Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Study Detects Deadly Fungus in Southeast Asia’s Amphibian Trade

07.03.2013
Wildlife Conservation Society and National University of Singapore discover American bullfrog is spreading Chytrid through commercial trade
A team of scientists led by the Wildlife Conservation Society (WCS) and the National University of Singapore (NUS), revealed in a new study, for the first time, the presence of the pathogenic chytrid fungus (Batrachochytrium dendrobatidis) in amphibians sampled in Singapore. And the American bullfrog may be a central player in the spread of the disease.

The study appears in the current issue of the journal EcoHealth, and is the first to consider the role that Southeast Asia’s commercial trade plays in the spread of amphibian pathogens.

Demand for amphibians through local and international trade is high and fueled by use of frogs as pets, food, bait, and as a source of traditional ‘medicine.’ More than 40 percent of amphibian species are in decline globally due, not only to chytrid fungus, but also overharvesting, competition from invasive species, habitat loss, pollution, and climate change.

In the study, scientists collected samples from 2,389 individual animals in Lao PDR, Cambodia, Vietnam, and Singapore at 51 different sites including farms, locally supplied markets, pet stores, and from the wild.

The molecular testing of samples was led by Dr. Tracie Seimon at WCS’s Molecular Diagnostic Laboratory at the Bronx Zoo. Results showed that frogs from Lao PDR and Vietnam tested negative for chytrid. In Cambodia, one frog intended for food tested positive. In addition, 74 animals in Cambodia and Vietnam were screened for ranavirus and tested negative, suggesting that these specific pathogens are not yet a conservation threat in species tested from these countries.

In Singapore, however, 13 samples tested positive for chytrid and represent the first report of chytrid in the territory. Eleven of those samples were collected from four pet stores and the remaining two were taken from amphibians in the wild.

The scientists noted that the chytrid detections were most prevalent in the American bullfrog (Lithobates aka Rana catesbeiana), a common species in the trade and one that is tolerant of chytrid infections.

“Finding chytrid in four of the seven Singaporean pet stores we sampled is cause for concern,” said lead author and WCS Scientist Martin Gilbert. “Since the American bullfrog is able to tolerate this pathogen, it may act as a carrier for spreading chytrid to the region when it is imported through commercial trade.”

In another alarming discovery, the scientists found that all 497 frogs sampled from 23 frog farms in Vietnam had skin lesions ranging from swelling and inflammation to ulcers and deformed or missing digits in the most severe cases. Disease examination revealed four of the animals had bacteria associated with the lesions that in two cases appeared to have spread to other organs.

While the bacteria and its role as primary or secondary pathogen could not be positively identified, the scientists noted that frog farms could serve as a source of infection for the wider environment.

The study noted that lesions among frogs raised at commercial facilities in Vietnam are of particular concern, in light of the low level of bio-security that exists. All of the farms in the study disposed of untreated wastewater directly into natural watercourses, which becomes an avenue to spread infection to other places and other species.

According to the authors, the World Organization for Animal Health (OIE) requires its 174 member countries, which include the four countries in this study, to conduct surveillance for chytrid fungus, report confirmed cases, and implement measures to control their spread.

Co-author of the study, Assistant Professor David Bickford from the Department of Biological Sciences at the NUS Faculty of Science, said, “In light of the fact that this emerging infectious disease is now known to be spread by commercial trade, it is in everyone’s best interest to eliminate it from the trade in live animals before both the native amphibian populations of Southeast Asia are affected and before it completely decimates the commercial trade and people are unable to make a living. This is not just about the frogs.”

The paper concludes, “There is an urgent need to conduct wider surveys of wild amphibians in Southeast Asia to determine the extent and severity of chytrid fungus and other infectious diseases among a range of species, and whether and how these change over time. Studies should focus on differentiating Batrachochytrium dendrobatidis strains that may be endemic to the region from exotic strains that may be introduced through routes including international trade.”

Authors of the study include Martin Gilbert of WCS; David Bickford of NUS; Leanne Clark, Arlyne Johnson, Priscilla H. Joyner, Lucy Ogg Keatts, Kongsy Khammavong, Long Nguyễn Vãn, Alisa Newton of WCS; Tiffany P. W. Seow of NUS; Scott Roberton, Soubanh Silithammavong of WCS; Sinpakhone Singhalath of the National University of Laos; Angela Yang, and Tracie A. Seimon of WCS.

For media enquiries, please contact:

Scott Smith (Mr)
Communications Manager
Wildlife Conservation Society
DID: 718-220-3698
Email: ssmith@wcs.org

Kimberley Wang (Ms)
Assistant Manager, Media Relations
Office of Corporate Relations
National University of Singapore
DID: (65) 6601 1653
Email: kimberley.wang@nus.edu.sg
About Wildlife Conservation Society (WCS)

The Wildlife Conservation Society saves wildlife and wild places worldwide. We do so through science, global conservation, education and the management of the world's largest system of urban wildlife parks, led by the flagship Bronx Zoo. Together these activities change attitudes towards nature and help people imagine wildlife and humans living in harmony. WCS is committed to this mission because it is essential to the integrity of life on Earth. Visit: www.wcs.org

About National University of Singapore (NUS)

A leading global university centred in Asia, the National University of Singapore (NUS) is Singapore’s flagship university which offers a global approach to education and research, with a focus on Asian perspectives and expertise.

NUS has 16 faculties and schools across three campuses. Its transformative education includes a broad-based curriculum underscored by multi-disciplinary courses and cross-faculty enrichment. Over 37,000 students from 100 countries enrich the community with their diverse social and cultural perspectives.

NUS has three Research Centres of Excellence (RCE) and 23 university-level research institutes and centres. It is also a partner in Singapore’s 5th RCE. NUS shares a close affiliation with 16 national-level research institutes and centres. Research activities are strategic and robust, and NUS is well-known for its research strengths in engineering, life sciences and biomedicine, social sciences and natural sciences. It also strives to create a supportive and innovative environment to promote creative enterprise within its community.

Kimberley Wang | Research asia research news
Further information:
http://www.nus.edu.sg
http://www.researchsea.com
http://www.wcs.org

More articles from Ecology, The Environment and Conservation:

nachricht New mathematical model can help save endangered species
14.01.2019 | University of Southern Denmark

nachricht Foxes in the city: citizen science helps researchers to study urban wildlife
14.12.2018 | Veterinärmedizinische Universität Wien

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Ten-year anniversary of the Neumayer Station III

The scientific and political community alike stress the importance of German Antarctic research

Joint Press Release from the BMBF and AWI

The Antarctic is a frigid continent south of the Antarctic Circle, where researchers are the only inhabitants. Despite the hostile conditions, here the Alfred...

Im Focus: Ultra ultrasound to transform new tech

World first experiments on sensor that may revolutionise everything from medical devices to unmanned vehicles

The new sensor - capable of detecting vibrations of living cells - may revolutionise everything from medical devices to unmanned vehicles.

Im Focus: Flying Optical Cats for Quantum Communication

Dead and alive at the same time? Researchers at the Max Planck Institute of Quantum Optics have implemented Erwin Schrödinger’s paradoxical gedanken experiment employing an entangled atom-light state.

In 1935 Erwin Schrödinger formulated a thought experiment designed to capture the paradoxical nature of quantum physics. The crucial element of this gedanken...

Im Focus: Nanocellulose for novel implants: Ears from the 3D-printer

Cellulose obtained from wood has amazing material properties. Empa researchers are now equipping the biodegradable material with additional functionalities to produce implants for cartilage diseases using 3D printing.

It all starts with an ear. Empa researcher Michael Hausmann removes the object shaped like a human ear from the 3D printer and explains:

Im Focus: Elucidating the Atomic Mechanism of Superlubricity

The phenomenon of so-called superlubricity is known, but so far the explanation at the atomic level has been missing: for example, how does extremely low friction occur in bearings? Researchers from the Fraunhofer Institutes IWM and IWS jointly deciphered a universal mechanism of superlubricity for certain diamond-like carbon layers in combination with organic lubricants. Based on this knowledge, it is now possible to formulate design rules for supra lubricating layer-lubricant combinations. The results are presented in an article in Nature Communications, volume 10.

One of the most important prerequisites for sustainable and environmentally friendly mobility is minimizing friction. Research and industry have been dedicated...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Our digital society in 2040

16.01.2019 | Event News

11th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Aachen, 3-4 April 2019

14.01.2019 | Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

 
Latest News

Additive manufacturing reflects fundamental metallurgical principles to create materials

18.01.2019 | Materials Sciences

How molecules teeter in a laser field

18.01.2019 | Life Sciences

The cytoskeleton of neurons has been found to be involved in Alzheimer's disease

18.01.2019 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>