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!
A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde
Value from wastewater
16.08.2017 | Hochschule Landshut
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
21.08.2017 | Materials Sciences
21.08.2017 | Health and Medicine
21.08.2017 | Materials Sciences