Shamwari Conservation Experience

Elephant fertility research update 2016

I was lucky enough to participate in this research project as a volunteer back in 2013 and feel it’s fitting to be able to personally communicate the substantial contribution Shamwari has made to this research.

Let me start at the beginning. This vital project into effect of a GnRH vaccine on the fertility of elephant bulls has been running at Shamwari Game Reserve since May 2012. The team leading the project are Professor Henk Bertschinger (Faculty of Vet Science of University of Pretoria), Dr Imke Lüders and Ilse Luther (both researchers associated with UWC) as well as a private vet, Dr Brendan Tindal. The Shamwari bulls, Jabulani and Mashatu, are part of a study where the effects of the GnRH vaccine Improvac on the semen qua

lity and size of the internal reproductive organs of elephant bulls is being tested. In the past it has already been established that the vaccine suppresses testosterone secretion and thus prevents musth and testosterone related behaviour in bulls. This was a key visit to the reserve, to see if effects the vaccine is in fact reversible after ceasing treatment.

Currently there are 45 bull elephants being treated with GnRH vaccine to control musth and aggression in SA and Zimbabwe. A similar vaccine was initially tested in 2003 to see if it could control testosterone related behaviour and musth. Captive and occasionally free-ranging bulls become difficult to manage once they enter puberty and, at a later age when they enter a musth cycle, they can be extremely aggressive and endanger the lives of humans and other animals. In Asia such bulls are often put into leg chains and starved to make them go out of musth. These severe measures are a welfare issue and unacceptable. In Africa, if no land can be found to release such bulls they are often shot. The experimental vaccine tested was found to be successful at down-regulating aggressive behaviour and musth, and fortunately in 2006 Improvac became available in South Africa. Following testing of the vaccine it has since been used in many bulls. The main goal of the current project was to investigate the effects of the vaccine on fertility of bulls as this had never been tested before. If found to be effective in controlling fertility Improvac and other GnRH vaccines have the potential to be used as a male contraceptive for elephant population control. You may ask the question, why is this necessary? The answer is simple; elephants are being poached at an alarming rate in Africa, yet in South Africa their populations are booming and overpopulation of the largest land mammal is a potentially dangerous situation for any environment. All ecosystems have a fine balance, especially one with fences which stops the free movement of animals like in the past. A private game reserve, like Shamwari, needs to manage its wildlife population so that the vegetation isn’t negatively impacted by its inhabitants. It’s commonly known that the elephant can be the most destructive of all, through its sheer power and feeding capacity it has the nickname “the demolition artist”. Therefore, controlling the population is a necessity to ensure the entire ecosystem is not only stable, but flourishes.

There are a few options for population control; some more appealing than others. Translocation is one option, moving elephants to new breeding groups at other reserves, providing there is demand this option is always being explored and often used. Culling is another option, the least appealing for a conservation focused operation and one that everyone is desperate to avoid. The third option is twofold – contraception. Contraception of elephant cows which is successful and least invasive, which has been ongoing since 2000 when the porcine zona pellucida (pZP) vaccine was first employed in Mkalali. It was found to be 100 % effective as an elephant contraceptive for cows, if each cow could be treated regularly as required. The question Professor Bertschinger and company wanted to answer was, is Improvac a possible alternative for controlling smaller populations by treating the bulls?

The answer is affirmative in all 17 bulls tested as after 6 and 12 months there were dead and no sperm, respectively in their ejaculates. The question remaining however was, would the bulls return to normal fertility and a musth cycle if treatment was discontinued.

Why is this important? This is integrally linked to wildlife management. If reserves are able to control reproduction rates within the elephant herds keeping numbers at a manageable level, then culling or translocation are no longer an inevitability. But if circumstances allow for the herd to grow again, simple discontinuation of the treatment will allow for bulls to produce sperm and breed again. This means there is minimal impact to the elephant’s natural existence and interference is minor.

Furthering science is one of those great debates, science often means experiments, testing and negative impact on the specimen involved. I understand that, however, the beauty of science is that used in the right way, we can create solutions for potentially devastating situations like mass culling, which I believe is a great purpose and end goal. I'm no scientist, however, we no longer live in a world of free-roaming animals, that’s fact, even if it is our long-term goal to open up corridors for greater migration opportunities for all animals. Realistically though, to reduce pain and suffering to elephant populations in the future, this scientific approach is vital and a necessity.

So what do the scientists do once the animal is sedated? Their two goals are clearly seen in the accompanying video. One is the collection of sperm for analysis and the other is assessing the size of the internal reproductive organs, specifically the testicles and prostate, by means of transrectal ultrasound.

Semen is collected by inducing erection and ejaculation by means of transrectal electrical stimulation which uses a very low current. It is routinely used in conscious rams and bulls and is well tolerated. The stimulus is applied to the nerves that supply the semen ducts, prostate and other glands and the nerves that supply the penis for erection and ejaculation. The semen is collected in giant condoms by one of the research team, placed into a cool box at room temperature and immediately flown back to the laboratory for examination. It requires great team work and expert knowledge of the biology of an elephant to bring this all together whilst the animal is anaesthetized.

The focus on the testicles and the prostate centres on the size, understanding any variation and impact the vaccine has had. They also take blood for testosterone analysis as part of the reversal assessment.

The outcome of the day was enlightening and scientifically ground breaking. Jabulani, who is 38 years old now, had good semen meaning that the vaccine effects had in fact been reversed. Whereas Mashatu, the younger of the two bulls, had not. This suggests that his age probably plays a role, since we know that in domestic animals, younger animals take longer to reverse. This outcome is extremely important in terms of employing the vaccine as a contraceptive in elephant bulls. Shamwari has thus made a valuable contribution to the conservation of elephants and we are so proud to have been part of this project. Our volunteers have experienced something life-changing and unique, been part of something extraordinary and will never forget this day or the emotions it evoked.

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Elephant Research

Elephant Research