Ed Netherlands
Dr Edward Netherlands

As a young boy Dr Edward Netherlands was always interested in working with animals.

He could often be found collecting all kinds of reptiles and frogs in his spare time.

It was no surprise that when the time came, he would enroll for a BSc in Zoology and Botany at the North-West University.

Above all, it was in his postgraduate studies that his interest in research took off and went into overdrive.

“I was given a project on frog blood parasites in Northern KwaZulu-Natal – I just could not get enough. I carried on with my master’s and doctorate working on the blood parasites of frogs,” he tells the FBIP.

As a result his work on frog blood parasites provided the perfect scaffolding for his current work.

His recent focus is on the blood parasites of one of the most endangered mammals on earth – the African wild dog (Lycaon pictus).

Approximately 6 600 African wild dogs remain in the wild.

African wild dogs

The African wild dog is an iconic predator in the wild landscapes of the African continent with interesting characteristics.

Firstly, they are social animals that gather in packs of up to 40 and are highly effective predators. They are even more efficient than top predators like lions and targeted prey rarely escape.

Secondly, their role in the environment is crucial. Here they control the size of prey populations and eliminate sick and weak animals. In this way they help maintain the natural balance and improve prey species.

Further, according to African Wildlife Foundation, the main threat to African wild dogs is the loss of their living spaces through habitat fragmentation.

A secondary, but not less important threat, is the extinction of small populations due to infectious disease.

Consequently, this is where Netherlands brings his knowledge and skills to bear.

Blood parasites

Hepatozoon
Peripheral blood gamont stages of a species of Hepatozoon within its mammal host neutrophil.

He explains that species of Hepatozoon are blood parasites that are known to infect a wide range of host species. These include amphibians, reptiles, birds and mammals.

While most hepatozoons infect amphibians and reptiles, species that infect mammals such as cats and dogs, cause a clinical disease known as canine or feline hepatozoonosis.

Hepatozoonosis – a tick-borne disease – is transmitted when infected ticks are ingested by the host.

Clinically, infections range from being asymptomatic with a low intensity, to a severe disease in cases with higher intensities.

Host switching

In domestic dogs, Hepatozoon canis mostly produces a “subclinical to mild disease”. However infections with Hepatozoon americanum (a closely related species) are frequently fatal to their hosts.

Meanwhile this second species (H. americanum) only recently crossed the species barrier from wild hosts to domestic dogs.

“What this tells us is that if host switching of the parasites does occur between, for example African wild dogs and domestic dogs, we could see a more fatal disease pass through populations.

“This could be especially problematic for an endangered species and makes it crucial to monitor these species and the parasites they host,” he says.

High prevalence

The Netherlands et al. study was published in the March 2021 edition of International Journal for Parasitology: Parasites and Wildlife.

The study provides the largest dataset of Hepatozoon canis genotype infections in free-ranging African wild dogs.

Between 70% and 90% of individuals from this population were found to be infected during sampling events.

Consequently, this high prevalence shows how effectively these parasites are transmitted between individuals.

Netherlands says this knowledge is important. Above all for conservation areas such as the Kruger National Park, which protects the largest African wild dog population in southern Africa.

Why is this study important?

Therefore, the study provides a framework on the diversity of Hepatozoon blood parasites in the largest population of African wild dogs.

In addition, it has also generated the largest dataset of molecular data for these parasites from these host species.

Furthermore, African wild dogs have become an ecotourism icon for various reasons which likely includes its rarity.

African wild dog
African wild dog with prey carcass.

The species wellbeing is thus of great importance to the South African bioeconomy – an overarching theme of the Foundational Biodiversity Information Programme (FBIP)

Netherlands says conserving and protecting our biodiversity is important for all South Africans.

In conclusion, he says that best way to do this is to be able to make informed decisions for the protection and survival of species. Most importantly for those classified as Endangered.

“Through constant monitoring, and not only of the charismatic species, but also their parasites and potential diseases they may cause, knowledge can be gained on how to optimally protect these species.”

This study was funded with an FBIP Small Grant to Dr Marianne Pretorius (North-West University). The FBIP is funded by the Department of Science and Innovation (DSI) under the Global Change Programme and is jointly managed by the National Research Foundation (NRF) and the South African National Biodiversity Institute (SANBI).