Thank you to everyone joining us for our members webinar this evening. Tonight we have Doctor Brendan Tyndall who will be presenting on contraception in African elephants. Doctor Brendan qualified from the University of Pretoria in 1999, having completed a BSC degree in zoology, followed by a BBSC degree in veterinary science.

Shortly after graduation, he was appointed as a wildlife veterinarian for a national park in Namibia, where he was based in Etosha National Park for a few years. Here he gained enormous experience in working with black rhinos as well. As supervising routine mass capture operations of wildlife.

After returning to South Africa, he continued practising as a wildlife veterinarian in private practise. During his 22 years in practise, he has gained extensive experience in working with a wide range of wildlife species. Brendan has a special interest in research and conservation, and it's currently working as part of an international team developing techniques.

Increo preservation and assisted reproduction of rhinos. In addition to his wildlife veterinary practise, he also owns a mixed animal practise where he enjoys small animal orthopaedic surgery as well as routine equine veterinary practise. Brandon also serves as a counsellor on the South African Veterinary Council and was recently appointed vice president of the SABC.

If you have any questions during the presentation, please use the Q&A box and at the end, Doctor Brandon will answer your questions. Thank you so much, Doctor Brandon for being here with us tonight. Thank you, Theo.

Yeah, it's a, it's a privilege for me to be here. Thank you for inviting me. And, yeah, I hope my colleagues out there will, enjoy listening to, yeah, some of the, information I have with regards to the work I do.

And, this time, particularly on elephants. And, yeah, I look forward to, to sharing this. It's, it's the type of work that we as wildlife veterinarians in South Africa do.

And, but it's a lot of this information, might be very useful for, you know, for, for zoo veterinarians as well around the world, especially with regards to the management of of elephant in, in captive environments. So, I think a lot of this information and, and knowledge, may be applicable for, for many of those veterinarians that are involved in, in zoo environments around the world. And yeah, so thank you once again and I'll, I'll start with my, with my presentation.

So I'm going to be talking really on, on contraception and, and population management in free-ranging African elephant. And what I'm going to do is I'm going to start by just giving you a little synopsis of the wildlife, industry, in Southern Africa. And then I'm going to run through a couple of the contraceptive, techniques or, vaccination protocols that we do have available to us and that assist us in, in managing elephant populations.

And, and then I'm going to also then just finish off by giving you, just a, a very brief, summary of, of how I approach, you know, contraception and elephant management and how I integrate the two different forms of vaccination protocols that we have, from a management point of view. So I'm going to start first of all, just by running through what the current wildlife synopsis is in Southern Africa. Ecotourism in Southern Africa is obviously a very important part of, the regional economy.

And, so we have, in addition to having our big national parks, we also have a lot of, area that's, privately owned, that's dedicated to conservation initiatives. And so the animals that exist on these reserves are are privately owned, and they're owned by the, by the individuals. And most of these reserves are relatively small.

I think in terms of what a lot of the, the rest of the world is like, they may seem quite big. I mean, but most of the reserves are in the region of about 20,000 hectares or, or just a bit smaller than 20,000 hectares, which is in, in acre terms. I think that's approximately about 40,000 acres.

So they, they, in, in African, from an African perspective, that's, that's relatively small. But I think from a global perspective, you know, 20,000 hectares is a fair, fair piece of land and, and real estate. But this is the size that's really required to, to run and you know, and operate and manage a, a free range, wildlife reserve that, that can offer ecotourism safaris, etc.

These reserves are all fenced and, you know, the minute we put up a fence, that means that we need to manage the animals that, that live within that fence. And so, you know, that, that is very fundamental to the whole management of these reserves. The ecotourism.

Models that exist, allow these reserves to remain financially sustainable. So I think that's a very important concept to understand is that these reserves exist because they're financially sustainable. And we have to manage, You know, the wildlife and the conservation within these reserves, based on these business principles.

OK. So that's very important for us to take into consideration every single time. And, But, in addition to this, we obviously have very strict environmental management plans that we draw up and that that's a, these plans are drawn up as a collaborative effort between, conservation officials, as well as veterinarians, and then, of course, the owners as well.

And the idea is, that these management plans are there to protect the environmental biodiversity, which is, which is the key thing that we all look at. Although they are business models, ultimately, biodiversity and, environmental stability is what we're really after. And when we look at the whole team, that is in place, veterinarians play a really, really important role when it comes to decision making.

So, we are integral in this whole, team approach, whether it's, we, we're looking at big national parks that are state-owned or on the smaller reserves as well. So, veterinarians play an integral role in conservation. And, and, the term that I use to describe it is, conservation medicine.

So, we have the medical side, but, we also have the knowledge with regards to conservation as well. And when we put that all together, we, we classify it as, as conservation medicine. When we look at, at elephants in particular, obviously, they're one of the iconic African species.

And they are integral to sustainable wildlife conservation. In, in the small reserves, as I mentioned, they, they fenced and they, they, you know, approximately 20,000 hectares. Within these reserves, these elephants have no natural enemies.

And, if they're kind of left to their own devices, their population, increases very rapidly. And it often, or very shortly, it's, it's possible that they exceed the sustainable capacity of that reserve. And, Once that happens and if they're left uncontrolled, elephants are particularly destructive when it comes to vegetation.

And, they can have a significant effect on biodiversity and ultimately on, on tourism as well. So, that is something that we, we really need to take cognizance of. And that's where the whole concept of, you know, of population management and ultimately, you know, contraception in elephants is so important.

But the one other thing that we always need to take into consideration with elephants in, is that, An elephant herd, is at its most stable when it has a population structure that ranges from having, you know, dominant females, and then, all the way down through the sub-adults and then to having juveniles. Juveniles in the herd are really, really important for stability. Elephants have the most, wonderful nurturing, attributes.

And so they love to look after babies. And, and, you know, if their babies in the, in the herd, the herd is generally, much more content. And so, when we start to look at how we structure the contraceptive programmes and population management programmes with elephants, we always have to take into consideration, how do we do that, but still allow some form of, of, breeding to take place so that there are, there are calves coming through the system.

So these are all the things that we need to look at. And, keep in the back of our minds when we start to, you know, look at population management, particularly in elephants. It applies to many other species as well, but elephants in particular, because they're so destructive on the environment, it's, it becomes really, really important in these fenced-in reserves for us to, to manage elephant populations.

And I think, an important thing to understand with regards to, contraception as well, and, and the, and the things I'm going to be talking about, they Very much, aimed and structured around population control in relatively small herds of elephants. So, on these, on these small reserves, 20,000 hectare reserves, the, the population generally is somewhere between 40 and in some cases, up to 100 individuals. And that's a, that's a manageable size for us to implement a, a contraceptive or management programme.

Anything that's bigger than that becomes really tricky, and we have to look at other approaches. That, that we can utilise there. So the, the information and the ideas that I'm giving here really are, are aimed at and targeted at those populations that are free-range, populations.

And, and also, you know, potentially, captive elephants as well, cause a lot of the work was done on captive elephants. But, but mostly, small herds of between 40 and 100 that are in a confined area and that we can manage adequately. So this is a, a, just a, a broad overview of contraception in wildlife.

And, really, I've, I've included this just to show you, you know, the different options that we do have available. And they're really divided into three different categories. The first one is surgical.

And I'm gonna really stick to talking about elephants here. And, you know, naturally, you can, you can, understand that surgical contraception in, in elephants is, is very difficult. It's not to say that it's impossible.

So there has been some work done with regards to vasectomies in elephant bulls, using a laparoscopic technique, but it's, it's very, labour intensive. It's quite invasive. It's, it, it requires exceptional skills.

And so it's not something that can be routinely done in the field. But it, it is there, but it's not something that we would, you know, consider under normal circumstances for, for routine management and, and contraception in elephants. The second one is, is hormonal control.

We, we know that hormonal control, works. I think the, the, the one hormone that, is most commonly utilised and that people will be familiar with is the use of Deslorein. Which is a GRH implant.

OK. So it's a GRH agonist. And it's implanted into males or females.

And, that creates a negative feedback and therefore, it ultimately breaks down the reproductive cascade, the hormonal reproductive cascade. And it's, it's very effective in, in many different species. In elephants, unfortunately, it's, you know, it's not something that can easily be applied.

The animal needs to be immobilised every single time for that. The implants need to be inserted under the skin. So it's not a practical means of controlling elephants.

And then the final category is the immunological methods, OK? And here we look at, at, at vaccinations that are specifically designed to, to, we can call it chemical sterilisation of, of individuals. And, This is something that we utilise all the time in elephants, OK?

And there's, there are really two different products and two different techniques that we utilise here. And those are the two that I'm going to discuss in a little bit more detail. So we're really looking at, immunocontraception and, and how we can apply it in elephant population and contraception.

OK. All right. So, just a, a recap then.

So why elephant contraception? I mean, we talk about these things and, and, and people, you know, often ask, well, why is it necessary? Well, from what I've said just now, you can see that population overgrowth is a, is a major problem with these.

Reserves, there are no natural enemies. They're relatively small, fenced reserves, and they soon carry, you know, reach their carrying capacity. And if left un checked, then elephants, ultimately can have a devastating effect on the environments.

The other thing also is that within these relatively small areas, aggression, By elephant bulls towards each other and towards other species and humans, is also something that we have to take into consideration. As I mentioned, a lot of these reserves, are sustained by ecotourism. And, elephant bulls go through periods of increased sexual activity, and we call that, must.

And these elephants, bulls go into, into must, on a regular basis. So it's a, it's a fluctuating hormonal level. And they become, quite, aggressive potentially during these periods.

And during these times, they can often be very aggressive towards each other and also towards other species. On some reserves, we have quite a lot of aggression towards rhinoceros as well. And, that Potentially can be quite a big problem.

And then, of course, when we've got tourists also that are on safari vehicles, and we've got aggressive elephant bulls that potentially can also be something that we need to, need to avoid. So we can use our techniques to control this as well. OK.

So when we start to look at population management on a particular reserve, we have to understand that each reserve is unique. OK. So there's no single protocol that we can apply across the board to all these reserves.

We need to sit down and look at the, the individual reserves, and we need to tailor make or decide on a, a protocol for each reserve. And when we start looking at These protocols, and these considerations, we need to take, number one is we need to take into consideration the welfare of the elephant population. That's number one.

We really need to make sure that what we're doing is in the best interests of the elephants themselves. And those are the things where I said about looking at young calves coming through the system as well, allowing some females to, to be reproductively active. The, the other thing, the next thing, number 3, that we need to take into, into consideration is at the time since the reintroduction.

So, we, early on in the introduction, certainly from, from, the way I see it, the, and approach it, early on in the rep in the, shortly after reintroduction, particularly into a new reserve. So we will, You know, a lot of these reserves, when they established, don't have elephant populations present. And so we reintroduce new herds there.

And, once we start a management protocol, we, we need to take into consideration and you'll understand a little bit later why, what the time, frame was since reintroduction, cause that, that determines what protocol we might put into place. And then we need to look at what the current population size is, and what the target size is, what is the carrying capacity, and how are we going to, structure our protocols in order to achieve what our target size should be. And then, we also need to look at, are we going to target the males or are we going to target the females as our contraceptive, population.

And, that really boils down to what I was saying at point number 3. There is the time since reintroduction. Because that time since reintroduction is really what determines from my perspective, whether we start looking at male contraception initially or female contraception.

And, and they differ slightly. OK. So I said, I've mentioned to you that the technique we use is really based on immunocontraception.

So what, what is immunocontraception? OK. Immunocontraception is a non-hormonal form of contraception.

And the idea is that, immunocontraceptives stimulate the production of antibodies against some essential element of the reproductive process. And by doing this, this will prevent pregnancy from occurring. OK.

So advantage, well, vaccines carry some distinct advantages. OK. Vaccination is very easy, OK?

And it's non-invasive. Once we start to look at surgical, sterilisation, obviously, that becomes much more invasive, and it's certainly not as easy, OK? But vaccination, if effective, has very similar effects to, you know, for instance, a castration.

It's very simple to apply. We don't need to immobilise the animal at all. It really just requires an injection.

This can be done depending on the, on the circumstances. If it's a captive elephant, it can be done by hand. But for our purposes, mostly we doubt them, OK?

And yeah. So, this is much more preferable to the GNRH, as I said, in where the GNRH, implants need to be surgically, kind of implanted or, certainly when the animal is anaesthetized. So, you know, the vaccination is far more simple than that.

The important thing here also is that the vaccination has low biological risks. OK. It's not a hormonal treatment at all, OK?

And, therefore, it's not really expected to have any negative side effects whatsoever. It's also potentially reversible. So that's something that's quite important because our management objectives may change with time.

And if it's possible to reverse what we, implemented, then that might be, to our advantage. So, the nice thing about vaccination is that, most of these require annual boosters. And as a result of that, if we stop vaccinating them, if given sufficient time, most of these animals, revert back to being sexually active.

And, lastly, from an owner's perspective, obviously, this is a much more cost-effective method of sterilisation compared to, to other methods as well. So vaccination is really something that is very beneficial to us in managing these populations. OK.

The disadvantages of, of vaccination, obviously, that it does need to be repeated. The reversibility, is questionable under certain circumstances. I think that we've seen that animals that have been on contraceptive programmes for an extended period of time, some of them struggle to return back to normal reproductive activity, and some of them don't return at Or.

So that potentially can be a problem. As I said, most of the cases, we can, they do revert back to, to some form of reproductive activity, but there are cases where, where they don't. So that potentially can be a disadvantage.

We do have individual variability, as with any, vaccination protocol, whether it's in humans or whether it's in other species as well. Individuals react differently and that's something that's out of our hands, but potentially can be a disadvantage for us as well. One of the other things that really needs to be brought across to, to many of the owners is that, vaccine or immunocontraception doesn't have immediate effect.

You know, we generally start to see the effects from about 2 to 10 months post starting the treatment. So, particularly when we have aggressive animals and things like that, where we want to have some form of intervention, the quicker the better, but we do need to advise people that, you know, it's not an immediate effect. It does take a little bit of time to You know, for the, the effect of the vaccination to, to really kick in.

And then, we always need to take into consideration what the, the risk is to humans with, you know, certainly the, the, the people working with these, with these vaccines. Accidental injection potentially also can be quite harmful to humans. And, if, they can exert their Effects on elephants, they're going to have very similar effects, on accidental injection in humans as well.

So we always need to work quite carefully. As we do with most drugs, in the wildlife industry because they are, are potent. We do take extra precautions, working very carefully, but it's something that we just need to take into consideration all the time.

Right. So the two methods of immunocontraception in elephants, are, the poor sign Zonopelucida vaccination. OK.

This is specifically for females, right? And the second one is the GNRH vaccination. This, can be used on females as well, but we essentially, in, in, elephant terms, we really, really kind of restrict that to the use in males.

And, what I'm going to do is I'm gonna run through these, two, types of, or these two various types of, of, immunocontraception. And, and just give you, you know, a brief summary of, of how they work. The, the hoa zona.

That a vaccination or vaccine was developed by a professor from South Africa from the University of Pretoria in collaboration with, with an international team as well. Professor Hank Berzinger was the, was the leader of the team. And, the publications came out in about 2008.

And so they, they started and they were the ones that were, that developed the PZP. We, we refer to it as the PZP. So when I talk about the PZP, I'm talking about the 4 sign zona Peluc the vaccination.

And, then the second one, the GNRH vaccination of males. Look, this, this, the, the concept, was developed obviously in domestic animals, particularly in pigs. The, this was used or still is used extensively in the chemical sterilisation of pigs.

And, and this has been extrapolated, to use in other wildlife species or in, in, in the wildlife industry. And, I was part of a, international team here in, in South Africa where we looked at the use of GNRH for, vaccinating males. And our objective on this was really to look at, you know, how do we control behaviour.

Our, our, our, you know, original objective was looking at captive elephants and making sure that we can manage. Captive bulls adequately that they don't pose a threat to themselves or to a threat to, to other elephants and people in a captive environment. And so that's where our original protocol stemmed from.

But subsequent to that, obviously, it's been really effective and we can use it for, for other management tools as well, such as contraception and management and population management. So, first of all, just, The Paine zona Pellucida vaccine, OK. It's, it's a vaccine vaccine.

Here, you can see, this picture just shows us, you know, darting from a helicopter. So most of this work does get done from a helicopter. We can't approach all of these.

Ryan, these elephant from, from the ground. So we need to, to access them by helicopter. And, so this is a, this is a typical type of operation.

And I'll show you just a short video just now of, of what it really looks like. It's quite a, a An intense process, but it's, it's very quick. And although the animals are, are disturbed for a very short period of time, it's very effective and it doesn't take us long.

We can do a herd of 20 to 40 elephants in the space in less than 10 minutes. All right. Really, I'm going to just briefly explain how it works.

This picture was taken from that publication by, of, Prof, Birchinger. And what it, what it really describes is how this Zonopaluccida or PZP vaccine works. Under normal circums what we circumstances, we have an oocyte, that's released into the fallopian tube after ovulation.

And, this ocyte is surrounded by a capsular layer called the zona elucidda. And, the zonopeluccida has multiple, receptor sites on it that, they are binding sites for sperm. And the sperm have to bind to it.

And they go through a process, they call it an arosome reaction. And, this allows the sperm then obviously to penetrate through the zonopelucidda. And once it's through the zonopeluccida, it's then able to fertilise the egg inside.

Now, what the PZP vaccine does, the PZP vaccine was a vaccine that, as, as the name suggests, it's been, produced. Through the harvesting of the zona pellucida from pigs, that are destined to be slaughtered or have been slaughtered, in abattoirs. And, so what this PZP does is it stimulates the body to start producing antibodies against the PZP layer or this capsule.

And what it does is those antibodies then attach all the way around to all the receptor sites on the, PZP capsule. And by doing that, they then prevent the, sperm from binding. And obviously, that, then prevents pregnancy taking place.

So, what are the advantages of, of PZP? OK. It's a very effective means of, of, of contraception, of sterilisation.

It's at least 90% effective. So that's, that's something that's very beneficial for us. The vaccine, as you've seen, can be remotely delivered.

So we deliver it generally from a, from a helicopter. And, The, the vaccine is relatively cheap. Most of the costs involved are, are helicopter time and, and the veterinary costs, the vaccines themselves are, are relatively cheap.

So in, in the bigger picture, so it's, it's not an expensive process. The contraceptive effects are reversible. So once we start to, remove animals from the programme, within a fairly short period of time, we start to see them reverting back to normal, reproductive behaviour.

Another really important thing to take into consideration here is that, the vaccine has no effect whatsoever on, on pregnant animals. The if an animal happens to be included that's already pregnant, she'll carry that, that calf to full term without any complications whatsoever. The effect of the vaccination really is far, you know, is effective at a, at a much earlier stage in the, reproductive process.

So, no effect on pregnancies. We've seen no short or long-term significant health effects from it. A lot of these these, research protocols as they were conducted, Contained a, a significant, behavioural, aspect to the, to the research protocol.

And, and there really seems to be no significant long or short-term health effects whatsoever. There's no real effect on, on social behaviours in the short term or the long term either. And, really importantly here, it's really targets, specific.

So, once we apply the vaccine, it, this agent or the contracept The agent does not pass through the food chain whatsoever. And, that's something that would be a little bit different with hormones if we were using hormones, potentially, you know, potentially, it's not that really important in, in elephants, but, but most wildlife species can potentially form part of the food chain. And, animals that are on hormonal contraception potentially can, affect, other animals further down the food chain.

So, You know, the PZP obviously has no effect there. And then the other important thing here is that, because it's very targetspecific, we can leave the dominant cows out of the pro protocol, and we can allow them to continue to breed and and have youngsters. And, we can select the rest of the females in the herd to contracept.

And so therefore, we have a much more reduced population growth rate. And that's really what our objectives are at the end of the day. The, very briefly there, what, the protocol is.

The, the initial primary vaccination is a, is a, double strength dose, of 400 mcg of the PZP. And we put this into a buffer solution. And, and then we apply a booster after that.

The booster is at half the dose. We only use 200 mcg for the, for, for the boosters, and, also in a, in a buffet solution. And, how the initial protocol works is we have a primary vaccination, and then we, we do a booster at 5 to 7 weeks post the, the primary vaccination.

And thereafter, from year 2 onwards, we just apply an annual, booster vaccination. And that, that appears to be sufficient to keep the animals, sufficiently contraceptive. So this little video I'm gonna show you here is just an example of what it looks like.

When we go in, this is a herd of about 20, elephants, of which we were gonna contracept 10 of those. And, yeah, so this, this whole process took us approximately, probably less than, less than 10 minutes to contracept the whole, the whole herd that we were targeting. So I'm just gonna let this run through quickly.

The elephants respond really, really well to through the helicopter. And, a good helicopter pilot is essential in order to keep the herd together. And, and then it makes it a lot easier for me and the helicopter to be able to administer the vaccine via via dart.

The, the darts have a, have a special, they, they're quite special darts in that . They, they have a before the market that as well. You can see these, I, I'll explain and mark it out shortly.

These elephants, they, unfortunately, they don't take very kindly all the time to elephants. And, I got two helicopters, and so it's, sometimes can appear to be quite traumatic. But fortunately, this process is, is really quick, and, and we only have to, to fiddle and, and annoy them at least once a year.

So, it's, it's really quite low invasive, low invasive process. And, they soon forget about it, but they certainly they don't forget about the helicopter. And So there's just a picture of, of, of what these marker dots look like.

So the, the dart has, has two chambers. 11 is for the, the vaccine, and the other one has a dye in it. And, once we've darted the animal, the vaccine is injected, and then the dye is ejected out of a side port, and then it marks the animal.

So those animals that we have already darted are easy to identify. We obviously don't want to, get confused. And once you, You know, once you're flying around and, and you, and you're herding these animals, it's it's quite difficult to, to know which individuals you have and have not done without having some form of marker system.

So these, these marker darts really work quite well. And, they stand out quite clearly. And it's, it, it, it helps us just to identify those animals nice and easily so we don't dart them twice.

Right, the question is, how, I mean, how long does it take for this PZP to stop or reduce population growth in a herd? That, I mean, that really depends on the number of cows that are treated. But if we treat all of the cows in a herd, then the population growth, by the 3rd year of treatment will be 0%.

And that's, that's not really how we base our models or our protocols. But, so what, what we're trying to achieve is some form of breeding, but ultimately to have a growth rate of, of 0%. And we have to take into consideration that there is annual mortality as well.

And the normal annual annual mortality is between 2 and 3%. So the models indicate that if we treat at least 75% of the breeding females, or approximately 75% of the breeding females, in a herd, and then, we take into consideration and mortality of 22 to 3%, that is sufficient to result. In a 0% growth rate.

And that's ultimately what we strive to achieve. It, you know, we may not implement that immediately, but, but ultimately, from a long-term perspective, the idea is to have at least 75% of the breeding females on the contraceptive programme, and ultimately resulting in a 0% growth rate. So, what's the practical application of this?

OK. The advantages are obviously, it's very effective contraception, and we can use it very accurately to manipulate population growth rates, which is important. We've mentioned there that we can leave the specific dominant individuals to continue to breed, and to have babies, and that keeps the, the welfare of the herd intact.

It has no negative effects on animal health. It, it doesn't enter the, the food chain at all, so it's not passed down to other species or other animals as well. And it's the most suitable, or the technique is most suitable to small stable populations, that have a range of ages of ages present within the population already and that are approaching their ecological carrying capacity for that reserve.

What are the negatives? Obviously, it has no effect on male reproduction at all, so we can't use it to manipulate males, whether we're looking at, at it from a reproductive point of view or whether we're looking at it from a, a behavioural point of view. It has no effect on males whatsoever.

And then the other thing, it requires accurate identification of the individuals. We, we need to vaccinate the same animals over and over again. So it's really, really important that, when I'm working on a reserve, that I have someone in a helicopter with me that is intimately involved, with, you know, on the reserve, and, and Most of these managers can identify individuals, and I know them very well.

And, it's important that I have that person in the helicopter with me to identify the individuals. And certainly the individuals that we don't want to have included in the programme, and they must be able to point those ones out very clearly. And then the rest of the females, we can just carry on and vaccinate as needed.

So that really sums up what the PZP vaccine is about and, and how it, it works and, and how we utilise it. The other technique, the other immunocontraceptive technique we use is the, GNRH vaccination. As I mentioned, it was really, designed initially for, or utilised initially for controlling, behaviour and, reproductive activity in elephant bills.

It will be effective in females as well, but we really don't use it much in females at all. So behaviour is a problem in these small reserves. They are very close family bonds that develop, and, strong hormone-driven instincts.

And, these can turn a, a quiet, placid elephant bull into something that's unmanageable and, and dangerous. It doesn't happen very often, but it does happen from time to time. You know, this aggression is directed at, potentially at, at other elephants, as well as, as well as other wildlife species.

And traditionally, what we really, what we, what we used to try and do is we try to control this behaviour by using behaviour modifying drugs, long-acting depot injections of drugs like prophenazine and, and Acu phase. They are long-acting members of the, the butrophenone groups of, of drugs. And, on a short term, from a short-term basis, it, we find them relatively effective, up to a point.

But the big problem is that they, they only really last for up to about 2 weeks, and then the effects starts to wear off. And unfortunately, these hormonal, Episodes do continue longer than that. And so, you know, if we're having to, to use, dropout darts to administer long-acting depot, calming drugs, it's, it's really not ideal.

I think we traumatise those animals a lot. And so that, that really does become a problem. And, and, Yeah, fortunately, we've been able to, you know, work around that by using, immunocontraception as our, as our tool of choice there.

And, it's, certainly paved the way forward for, you know, effective hormonal control, just to control these unwanted behavioural problems that we do find from time to time. So, how does the GNRH work? OK.

As I've mentioned, it is an immunocontraception. So after vaccination and a booster with exogenous GNRH, an exogenous GNRH conjugate, the body produces antibodies against that. But these antibodies, are also effective at, neutralising the endogenous GNRH within the body.

And it, It does this by, preventing the endogenous GNRH from binding to its receptor sites. And by doing that, then the hypophyal, hypothalamic grenadal axis is blocked and the reproductive hormonal cascade is broken. And yeah, essentially the animals are then sterilised as a result of this.

So what, what are the effects of this? As I said, we use it mostly in, in males. And what we see in in males is diminished, spermatogenesis.

We see reduced aggressive behaviour. In females, smaller uterus, reduced follicularar activity, and, and no signs of east risk. And what are the benefits then of this, this vaccine, particularly in the wild elephants.

We start to see less wandering of, of elephants. We're talking specifically of the, of the males, obviously. In these reserves, where, where we have, an interface between wildlife and, and humans, especially in, in environments where we have a lot of, agriculture, bordering on some of these reserves, elephants breaking out and raiding the crops is a problem.

We see less of that behaviour taking place once they've been on a contraceptive programme. Human elephant conflicts are reduced as well. We have much less aggressive activity in, in problem bulls.

And then also, we can use it for population management as well. In the captive elephants, population management, obviously very important. And then, of course, the, suppression of aggressive behaviour and the control of must in these bulls in captivity.

This is just a, a picture of a team. It's an international team that we put together. Well, there's a lot of South Africans here, ranging from, behavioural specialists to, wildlife veterinarians, and then also people that are really experienced with, with ultrasound.

So it was a nice collaborative effort from, you know, around the globe. A very effective team that worked very well together. So our research plan was, we had, we had 12 African elephant bulls that we, we included in the programme.

They were all aged between 8 and 30 years of age. And, we used a commercially available vaccine, GNRH vaccine, that was, Produced for the pig industry called Improvac. Some people will be, familiar with that.

We use it obviously at a much higher dose. We use 5, a dose of 5 mLs as a, as a single dose. OK.

And it's given by deep intramuscular injection. Very important, that it's given deep intramuscular. The, the drug is quite, the vaccine can cause quite a significant Subcutaneous reactions if it, if it is administered subcutaneously.

So, we ensure that if possible, we can give deep intramuscular injections. And then what happened was we, on a, on, basically on, every 6, on a 6-monthly basis, we would examine each of those 12 elephant bulls. And, each examination included an ultrasound examination.

Blood sampling was taken, semen was collected if possible. And, and there was a behavioural, evaluation on a continuous basis that was done. They also did just regular faecal sampling for the measurement of testosterone as well, just to try and correlate some form of pattern between faecal sampling and, and what our blood samples gave us.

And, so those were, those were all the, The processes and, and that was all the data that was collected at each interval. The protocol was, From day zero, we, we vaccinated, and, we did an examination at, at exactly the same time. So our first examination was done pre-vaccination, and then the animal was vaccinated, then just, just at the end of the examination.

The booster vaccine was given, 6 weeks later. And, and then at 6 months after the first vaccination, the, 3rd booster or the 2nd booster was given. And, 1 month after that was our Our opportunity for our second exam.

And thereafter, our examinations, coincided with, on basically on a six-monthly interval. It, towards the end, we extended that to a year. And, our exams were done, examinations were done 1 month after each, booster vaccination was given.

Just a, a, a little bit of anatomy here. This is what the, the internal, reproductive organs of the elephant bull are. Obviously, testes, for those that aren't, familiar with elephant anatomy, the testes or the testicles sit.

Intra-abdominally, so they're not external at all. And then all the other accessory sex glands, are closely associated there. We have, we find the ampula and seminal vesicles present in, in these pools, as well as, a prostate and the bulbar urethral glands.

And these were all things that we, we looked at and, and measured very closely when we did the ultrasound examinations. The, we did include some wild bulls. So there were some wild bulls included in the, in the, in the project, as well as, the captive bills.

The captive bus, we could work using a, standing sedation. The combination there was either deomidine or, or meatomidine, used together with buorphenil. And for the full immobilisation, of the wild bulls, we'd use etelphine.

The trade name is N99. We'd use a combination of etelphine and deomidine. Under normal circumstances, a lot of the immobilisation protocols for, for elephant will include, one of the other buttrophenone drugs known as azapparone.

Excuse me. And, But we don't use that, in our programme here, in our protocols because the zapperone potentially has, an inhibitory effect on ejaculation. And obviously, one of the things that we're looking at is sperm quality.

That's our, our key function here, or a parameter. And so we would like to try and collect semen. That was our objective.

And including zapperone was going to have an influence on that. So this is what the, the ultrasound examinations look like. These are the seminal vesicles.

And you can see this is just a diagram, just, demonstrating how the different sizes of the, seminal vesicles vary. But essentially, with time, the, the seminal vesicles, as the vaccination became effective, so the size of the seminal vesicles started to decrease. The, yeah, so that was, that was very characteristic.

We, we did, testicular measurements as well. So intra, for trans rectally, we were able to, to pick up the testes. We measured size, and we measured blood.

Flow as well. But essentially, we were looking at the size of the testes. That was our most important parameter.

We looked at testicular sizes. We could see that decreasing trend in the size of, of the testicles, as, As we progressed with the, with the protocol. Very significant.

And, and when we looked at some of the other accessories sex plans as well, just excuse me there for a second. When we looked at some of the other sex glands, the ampula, the ampula decreased significantly in size. The ampula are the, the storage vesic or the storage, chambers for, for semen.

And, we, anticipated that if our vaccination was affected, that we should see quite a reduction in size and, and in the Aula. And this was, this was clearly demonstrated. And we were able to clearly see them, pick them up and and measure them accurately on ultrasound examination.

Serum testosterone levels were, were very important for us. And, The effect was very dramatic. Even by the time we did our six-month, post-immunization, tests, the testosterone level had decreased significantly.

And by the time we got to 1 year, those levels had dropped down to, down to 0. So a good indication of how effective it really was. The semen collection was done in two different ways.

The standing elephants was manual prosthetic stimulation. So that really just involved, a manual stimulation of the prostate. Just using a gloved hand.

And, what that did was it allowed semen, release, especially from the Ampula. And we used these little special collecting vesicles underneath that the, the elephant would get an erection. And then gradually, he would release, A flow of semen that would, that would dribble down and that we were able, we were able to collect them like that.

The, rules that were mobilised completely. We, we used, electroejaculation. That picture there is, is Professor Birchinger, operating the, electroejaculator.

And, yeah, that was, a very effective technique as well. It took a little bit of, a little bit of practise to get the, the probe in the right place. And also, we had to, we had to, you know, design our own probes.

To get the electrodes in the right place so that we got the correct stimulation. But, within a short period of time, we were getting very good results, using the, the electroejaculator. The one, complication was that if you, if you didn't get it in the right place and you got anywhere near a bladder, then ultimately, you would end up with, a whole lot of urine contaminated semen.

And, that, that interfered a lot with the results. Because the, the urine obviously is toxic to the semen, so that potentially had problems there. The, the semen that we did collect, was analysed.

This is a, a, andrologist, a human andrologist, Professor van der Host. And, he developed a, a computer-assisted sperm analysis, programme. And, this, this was, was very useful for us.

He, he examined all of these, samples that we collected and he used this technique to, to look at, sperm mortality, motility. And it gave us a really good idea of, when we did find sperm. Early on in the, in the protocols, you know, how, how effective were those sperm likely to be?

So this, this was a system we used there. And then we also looked at electron microscopy on the sperm as well. One of the, this was at, at the second examination, these examples, it just shows how quickly this vaccination actually kicked in.

By the time we did our, our second exam at 6 months, most of the, the bulls that, that we collected semen from. Had some form of, of sperm defects, and, a lot of detached heads, unusual, tail structures. And when they were examined on, on electron microscopy, you could see quite clearly all the deformities, that had taken place there.

So, even by 6 months, the, the sperm quality had reduced considerably. The process was for, for ultrasound examination, was, was quite lengthy. The, the rectum obviously had to be cleaned out, very well.

So we just used, a hose pipe with, with lots of water. In the field, we would have a, a vehicle that was, a pickup vehicle with a tank on the back and a, and a pump, and we would, we would just constantly flush the, the rectum. And, and just clear out all the faeces.

It was a bit of a messy affair. But once we got them nice and clean, we've got really, really good, ultrasound interface so that we could visualise those internal sex organs quite well. It's, the, you know, obviously, elephants spend a lot of time browsing, and they, they particularly like a lot of the thorn acacia.

So, some of that, that faeces that, that passes through, not all of it is completely digested. And so it's, there's a lot of, sharp, sticky, or, you know, fibrous type material that's there, which makes life quite awkward when you're trying to do ultrasound. So, it was an important process.

You had to just get this flushing done properly. And then, yeah, the standing, the standing balls were actually a lot easier to, to do ultrasound on. it doesn't appear to be, so from this picture, but it was, look, it's a, it's, it's quite a physical affair to get in there, one has to get in nice, nice and deep.

We did have, probe extenders so that we could attach the, the probes. And we just use a normal curvilinear probe. It's not a rectal probe that we use.

We use a normal cur curvilinear probe. And there's a Space in an elephant to, to do that. It gave us a much better interface, especially at an angle, we were able to, to manipulate the rectum a bit better with that, to get closer to the, the testes and stuff, which sit quite high up, kind of at the, the sort of like a 10 o'clock and a, and a 2 o'clock position.

So it was, it's quite awkward to try and, and get up there. But the, the curvilinear probe worked really well to, to do that. And in the standing position, we were really, you know, able to access those, those testicles and, and the rest of the organs quite easily.

And the standing sedation here, you can see a typical example. Once these pills, their drugs kicked in. They really stood really nicely for us.

And, the real typical sign is that, that flaccid trunk. That's, that's kind of, what I was looking for as the, as the person responsible for, for the, sedation and the immobilizations. The, that flaccid trunk is quite typical.

So, if ever one, does have to do standing sedations, that's a really good indication. If they start to lose control of their trunk, that, that's a, and, you know, a really good idea or indication that your drugs are starting to kick in nicely. One has to be really careful working with these animals.

Although they, these captive bulls are are fairly well habituated to people, you know, invasive stuff or, you know, if they feel threatened, they can still be very, very dangerous. I mean, that trunk of theirs is, is extremely powerful and, and, and dextrous. And so one has to be really careful.

But, if You see a nice flaccid trunk like that, that's, that's a really good example that they, that they, you know, the immobilisation is, is really working well. Also, the, the relaxation of the penis as well is also a really good indication, just like it is in horses as well. You get a nice relaxation of the penis as well.

The, on the, on the ground, the, the, the fully immobilised elephants, that, was a little trickier. Depends on how they went to go and lie. Elephants, and, full immobilisation, need to lie on their side.

The anatomy dictates that they must lie on their side to breathe properly. So we always had to position them on their side, which made accessing, the testicles tricky at times. So we had to spend a little bit more time, finding them.

And, and, and trying to get deep enough in. There were occasions when we just really couldn't get to both testicles. But, that was just unfortunately something that we had to work around.

But a, a little bit trickier, in the field, also less controlled environment, for the ultrasound, sun played a role as well. Sometimes it was quite warm. So it became a little trickier in the field as well.

That's typical of what it, you know, the sort of, the scene looked like, these elephants lying on their sides. The one really important The thing to do is, once the animal is immobilised, is to be able to, to get control of the penis. The penis doesn't stay protruded for, for particularly long.

And once it starts to retract back into its sheath, that sheath is, you know, is, is probably close to 2 metres long and the penis retracts right deep into, into there. And if you, if you don't get hold of it early enough and it retracts in there, then you just got no chance of getting it out. So, we always had someone assigned to, To picking it, you know, to holding on to the penis, getting control of it, and then keeping it out.

And then, while we prepared all the other, techniques, doing the ultrasound first, and you know, we would end off by doing the, the semen collection right at the end, but we needed to have the penis out all the time for that. All right. And yeah, so that's really briefly describes how the, what, what the GNRH protocol is, and, and how we went about the research around it.

And, it was clearly very effective. And we've seen such good results with regards to behaviour and stuff. And obviously, on a long-term basis, it's very effective in these elephant bills in controlling, testosterone levels.

And, that has two effects. One is it contracepts the elephant, and secondly, it also controls behaviour quite nicely where it's necessary. And so, just in summary then, how do I apply all of this knowledge?

What, what, how, how do I approach it all? Which, which technique do I use first, or how do I go about it? And, and really what I, what I look at is, is I start off normally with a founder population, bearing in mind that when we, when we introduce a, a founder population, many of the cows are already, are, are already pregnant, OK?

And, and so what we need to do is, we need to allow those calves, or those cows to then, to calve down. And that Gives us a, a good indication after a couple of years, exactly where the population stands. But in the interim, we don't want the females to fall pregnant again.

So, this is the time when I target the bulls. So, my protocol is initially, I start with a GNRH vaccination programme, where I, I focus on the bulls. Initially, and I allow the females to, to continue normally, the pregnant females to have their calves.

And then after a couple of years, normally around about, 5 to 6 years after the reintroduction. That's so, that's a good time to reassess the situation. The calves are then, round about the newborn calves, somewhere between 3 and 5 years old.

And, and that gives me an idea of where the population is, is heading. It's, allowed the, you know, the adults to, to nurture those youngsters. So they, they're generally quite content.

And, you know, they've got a, a relatively long carving interval as well. So nothing really seems to be out of, out of the ordinary for them and, and, and life carries on as normal. And it's just the, it's just the bulls that we've, we've targeted there.

We, we don't have to do all the bulls, only those that are, of reproductive age. And those are the bulls that tend to be probably over about 12 years of age, that really, The, the main, the main target balls should be the bulls above 20. But we do, we do sort of, have a, a little bit of a safety net in there.

So, anything from about 12 years of age and older, those are the bulls that I would, that I would consider targeting to put onto the GNRH. And, and then after about 5 years, then I reassess. And this is about the time where I feel that, the, some of the females within the herd need to start, falling pregnant.

And that's when I switch over to the PZP. And then I sit down very closely with the management there. And we select out the, the dominant cow, perhaps the, the, the cow that's in charge, and, and one or two, if necessary, one or two other, dominant, or prominent females.

And we, we don't include them into the, Into the programme. And and then I'll take all the other adult females, from about 10 years of age and older, and they'll all be put onto the PZP vaccine. And at the same time, then what I'll do is I will start to take the, bulls off the GNRH as well.

And invariably, as long as those bulls haven't been on, on the GNRH vaccine for too long, those dominant bulls start to, return into must again. And, and then ultimately, they can start breeding with the females. And then we strive towards achieving that stability where we've got about 75% of the females that are on the, on the protocol.

And if we take into consideration the mortalities, we should be able to maintain a, a 0% growth rate. We can increase that, growth rate a little bit initially, if we, if we're striving to increase the population size a little bit. But once we start to reach the carrying capacity, that's when, we need to make sure that we've got an adequate number of the females on the contraceptive programme.

And by combining these two, you know, protocols and methods, we are able to very accurately, manipulate and, manage elephant populations, particularly in the, the small, populations that exist on small reserves, ecotourism reserves. Good. I think that's about it.

I, Yeah, I don't think there's anything else. And I hope that was, that was all clear. And yeah, I'm, I'm quite happy if there's, if there's anyone that would like to ask, questions, yeah, I'm more than welcome to, to answer those questions if I can.

Thank you, Doctor Brandon for this fantastic talk. It is always very interesting to hear about these topics on animals that are so different from our daily practise. So thank you very much.

It seems that we don't have any questions and we are out of time, so, see everyone in another webinar and if anyone has a question, please email to dawn at the webinarett.com. Oh, here we have one question, so.

Oh, it says excellent presentation. Oh, good. So yeah, if anyone has any questions, please email them to dawn at the webinar vet.com and see you in another webinar.

Bye bye. Bye, bye bye everyone.