WildWildWildWild Vet AfricaVet AfricaVet AfricaVet Africa GnRH Vaccine in Elephants:GnRH Vaccine in Elephants:GnRH Vaccine in Elephants:GnRH Vaccine in Elephants:

In this, our first Wild Vet Africa newsletter, we share with you a research project

that Wild Vet Africa and Africademy had the privilege of hosting recently.

Imke Lueders , sponsored by the International Elephant Foundation, recently lead a team of

specialists in their fields that marked the beginning of her research study to investigate and test

the effect of GnRH vaccine on the reproductive organs of bull elephants. This collaboration

included organizations such as the Institute of Zoo and Wildlife Research, Berlin,

Germany, the University of Pretoria,

RSA, the Universitof the Western Cape, Cape Town, RSA and Non-Governmental

Institutions Such as the African Lion Safari,Cambridge, Canada, the KingfisherConservation Biol

ogy Laboratories, Stouffville, Canada and Africa-Catchco Wildlife Service, Pretoria, RSA.

The Knysna Elephant Park and Africademy are proud to be associated with these organizations

in what Luders described could be ground breaking work for future elephant population control

and the management of ‘problem’ bulls.

Ultimately, the researchers hope to establish whether the GnRH vaccination could be effective

as an immuno-contraception method for population control of wild elephants. If the outcomes

of this study reveal that GnRH vaccine does reduce fertility in bulls and that it is effective in

reducing MUSTH, the vaccine could be considered as a tool in the arsenal of options for

population control. In addition, they hope to make it applicable for aggression suppression in

wild bulls; as well as improving the quality of life for captive elephant bulls by suppressing

musth and inhibiting associated behavioral problems.

Within the South African captive elephant context, this vaccine has potential for improved

management of elephants in several areas:

• Fertility and breeding control

• Suppression of musth and associated behavioral problems

• More effective management and handling of ‘problem’ bulls

• Increased safety for elephant handlers

At the turn of the century (1900) there were an estimated 4000 elephants in Zimbabwe.

Stevenson –Hamilton, founding game warden of the Kruger National Park, reported that there

were only a few elephant tracks recorded near the Olifants Gorge. Regular records of elephants

were noted by Stevenson-Hamilton in 1905. He referred to these elephants as strays from

Mozambique avoiding heavy hunting activity from that region.

His records show that for the next thirty years elephant numbers grew to around 400 (1938)

and by the mid sixty’s there were around 7000 elephant at Kruger National Park. Today,

Kruger’s elephant population is recorded at around 14 500.

Zimbabwe’s Hwange National Park recorded 700 elephants in 1928, with the population

increasing to 600 by 1960. This population swelled to 60 000 by the year 2000 despite 20 000

elephants removed during the 1960’s, 1970’s and 1980’s.

It is no secret that the ranges available to wildlife are reducing versus mans increase in

population. In 1994 culling as a means of elephant population control was halted, primarily

from the pressure placed on Parks through animal rights groups. This brings to mind the range

of tools conservationists have at their disposal to manage populations.

Facts you need to know about GnRH

1. Vaccine is non-invasive, but has a similar effect to castration

2. It has been successful in domestic (boars, horses) and non-domestic species (white-

tailed deer, bison and other zoo animals)

3. It has been shown to have great potential in elephant reproduction and behavioural

management (for African and Asian species)

4. Simple to apply by darting

5. Reduces aggressive behaviour / musth of bulls

6. Low biological risks – it is not a hormone treatment and is therefore expected to have no

negative side effects.

7. It is reversible

8. It is potentially long-acting and only needs to be repeated once annually, or even less

frequently

9. More cost-effective than other methods

10. Fewer animals need to be treated, as it takes action on the males rather than the females

The project

The first round of the project involved:

• Anesthesia

• Measuring the testicles and aspects of the testicles specific to reproduction and sperm

production via trans rectal ultrasound

• Sampling: Blood, Faeces and Semen

• GnRh Vaccination (Improvac )

• Study of the quality of the sperm

Anesthesia

Anesthesia was performed by the capture expert Dr. Douw Grobler, who has more then 20 years

of experience in his field and in particular with elephant anesthesia.

He applied two types of anesthesia:

• General anesthesia: One elephant was totally sedated, leaving the elephant in latero-

lateral position.

• The rest were slightly sedated within a facility prepared for the occasion. The

administration of the drug was injected intramuscularly.

All the animals are in excellent condition and all anesthetics were performed successfully. The

elephants ranged in age between 15 and 22 years old.

Once sedated, ultrasound examinations were performed and semen samples were collected.

Blood and feces Samples

University of Pretoria, Section of Reproduction, South Africa

Blood samples were taken by Dr. Pr.Henk Bertschinger to measure testosterone levels and

analysis of the reaction of anti-bodies. A primary marker of vaccine efficacy will be to

determine testosterone levels. The reduction in the level of the hormone will be regularly

reviewed in the blood or feces / urine of males.

Blood samples will be analyzed at the University of Pretoria, under the supervision

of Prof. Henk Bertschinger. Testosterone levels will be analyzed also in dung.

Blood was also collected to assess the antibody titer against GnRH. This will be performed in a

commercial laboratory in South Africa.

Urine and feces samples will be taken two to four times per month. The urine and fecal

samples will all be shipped to Canada, where they will be analyzed at the

Laboratory of Conservation Biology, Kingfisher International Inc. (FKI), Stouffville, Ontario.

Vaccination

Prof. Henk Bertschinger who applied the vaccination will check to establish whether

immunization was successful and it will also be important to find out how often revaccination is

necessary.

Ultrasound

The testicles of bull elephants unlike most of the species are intra-abdominal. Ultrasound was

applied trans-rectally in the bulls in two ways: in a restraint device with slight standing sedation

(5 bulls) whilst one bull was sedated using general anesthesia. A highly sophisticated portable

ultrasound device (4D ultrasound “Voluson i”, GE Healthcare) for optimum imaging and data

recording was used to measure the relevant reproductive organs. Testicular and accessory sex

gland sizes was recorded, a process that will be repeated again in October this year. Imke

Lueders and Charlie Gray are experts in elephant ultrasonography and have been instructors at

the annual ultrasound workshop at the African Lion Safari for the last five years.

Semen Samples

Prof Van der Horst (University of the Western Cape (UWC), South Africa)

In the case of the elephant that was under general anesthesia we used electro-ejaculation to get

sperm samples and for the remaining elephants, rectal prostate massage was performed. Semen

collection was performed by Charlie Gray and Imke Lueders.

Sperm was assessed for volume, density, sperm count, motility and morphology. As an expert in

his field, Prof. van der Horst will receive ejaculate samples to perform Computer Aided Sperm

Analysis (CASA). This has been proven highly valuable in previous trials (van der Horst et al.,

2010a,b,c) .

Body Condition and Behavioral monitoring

Photographs were taken of the bulls before and during the vaccination trial to record possible

exterior changes. A common effect of testosterone suppression is the loss of muscle mass.

Elephant handlers will be asked to evaluate behavioral changes of the treated bulls by

completing a questionnaire and students will complete behavioral studies where possible.

CONCLUSION

The study will involve at least three vaccinations within a period of 12 months and the regular

monitoring of antibody titer in the blood, physiological and behavioral changes, changes in

reproductive organ anatomy and semen quality and hormonal changes.

We have recently loaded a short video clip that describes this process and the processes that

will follow.

Future measurements will determine whether the vaccine will have the desired effect on the

testes and their ability to produce quality sperm. Similarly, behavioural studies will parallel the

measurement of the stress hormone in the dung. This will give an indication of whether

aggressive behaviour diminishes with vaccinated bulls.

Delegates attending Wild Vet Africa will be exposed to the elephants involved in the sample

phase of this project and we will debate the merits of this research study as a solution to

elephant population control versus female birth control methods.

Know more about GnRH vaccine and Wild Vet Africa Courses in facebook Wild Vet South

Africa www.Africademy.com