A new pathogen has been discovered by scientists investigating major die-offs of pigeons native to North America, according to studies led by the University of California, Davis, and the California Department of Fish and Wildlife.
Scientists were able to implicate this new parasite, along with the ancient parasite Trichomonas gallinae, in the recent deaths of thousands of Pacific Coast band-tailed pigeons. The die-offs occurred during multiple epidemics in California’s Central Coast and Sierra Nevada mountain ranges. Scientists named the new pathogen Trichomonas stableri.
Avian trichomonosis is an emerging and potentially fatal disease that creates severe lesions that can block the esophagus, ultimately preventing the bird from eating or drinking, or the trachea, leading to suffocation. The disease may date back to when dinosaurs roamed the earth, as lesions indicative of trichomonosis were found recently in T-Rex skeletons. The disease may also have contributed to the decline of the passenger pigeon, whose extinction occurred exactly 100 years ago.
Epidemics of the disease can result in the death of thousands of birds in a short amount of time. An outbreak in Carmel Valley killed an estimated 43,000 birds in 2007.
“The same parasite species that killed band-tailed pigeons during the outbreaks were also killing the birds when there weren’t outbreaks,” said lead author Yvette Girard, a postdoctoral scholar with the Wildlife Health Center in the UC Davis School of Veterinary Medicine at the time of the studies. “This indicates there may be other factors at play in the die-offs.”
“We are now investigating what triggers these die-offs, which may be caused by the congregation of infected and vulnerable birds during certain environmental conditions, or even spillover from another nearby species,” said principal investigator Christine Johnson, a professor with the UC Davis Wildlife Health Center.
Between winter 2011 and spring 2012, there were eight mortality events — defined as more than five dead birds found in the same geographic area during the same time frame. The study said trichomonosis was confirmed in 96 percent of dead, sick or dying birds examined at seven of the mortality events. This disease was also found in:
“What makes this disease more troublesome for band-tailed pigeons is their low reproductive rate — about one chick per year — and also that these events are occurring in the wintertime,” said co-author Krysta Rogers, an environmental scientist with the California Department of Fish and Wildlife. “That means almost all the birds we’re losing during events are adult birds. They’re being killed before they have the ability to reproduce in the spring.”
Mortality events in band-tailed pigeons have been reported in California at least since 1945, but have increased during the last decade, with outbreaks reported in six of the last 10 years.
“Going into the study, we expected to find a single, highly virulent species of Trichomonas in birds sampled at outbreaks,” Girard said. “Having two species killing birds at these large-scale mortality events is surprising.”
Necropsies of the birds were conducted at the California Animal Health and Food Safety Laboratory at UC Davis and the Wildlife Investigations Laboratory at the California Department of Fish and Wildlife.
Both studies were funded by the California Department of Fish and Wildlife and the U.S. Fish and Wildlife Service.
The study naming the new species of parasite is published in the journal International Journal for Parasitology: Parasites and Wildlife. The study that explains how trichomonosis is affecting the band-tailed pigeon is published in the journal Infection, Genetics and Evolution.
UC Davis is a global community of individuals united to better humanity and our natural world while seeking solutions to some of our most pressing challenges. Located near the California state capital, UC Davis has more than 34,000 students, and the full-time equivalent of 4,100 faculty and other academics and 17,400 staff. The campus has an annual research budget of over $750 million, a comprehensive health system and about two dozen specialized research centers. The university offers interdisciplinary graduate study and 99 undergraduate majors in four colleges and six professional schools.
Yvette Girard | Eurek Alert!
Upcycling of PET Bottles: New Ideas for Resource Cycles in Germany
25.06.2018 | Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF
Dry landscapes can increase disease transmission
20.06.2018 | Forschungsverbund Berlin e.V.
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
17.07.2018 | Information Technology
17.07.2018 | Materials Sciences
17.07.2018 | Power and Electrical Engineering