . . that's not what the goal of this study was. They were only looking at “Do anxious dogs that get sedated have changes in pregnancy rates?” And I feel like that's a more fair thing to say, is that the anxious dogs have a worse pregnancy rate. But just to talk about some numbers, comparing sedated to unsedated, 85% of catheterizations were noted as easy, where 50% were noted as easy in sedated patients, and then only 3% of catheterizations were unsuccessful in unsedated patients. So yet another reason why I don't believe surgicals do you much benefit anymore. And then down in sedated patients, unfortunately, they weren't able to get up to 20% unsuccessful in sedated patients. The remainder of these numbers will compromise medium and more difficult. But overall, sedated patients were more difficult to catheterize. But based on how we've continued using the marker for catheterization at OSU, I can't say that difficult catheterization is just because of the sedation. Again, that wasn't tested as a model alone for these dogs in this study, or any previous study. We'd actually need to do a study on “Does sedating a dog actually make the catheterization more difficult?” Patient handling difficulties at the OSU were incorporated into these difficulties catheterizing the patient. So I feel a lot more of these dogs were difficult purely because they were difficult to handle weekly or uncomfortable or just anxious about being at the vet. Sedation was only used to help facilitate difficult catheterizations in bitches here.

So let's talk about types of semen used from these dogs. The fresh semen, as we would expect, produced the largest litters on average. The group of dogs was not separated into small, medium, large, and giant. So on average, fresh semen produced seven puppies; chilled, five; frozen, about four and a half. There was no significant difference between semen type in overall pregnancy ratings, just some small numerical differences. So number of inseminations overall, we can expect an 8% increase in pregnancy rates. Breaking it down a little bit more: fresh semen, there was barely any difference. There was about a 3% increase numerically with fresh semen. Chilled semen in this study was actually where there was the most significant increase. They saw about a 13% increase in the pregnancy rate with this study. With frozen semen, they actually noticed that there was no significant difference, but it was mildly numerically lower when you did two inseminations, but with frozen semen, what they did find is there was an increase in litter size by about a puppy. 

So, a couple of takeaways as we finish our time together. This study that OSU did—it confirms what we already know. Progesterone timing is one of the most important things that you can do with your veterinarian when you're doing artificial insemination, and LH testing in conjunction with that progesterone timing—all the more makes this breeding management better. We know that fresh semen is better than chilled semen is better than frozen semen, and we know what matters the most is the amount of sperm that we're putting in. What we can infer from this study is that stressed bitches may have reduced fertility overall, if they have veterinary visit anxiety, they're going to have ups and downs and ups and downs in their cortisol in their body, or the stress hormone, so that may have an effect on their ovulation cascade, as we've learned from other species, like cows, but there's little that we can really do to de-stress these dogs. We learned that the number of inseminations can be valuable. With fresh semen, a single good quality semen should be sufficient for our breeding. With chilled and frozen semen, two inseminations may be useful. Chilled semen, we get about a 10 to 15% increase, as well as an increase in about a puppy. And then some things that we've confirmed from other studies is frozen semen is significantly better when we're using more semen. Another study found that two full breeding doses significantly increased the pregnancy rate and litter size for frozen semen compared to a single breeding dose. And then the last thing that we can take away is cervical catheterization was similar to other research. About 80% were marked as easily done. This study did have some limitations where it didn't remark for cervical catheterization on previous parity. We know that the cervix relaxes when they've had puppies before, so it does cause some laxity for future catheterization. So we can't say for sure if it's difficult just because she's a maiden bitch, and then it's important to minimize manipulation of that cervix just to reduce inflammation. So as we wrap up, I want to say some thank yous. I want to say thank you to AKC and Canine Health Foundation and Therio Foundation for sponsoring my residency. I want to thank Good Dog and Purina for allowing me to speak for you guys. And I want to thank you for your attention. 

Nicole Engelman  35:35

Amazing! Thank you so much, Dr. Trumble. Is it okay if we go through a few questions that have come in? Well, just a few quick ones, actually, before we get into some of the more in depth ones that we received over the past few weeks from breeders, and we just have a few questions about the procedure itself. So one of them is just clarifying if the bitch is under anesthesia for all of this, and do they get antibiotics after the procedure?

Dr. Joshua Trumble, DVM  36:03

So we'll start with part one. Usually bitches are. For TCIs, the vast majority of them can be done with no anesthetics or analgesics. Usually, they're standing and either getting treats from the owners or tolerating it without any additional handling other than just being held and getting attention from the owners. And then antibiotics, that's a bit of a controversial thing still. There's a lot of mixed opinions on using antibiotics at time of insemination and during breeding in general. So I won't say one party is correct or incorrect. What we do know is that antibiotics will cause some dysbiosis or some changes in the normal bacteria of the vagina, potentially increasing her risk of UTIs. And we try to avoid antibiotics wherever possible, just because every antibiotic that we dispense increases our risk of antibiotic resistance. So me, personally, I don't use antibiotics at time of breeding or a TCI, unless we have a documented issue, like we have done a uterine culture where she's growing gross things in her uterus, or she has a concurrent UTI, things like that. Does that make sense?

Nicole Engelman  37:19

Yeah. Awesome. And just a quick follow up to what you mentioned about anesthesia, we have another question about maybe some pre-anxiety medication to give any bitches that might be nervous before they arrive to a veterinarian's office. Anything you recommend there to kind of quell some anxious nerves?

Dr. Joshua Trumble, DVM  37:38

That’s the hard part right now, just because a lot of the medications that we have haven't been tested in breeding dogs, haven't been tested in dogs intended to become pregnant, or during actual breeding. So I try to err on caution away from prescription meds. Using homeopaths I think are great, calming supplements. I think there is a future for things like CBD. I've used it for pets, but again, not for dogs that are actively breeding. So I don't know. I think that's an area that we need to figure out what we can use, just because there are some concerns that it could have an effect on our fertility rates. Everything causes changes in the uterus just because it's the first thing to go. So I don't want to add on any true anesthetics or sedations unless I absolutely have to.

Nicole Engelman  38:29

Awesome. That's really helpful. The next few questions we have are a lot about success rates, which I know is top of mind for breeders when doing anything like this. So one question is asking: what sperm counts, motility, etc. do you recommend as the minimal requirement for a successful TCI procedure? And do those results change from time of freezing and/or upon thawing before the TCI?

Dr. Joshua Trumble, DVM  38:56

So we will stick to frozen semen since that sounds like what your question is. So frozen semen, we do have good studies saying, depending on size of dog, somewhere between 100 to 250 million progressively modal and morphologically normal sperm is adequate for a breeding dose. Now, the problem with that right now is that advice has changed from what we've been historically using in the past 10 years. So if you have older frozen semen, that's where we're currently getting the recommendation of “We want to have two breeding doses available to us, just in case we need to thaw the second one, because we're not getting up to that mark.” Let's say I have Great Danes right now. We're not getting up to that 250 million progressively modal, morphologically normal sperm to get us a really solid breeding dose. Does that answer their question totally?

Nicole Engelman  39:54

I think so, and it kind of leads us nicely into the next one, because I know you mentioned depending on the size of the dog, I know that it's a big factor. So we did have a question specifically about that: is there an advantage to surgical versus TCI, particularly for larger breeds?

Dr. Joshua Trumble, DVM  40:09

I don't feel that there is a true advantage anymore, just because of the anesthetic risks of surgical insemination with large breed dogs, especially with cardiac concerns always being a major concern for large and giant breed dogs. I don't feel like there is a super big benefit anymore with surgicals outside of those two scenarios, which I said earlier, where either you're in an area where you don't have access to TCI, or you're doing the right thing. Your veterinarian is attempting TCI, but your bitch unfortunately falls into that 3% category where we're trying and trying and trying and we can't get through that cervix, and we're using frozen semen, which I feel like is a very limited group of dogs. In my past, I'd say about 500–600 bitches that I've done breeding management for I've only ever not been able to get through the cervix on this many of them.

Nicole Engelman  41:10

Awesome. Thank you for answering that one. Now we have some about considering one or two TCIs, so the question was: when using frozen semen for TCI, what is the minimum amount of progressively live semen that you recommend for an insemination? And if you have more than that available, are you better off doing more than one TCI? Or can you use double the dose on one TCI? If so, what are the optimum days for either one or two TCIs? So I know that was a bit of a mouthful question.

Dr. Joshua Trumble, DVM  41:41

There's a lot to unpack in there, so I'll try to answer the whole thing for you. So the advantage of doing one TCI with two doses or two TCIs with a single dose each, I think, is the first part of that question, with us not having a major difference between one and two TCIs right now, with the information that we currently have, I think it's the breeder's choice, whether you want to split it between two breedings or just do the single breeding. With the two breedings, we did notice an increase in litter size by a single puppy. So I think that is something that is worthwhile to talk about, as well as with frozen semen only being alive for about 12–18 hours max, there's a good thought to actually spreading out that dose to make sure that we have sperm ready and waiting for all of the eggs to be fertilized. Since we noticed an increase in litter size, I think that is something that is worthwhile. With the way I practice, it is purely up to you, whether you want to do that two breedings or single breedings. We'll talk about the pros and cons, and then it's up to you. With it not having an increase in pregnancy rates, I don't think it's something that I'm going to push for you to do two breedings at this point, if that makes sense. The more important thing, in my opinion, for a frozen breeding is that LH testing. Progesterone is only an estimation of the LH window of ovulation, of our ideal breeding window. With LH, when it is positive, I am breeding your bitch five or six days after LH, regardless of her progesterone unless it starts doing really, really weird things.

Nicole Engelman  43:24

It was very complicated question, so I appreciate that. I think we have time for one more, which I think feeds a little bit into what you just shared. So this is from a breeder who said that they are not able to run progesterone levels, but if someone is unable to kind of track that, and they only had one opportunity to perform a transcervical insemination, is there an exact stage of cytology that you would consider the most accurate indicator for best success? Is that just kind of an art and a science, and you can't really tell?

Dr. Joshua Trumble, DVM  43:58

This is where it gets into really artsy kinds of things, because we're having to make a whole lot of assumptions with this breeding, just because I don't know if she actually is progressing to LH, ovulation, things like that. What we can do to try to work around that is daily vaginal cytology. So what we know from vaginal cytology, looking at this slide, is this bitch is fully quantified. The only other option that we realistically have is doing daily vaginal cytologies and breeding on the day where she first loses cornification. So when they first start going into diestrus, they will drop their cornification (or basically these really sharp edges) very rapidly. I don't like breeding off of this alone, just because we're breeding at day one, when she's in diestrus, or when she's no longer anestrus, there's an increase in risk of developing pyometra from breeding this way. Another avenue that I think would be better to go on would just be collecting blood samples for LH testing and testing those but the cost of that is probably going to be a whole lot more than doing these vaginal cytologies. So that's something that you'd need to be aware of. 

Nicole Engelman  45:20

Awesome. I think that was the last question we had, but thank you so much for answering those. I know they were pretty detailed. And thank you to our community for asking such amazing questions. They were great. Dr. Trumble, thank you so much for hosting this presentation. I'm seeing some praise in the chat about how great this was. So we're so happy to have you here, and hopefully this is a topic we can cover in the future, because it sounds like we're kind of just scratching the surface here on what our community is curious about.

Dr. Joshua Trumble, DVM  45:47

Awesome. Thank you for having me, everyone. It was wonderful chatting with you all.

Nicole Engelman  45:50

Of course. Amazing. And thank you to our community for joining us today. As I mentioned, this is our last webinar of 2025 but we have so much coming up in 2026, so stay tuned for that. But until then, I hope everyone has a wonderful rest of the day. Thanks everyone. Bye.