An unseen threat to cattle, carried by wild predators, has been confirmed in the forests of Slovenia.
In the vast, forested landscapes of Slovenia, the howl of the grey wolf and the call of the golden jackal are signs of a thriving ecosystem. Yet, a recent scientific discovery has revealed that these wild canids are carrying a hidden passenger: the parasite Neospora caninum.
For the first time, researchers have molecularly confirmed the presence of this parasite in the feces of Slovenia's wolf and jackal populations. This discovery, published in a 2023 study, sheds new light on the silent circulation of a pathogen that is a major cause of economic loss for cattle farmers worldwide and a potential threat to the health of our domestic dogs 2 8 .
Key predator in Slovenian forests
First confirmation in wild canids
Major cause of bovine abortion
Neospora caninum is a microscopic, single-celled parasite first identified as a distinct species in 1988 5 . It belongs to the apicomplexan phylum, a group of parasites known for causing significant diseases, and is a close relative of Toxoplasma gondii 4 .
Oocysts are shed into the environment through feces and can survive for months in suitable conditions, contaminating soil, water, and vegetation.
For years, the sylvatic (wild) life cycle of N. caninum has been somewhat of a mystery. While wolves and coyotes in other regions were known to be definitive hosts, the role of wildlife in Europe, particularly the rapidly expanding golden jackal population, was unclear 8 .
A team of researchers from the University of Ljubljana set out to change this.
The challenge in detecting N. caninum in wildlife is that oocyst shedding is intermittent and occurs in low numbers. The researchers needed a highly sensitive and specific method to find a genetic needle in a haystack of fecal matter.
| Species | Regions Sampled | Years |
|---|---|---|
| Grey Wolf | 5 of 12 regions | 2013-2020 |
| Golden Jackal | 7 of 12 regions | 2013-2020 |
The molecular detective work yielded clear results. The study confirmed the presence of N. caninum DNA in the feces of both wild canid species, marking several firsts 2 8 .
| Species | Samples Tested | Positive Samples | Prevalence |
|---|---|---|---|
| Grey Wolf (Canis lupus) | 42 | 3 | 7.1% |
| Golden Jackal (Canis aureus) | 39 | 1 | 2.6% |
First molecular detection of N. caninum in the grey wolf population of Slovenia.
First detection of N. caninum DNA in the feces of a golden jackal anywhere.
Direct evidence that wild canids are shedding the parasite into the Slovenian environment.
Map visualization of sampling locations across Slovenia's 12 statistical regions
Uncovering a hidden parasite requires a sophisticated molecular toolbox. Here are the key reagents and materials that made this discovery possible 8 :
| Reagent/Material | Function in the Experiment |
|---|---|
| Primers & Probe | Short, custom-designed DNA sequences that bind exclusively to the N. caninum Nc5 gene, enabling its targeted amplification and detection. |
| Real-Time PCR Master Mix | A chemical cocktail containing the enzyme (Taq polymerase) and nucleotides (dNTPs) necessary to build new DNA strands during the PCR process. |
| Digital PCR (dPCR) | An ultra-precise technology used to validate and calibrate the qPCR assay, ensuring its sensitivity and accuracy for absolute quantification. |
| N. caninum Positive Control | A known sample of N. caninum DNA, used as a reference to confirm the test was working correctly in each run. |
| Fecal Samples | The primary source of material, collected postmortem and stored at -80°C to preserve genetic material and eliminate risk from other viable pathogens. |
The detection of N. caninum in wolves and jackals is more than just a record of occurrence; it has real-world implications for wildlife, agriculture, and disease management.
The rapid expansion of golden jackals throughout Europe brings them into closer contact with human habitats and livestock farms. Their unselective diet and mobility make them ideal for spreading parasites across the landscape 8 .
This study proposes the golden jackal as a definitive host with "hypothetical epidemiological importance," a new factor to consider in the fight against neosporosis 8 .
This research highlights the growing importance of molecular tools like qPCR in wildlife disease surveillance. Traditional methods are often insufficient for detecting low-level, non-clinical infections in wild animals.
Molecular detection provides a powerful way to monitor pathogen flow between wild and domestic animal populations, a concept known as "One Health" 8 .
Monitoring pathogens in wild canid populations
Protecting cattle from neosporosis infections
Maintaining balanced ecosystems and food security
The discovery of Neospora caninum in the feces of Slovenia's wolves and jackals is a classic story of modern science: using advanced genetic tools to illuminate the hidden connections within ecosystems.
It reveals a web of transmission where wild predators, their prey, and domestic cattle are all linked by a microscopic parasite.
As wolf populations recover and jackals expand their range, understanding these dynamics becomes crucial. This research provides vital knowledge for farmers, veterinarians, and conservationists, helping them to develop strategies that protect both the economic viability of agriculture and the health of Europe's magnificent wild canids.